Provided by: scons_2.3.0-2ubuntu1_all 
NAME
scons - a software construction tool
SYNOPSIS
scons [ options... ] [ name=val... ] [ targets... ]
DESCRIPTION
The scons utility builds software (or other files) by determining which component pieces must be rebuilt
and executing the necessary commands to rebuild them.
By default, scons searches for a file named SConstruct, Sconstruct, or sconstruct (in that order) in the
current directory and reads its configuration from the first file found. An alternate file name may be
specified via the -f option.
The SConstruct file can specify subsidiary configuration files using the SConscript() function. By
convention, these subsidiary files are named SConscript, although any name may be used. (Because of this
naming convention, the term "SConscript files" is sometimes used to refer generically to all scons
configuration files, regardless of actual file name.)
The configuration files specify the target files to be built, and (optionally) the rules to build those
targets. Reasonable default rules exist for building common software components (executable programs,
object files, libraries), so that for most software projects, only the target and input files need be
specified.
Before reading the SConstruct file, scons looks for a directory named site_scons in various system
directories (see below) and the directory containing the SConstruct file; for each of those dirs which
exists, site_scons is prepended to sys.path, the file site_scons/site_init.py, is evaluated if it exists,
and the directory site_scons/site_tools is prepended to the default toolpath if it exists. See the --no-
site-dir and --site-dir options for more details.
scons reads and executes the SConscript files as Python scripts, so you may use normal Python scripting
capabilities (such as flow control, data manipulation, and imported Python libraries) to handle
complicated build situations. scons, however, reads and executes all of the SConscript files before it
begins building any targets. To make this obvious, scons prints the following messages about what it is
doing:
$ scons foo.out
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
cp foo.in foo.out
scons: done building targets.
$
The status messages (everything except the line that reads "cp foo.in foo.out") may be suppressed using
the -Q option.
scons does not automatically propagate the external environment used to execute scons to the commands
used to build target files. This is so that builds will be guaranteed repeatable regardless of the
environment variables set at the time scons is invoked. This also means that if the compiler or other
commands that you want to use to build your target files are not in standard system locations, scons will
not find them unless you explicitly set the PATH to include those locations. Whenever you create an
scons construction environment, you can propagate the value of PATH from your external environment as
follows:
import os
env = Environment(ENV = {'PATH' : os.environ['PATH']})
Similarly, if the commands use external environment variables like $PATH, $HOME, $JAVA_HOME, $LANG,
$SHELL, $TERM, etc., these variables can also be explicitly propagated:
import os
env = Environment(ENV = {'PATH' : os.environ['PATH'],
'HOME' : os.environ['HOME']})
Or you may explicitly propagate the invoking user's complete external environment:
import os
env = Environment(ENV = os.environ)
This comes at the expense of making your build dependent on the user's environment being set correctly,
but it may be more convenient for many configurations.
scons can scan known input files automatically for dependency information (for example, #include
statements in C or C++ files) and will rebuild dependent files appropriately whenever any "included"
input file changes. scons supports the ability to define new scanners for unknown input file types.
scons knows how to fetch files automatically from SCCS or RCS subdirectories using SCCS, RCS or
BitKeeper.
scons is normally executed in a top-level directory containing a SConstruct file, optionally specifying
as command-line arguments the target file or files to be built.
By default, the command
scons
will build all target files in or below the current directory. Explicit default targets (to be built
when no targets are specified on the command line) may be defined the SConscript file(s) using the
Default() function, described below.
Even when Default() targets are specified in the SConscript file(s), all target files in or below the
current directory may be built by explicitly specifying the current directory (.) as a command-line
target:
scons .
Building all target files, including any files outside of the current directory, may be specified by
supplying a command-line target of the root directory (on POSIX systems):
scons /
or the path name(s) of the volume(s) in which all the targets should be built (on Windows systems):
scons C:\ D:\
To build only specific targets, supply them as command-line arguments:
scons foo bar
in which case only the specified targets will be built (along with any derived files on which they
depend).
Specifying "cleanup" targets in SConscript files is not usually necessary. The -c flag removes all files
necessary to build the specified target:
scons -c .
to remove all target files, or:
scons -c build export
to remove target files under build and export. Additional files or directories to remove can be
specified using the Clean() function. Conversely, targets that would normally be removed by the -c
invocation can be prevented from being removed by using the NoClean() function.
A subset of a hierarchical tree may be built by remaining at the top-level directory (where the
SConstruct file lives) and specifying the subdirectory as the target to be built:
scons src/subdir
or by changing directory and invoking scons with the -u option, which traverses up the directory
hierarchy until it finds the SConstruct file, and then builds targets relatively to the current
subdirectory:
cd src/subdir
scons -u .
scons supports building multiple targets in parallel via a -j option that takes, as its argument, the
number of simultaneous tasks that may be spawned:
scons -j 4
builds four targets in parallel, for example.
scons can maintain a cache of target (derived) files that can be shared between multiple builds. When
caching is enabled in a SConscript file, any target files built by scons will be copied to the cache. If
an up-to-date target file is found in the cache, it will be retrieved from the cache instead of being
rebuilt locally. Caching behavior may be disabled and controlled in other ways by the --cache-force,
--cache-disable, and --cache-show command-line options. The --random option is useful to prevent
multiple builds from trying to update the cache simultaneously.
Values of variables to be passed to the SConscript file(s) may be specified on the command line:
scons debug=1 .
These variables are available in SConscript files through the ARGUMENTS dictionary, and can be used in
the SConscript file(s) to modify the build in any way:
if ARGUMENTS.get('debug', 0):
env = Environment(CCFLAGS = '-g')
else:
env = Environment()
The command-line variable arguments are also available in the ARGLIST list, indexed by their order on the
command line. This allows you to process them in order rather than by name, if necessary. ARGLIST[0]
returns a tuple containing (argname, argvalue). A Python exception is thrown if you try to access a list
member that does not exist.
scons requires Python version 2.4 or later. There should be no other dependencies or requirements to run
scons.
By default, scons knows how to search for available programming tools on various systems. On Windows
systems, scons searches in order for the Microsoft Visual C++ tools, the MinGW tool chain, the Intel
compiler tools, and the PharLap ETS compiler. On OS/2 systems, scons searches in order for the OS/2
compiler, the GCC tool chain, and the Microsoft Visual C++ tools, On SGI IRIX, IBM AIX, Hewlett Packard
HP-UX, and Sun Solaris systems, scons searches for the native compiler tools (MIPSpro, Visual Age, aCC,
and Forte tools respectively) and the GCC tool chain. On all other platforms, including POSIX (Linux and
UNIX) platforms, scons searches in order for the GCC tool chain, the Microsoft Visual C++ tools, and the
Intel compiler tools. You may, of course, override these default values by appropriate configuration of
Environment construction variables.
OPTIONS
In general, scons supports the same command-line options as GNU make, and many of those supported by
cons.
-b Ignored for compatibility with non-GNU versions of make.
-c, --clean, --remove
Clean up by removing all target files for which a construction command is specified. Also remove
any files or directories associated to the construction command using the Clean() function. Will
not remove any targets specified by the NoClean() function.
--cache-debug=file
Print debug information about the CacheDir() derived-file caching to the specified file. If file
is - (a hyphen), the debug information are printed to the standard output. The printed messages
describe what signature file names are being looked for in, retrieved from, or written to the
CacheDir() directory tree.
--cache-disable, --no-cache
Disable the derived-file caching specified by CacheDir(). scons will neither retrieve files from
the cache nor copy files to the cache.
--cache-force, --cache-populate
When using CacheDir(), populate a cache by copying any already-existing, up-to-date derived files
to the cache, in addition to files built by this invocation. This is useful to populate a new
cache with all the current derived files, or to add to the cache any derived files recently built
with caching disabled via the --cache-disable option.
--cache-show
When using CacheDir() and retrieving a derived file from the cache, show the command that would
have been executed to build the file, instead of the usual report, "Retrieved `file' from cache."
This will produce consistent output for build logs, regardless of whether a target file was
rebuilt or retrieved from the cache.
--config=mode
This specifies how the Configure call should use or generate the results of configuration tests.
The option should be specified from among the following choices:
--config=auto
scons will use its normal dependency mechanisms to decide if a test must be rebuilt or not. This
saves time by not running the same configuration tests every time you invoke scons, but will
overlook changes in system header files or external commands (such as compilers) if you don't
specify those dependecies explicitly. This is the default behavior.
--config=force
If this option is specified, all configuration tests will be re-run regardless of whether the
cached results are out of date. This can be used to explicitly force the configuration tests to
be updated in response to an otherwise unconfigured change in a system header file or compiler.
--config=cache
If this option is specified, no configuration tests will be rerun and all results will be taken
from cache. Note that scons will still consider it an error if --config=cache is specified and a
necessary test does not yet have any results in the cache.
-C directory, --directory=directory
Change to the specified directory before searching for the SConstruct, Sconstruct, or sconstruct
file, or doing anything else. Multiple -C options are interpreted relative to the previous one,
and the right-most -C option wins. (This option is nearly equivalent to -f directory/SConstruct,
except that it will search for SConstruct, Sconstruct, or sconstruct in the specified directory.)
-D Works exactly the same way as the -u option except for the way default targets are handled. When
this option is used and no targets are specified on the command line, all default targets are
built, whether or not they are below the current directory.
--debug=type
Debug the build process. type specifies what type of debugging:
--debug=count
Print how many objects are created of the various classes used internally by SCons before and
after reading the SConscript files and before and after building targets. This is not supported
when SCons is executed with the Python -O (optimized) option or when the SCons modules have been
compiled with optimization (that is, when executing from *.pyo files).
--debug=duplicate
Print a line for each unlink/relink (or copy) of a variant file from its source file. Includes
debugging info for unlinking stale variant files, as well as unlinking old targets before building
them.
--debug=dtree
A synonym for the newer --tree=derived option. This will be deprecated in some future release and
ultimately removed.
--debug=explain
Print an explanation of precisely why scons is deciding to (re-)build any targets. (Note: this
does not print anything for targets that are not rebuilt.)
--debug=findlibs
Instruct the scanner that searches for libraries to print a message about each potential library
name it is searching for, and about the actual libraries it finds.
--debug=includes
Print the include tree after each top-level target is built. This is generally used to find out
what files are included by the sources of a given derived file:
$ scons --debug=includes foo.o
--debug=memoizer
Prints a summary of hits and misses using the Memoizer, an internal subsystem that counts how
often SCons uses cached values in memory instead of recomputing them each time they're needed.
--debug=memory
Prints how much memory SCons uses before and after reading the SConscript files and before and
after building targets.
--debug=nomemoizer
A deprecated option preserved for backwards compatibility.
--debug=objects
Prints a list of the various objects of the various classes used internally by SCons.
--debug=pdb
Re-run SCons under the control of the pdb Python debugger.
--debug=prepare
Print a line each time any target (internal or external) is prepared for building. scons prints
this for each target it considers, even if that target is up to date (see also --debug=explain).
This can help debug problems with targets that aren't being built; it shows whether scons is at
least considering them or not.
--debug=presub
Print the raw command line used to build each target before the construction environment variables
are substituted. Also shows which targets are being built by this command. Output looks
something like this:
$ scons --debug=presub
Building myprog.o with action(s):
$SHCC $SHCFLAGS $SHCCFLAGS $CPPFLAGS $_CPPINCFLAGS -c -o $TARGET $SOURCES
...
--debug=stacktrace
Prints an internal Python stack trace when encountering an otherwise unexplained error.
--debug=stree
A synonym for the newer --tree=all,status option. This will be deprecated in some future release
and ultimately removed.
--debug=time
Prints various time profiling information: the time spent executing each individual build command;
the total build time (time SCons ran from beginning to end); the total time spent reading and
executing SConscript files; the total time spent SCons itself spend running (that is, not counting
reading and executing SConscript files); and both the total time spent executing all build
commands and the elapsed wall-clock time spent executing those build commands. (When scons is
executed without the -j option, the elapsed wall-clock time will typically be slightly longer than
the total time spent executing all the build commands, due to the SCons processing that takes
place in between executing each command. When scons is executed with the -j option, and your
build configuration allows good parallelization, the elapsed wall-clock time should be
significantly smaller than the total time spent executing all the build commands, since multiple
build commands and intervening SCons processing should take place in parallel.)
--debug=tree
A synonym for the newer --tree=all option. This will be deprecated in some future release and
ultimately removed.
--diskcheck=types
Enable specific checks for whether or not there is a file on disk where the SCons configuration
expects a directory (or vice versa), and whether or not RCS or SCCS sources exist when searching
for source and include files. The types argument can be set to: all, to enable all checks
explicitly (the default behavior); none, to disable all such checks; match, to check that files
and directories on disk match SCons' expected configuration; rcs, to check for the existence of an
RCS source for any missing source or include files; sccs, to check for the existence of an SCCS
source for any missing source or include files. Multiple checks can be specified separated by
commas; for example, --diskcheck=sccs,rcs would still check for SCCS and RCS sources, but disable
the check for on-disk matches of files and directories. Disabling some or all of these checks can
provide a performance boost for large configurations, or when the configuration will check for
files and/or directories across networked or shared file systems, at the slight increased risk of
an incorrect build or of not handling errors gracefully (if include files really should be found
in SCCS or RCS, for example, or if a file really does exist where the SCons configuration expects
a directory).
--duplicate=ORDER
There are three ways to duplicate files in a build tree: hard links, soft (symbolic) links and
copies. The default behaviour of SCons is to prefer hard links to soft links to copies. You can
specify different behaviours with this option. ORDER must be one of hard-soft-copy (the default),
soft-hard-copy, hard-copy, soft-copy or copy. SCons will attempt to duplicate files using the
mechanisms in the specified order.
-f file, --file=file, --makefile=file, --sconstruct=file
Use file as the initial SConscript file. Multiple -f options may be specified, in which case
scons will read all of the specified files.
-h, --help
Print a local help message for this build, if one is defined in the SConscript file(s), plus a
line that describes the -H option for command-line option help. If no local help message is
defined, prints the standard help message about command-line options. Exits after displaying the
appropriate message.
-H, --help-options
Print the standard help message about command-line options and exit.
-i, --ignore-errors
Ignore all errors from commands executed to rebuild files.
-I directory, --include-dir=directory
Specifies a directory to search for imported Python modules. If several -I options are used, the
directories are searched in the order specified.
--implicit-cache
Cache implicit dependencies. This causes scons to use the implicit (scanned) dependencies from
the last time it was run instead of scanning the files for implicit dependencies. This can
significantly speed up SCons, but with the following limitations:
scons will not detect changes to implicit dependency search paths (e.g. CPPPATH, LIBPATH) that
would ordinarily cause different versions of same-named files to be used.
scons will miss changes in the implicit dependencies in cases where a new implicit dependency is
added earlier in the implicit dependency search path (e.g. CPPPATH, LIBPATH) than a current
implicit dependency with the same name.
--implicit-deps-changed
Forces SCons to ignore the cached implicit dependencies. This causes the implicit dependencies to
be rescanned and recached. This implies --implicit-cache.
--implicit-deps-unchanged
Force SCons to ignore changes in the implicit dependencies. This causes cached implicit
dependencies to always be used. This implies --implicit-cache.
--interactive
Starts SCons in interactive mode. The SConscript files are read once and a scons>>> prompt is
printed. Targets may now be rebuilt by typing commands at interactive prompt without having to
re-read the SConscript files and re-initialize the dependency graph from scratch.
SCons interactive mode supports the following commands:
build[OPTIONS] [TARGETS] ...
Builds the specified TARGETS (and their dependencies) with the specified SCons command-
line OPTIONS. b and scons are synonyms.
The following SCons command-line options affect the build command:
--cache-debug=FILE
--cache-disable, --no-cache
--cache-force, --cache-populate
--cache-show
--debug=TYPE
-i, --ignore-errors
-j N, --jobs=N
-k, --keep-going
-n, --no-exec, --just-print, --dry-run, --recon
-Q
-s, --silent, --quiet
--taskmastertrace=FILE
--tree=OPTIONS
Any other SCons command-line options that are specified do not cause errors but have no
effect on the build command (mainly because they affect how the SConscript files are
read, which only happens once at the beginning of interactive mode).
clean[OPTIONS] [TARGETS] ...
Cleans the specified TARGETS (and their dependencies) with the specified options. c is a
synonym. This command is itself a synonym for build --clean
exit Exits SCons interactive mode. You can also exit by terminating input (CTRL+D on UNIX or
Linux systems, CTRL+Z on Windows systems).
help[COMMAND]
Provides a help message about the commands available in SCons interactive mode. If
COMMAND is specified, h and ? are synonyms.
shell[COMMANDLINE]
Executes the specified COMMANDLINE in a subshell. If no COMMANDLINE is specified,
executes the interactive command interpreter specified in the SHELL environment variable
(on UNIX and Linux systems) or the COMSPEC environment variable (on Windows systems). sh
and ! are synonyms.
version
Prints SCons version information.
An empty line repeats the last typed command. Command-line editing can be used if the readline
module is available.
$ scons --interactive
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons>>> build -n prog
scons>>> exit
-j N, --jobs=N
Specifies the number of jobs (commands) to run simultaneously. If there is more than one -j
option, the last one is effective.
-k, --keep-going
Continue as much as possible after an error. The target that failed and those that depend on it
will not be remade, but other targets specified on the command line will still be processed.
-m Ignored for compatibility with non-GNU versions of make.
--max-drift=SECONDS
Set the maximum expected drift in the modification time of files to SECONDS. This value
determines how long a file must be unmodified before its cached content signature will be used
instead of calculating a new content signature (MD5 checksum) of the file's contents. The default
value is 2 days, which means a file must have a modification time of at least two days ago in
order to have its cached content signature used. A negative value means to never cache the
content signature and to ignore the cached value if there already is one. A value of 0 means to
always use the cached signature, no matter how old the file is.
--md5-chunksize=KILOBYTES
Set the block size used to compute MD5 signatures to KILOBYTES. This value determines the size of
the chunks which are read in at once when computing MD5 signatures. Files below that size are
fully stored in memory before performing the signature computation while bigger files are read in
block-by-block. A huge block-size leads to high memory consumption while a very small block-size
slows down the build considerably.
The default value is to use a chunk size of 64 kilobytes, which should be appropriate for most
uses.
-n, --just-print, --dry-run, --recon
No execute. Print the commands that would be executed to build any out-of-date target files, but
do not execute the commands.
--no-site-dir
Prevents the automatic addition of the standard site_scons dirs to sys.path. Also prevents
loading the site_scons/site_init.py modules if they exist, and prevents adding their
site_scons/site_tools dirs to the toolpath.
--profile=file
Run SCons under the Python profiler and save the results in the specified file. The results may
be analyzed using the Python pstats module.
-q, --question
Do not run any commands, or print anything. Just return an exit status that is zero if the
specified targets are already up to date, non-zero otherwise.
-Q Quiets SCons status messages about reading SConscript files, building targets and entering
directories. Commands that are executed to rebuild target files are still printed.
--random
Build dependencies in a random order. This is useful when building multiple trees simultaneously
with caching enabled, to prevent multiple builds from simultaneously trying to build or retrieve
the same target files.
-s, --silent, --quiet
Silent. Do not print commands that are executed to rebuild target files. Also suppresses SCons
status messages.
-S, --no-keep-going, --stop
Ignored for compatibility with GNU make.
--site-dir=dir
Uses the named dir as the site dir rather than the default site_scons dirs. This dir will get
prepended to sys.path, the module dir/site_init.py will get loaded if it exists, and
dir/site_tools will get added to the default toolpath.
The default set of site_scons dirs used when --site-dir is not specified depends on the system
platform, as follows. Note that the directories are examined in the order given, from most
generic to most specific, so the last-executed site_init.py file is the most specific one (which
gives it the chance to override everything else), and the dirs are prepended to the paths, again
so the last dir examined comes first in the resulting path.
Windows:
%ALLUSERSPROFILE/Application Data/scons/site_scons
%USERPROFILE%/Local Settings/Application Data/scons/site_scons
%APPDATA%/scons/site_scons
%HOME%/.scons/site_scons
./site_scons
Mac OS X:
/Library/Application Support/SCons/site_scons
/opt/local/share/scons/site_scons (for MacPorts)
/sw/share/scons/site_scons (for Fink)
$HOME/Library/Application Support/SCons/site_scons
$HOME/.scons/site_scons
./site_scons
Solaris:
/opt/sfw/scons/site_scons
/usr/share/scons/site_scons
$HOME/.scons/site_scons
./site_scons
Linux, HPUX, and other Posix-like systems:
/usr/share/scons/site_scons
$HOME/.scons/site_scons
./site_scons
--stack-size=KILOBYTES
Set the size stack used to run threads to KILOBYTES. This value determines the stack size of the
threads used to run jobs. These are the threads that execute the actions of the builders for the
nodes that are out-of-date. Note that this option has no effect unless the num_jobs option, which
corresponds to -j and --jobs, is larger than one. Using a stack size that is too small may cause
stack overflow errors. This usually shows up as segmentation faults that cause scons to abort
before building anything. Using a stack size that is too large will cause scons to use more
memory than required and may slow down the entire build process.
The default value is to use a stack size of 256 kilobytes, which should be appropriate for most
uses. You should not need to increase this value unless you encounter stack overflow errors.
-t, --touch
Ignored for compatibility with GNU make. (Touching a file to make it appear up-to-date is
unnecessary when using scons.)
--taskmastertrace=file
Prints trace information to the specified file about how the internal Taskmaster object evaluates
and controls the order in which Nodes are built. A file name of - may be used to specify the
standard output.
-tree=options
Prints a tree of the dependencies after each top-level target is built. This prints out some or
all of the tree, in various formats, depending on the options specified:
--tree=all
Print the entire dependency tree after each top-level target is built. This prints out the
complete dependency tree, including implicit dependencies and ignored dependencies.
--tree=derived
Restricts the tree output to only derived (target) files, not source files.
--tree=status
Prints status information for each displayed node.
--tree=prune
Prunes the tree to avoid repeating dependency information for nodes that have already been
displayed. Any node that has already been displayed will have its name printed in [square
brackets], as an indication that the dependencies for that node can be found by searching for the
relevant output higher up in the tree.
Multiple options may be specified, separated by commas:
# Prints only derived files, with status information:
scons --tree=derived,status
# Prints all dependencies of target, with status information
# and pruning dependencies of already-visited Nodes:
scons --tree=all,prune,status target
-u, --up, --search-up
Walks up the directory structure until an SConstruct , Sconstruct or sconstruct file is found, and
uses that as the top of the directory tree. If no targets are specified on the command line, only
targets at or below the current directory will be built.
-U Works exactly the same way as the -u option except for the way default targets are handled. When
this option is used and no targets are specified on the command line, all default targets that are
defined in the SConscript(s) in the current directory are built, regardless of what directory the
resultant targets end up in.
-v, --version
Print the scons version, copyright information, list of authors, and any other relevant
information. Then exit.
-w, --print-directory
Print a message containing the working directory before and after other processing.
--no-print-directory
Turn off -w, even if it was turned on implicitly.
--warn=type, --warn=no-type
Enable or disable warnings. type specifies the type of warnings to be enabled or disabled:
--warn=all, --warn=no-all
Enables or disables all warnings.
--warn=cache-write-error, --warn=no-cache-write-error
Enables or disables warnings about errors trying to write a copy of a built file to a specified
CacheDir(). These warnings are disabled by default.
--warn=corrupt-sconsign, --warn=no-corrupt-sconsign
Enables or disables warnings about unfamiliar signature data in .sconsign files. These warnings
are enabled by default.
--warn=dependency, --warn=no-dependency
Enables or disables warnings about dependencies. These warnings are disabled by default.
--warn=deprecated, --warn=no-deprecated
Enables or disables all warnings about use of currently deprecated features. These warnings are
enabled by default. Note that the --warn=no-deprecated option does not disable warnings about
absolutely all deprecated features. Warnings for some deprecated features that have already been
through several releases with deprecation warnings may be mandatory for a release or two before
they are officially no longer supported by SCons. Warnings for some specific deprecated features
may be enabled or disabled individually; see below.
--warn=deprecated-copy, --warn=no-deprecated-copy
Enables or disables warnings about use of the deprecated env.Copy() method.
--warn=deprecated-source-signatures, --warn=no-deprecated-source-signatures
Enables or disables warnings about use of the deprecated SourceSignatures() function or
env.SourceSignatures() method.
--warn=deprecated-target-signatures, --warn=no-deprecated-target-signatures
Enables or disables warnings about use of the deprecated TargetSignatures() function or
env.TargetSignatures() method.
--warn=duplicate-environment, --warn=no-duplicate-environment
Enables or disables warnings about attempts to specify a build of a target with two different
construction environments that use the same action. These warnings are enabled by default.
--warn=fortran-cxx-mix, --warn=no-fortran-cxx-mix
Enables or disables the specific warning about linking Fortran and C++ object files in a single
executable, which can yield unpredictable behavior with some compilers.
--warn=future-deprecated, --warn=no-future-deprecated
Enables or disables warnings about features that will be deprecated in the future. These warnings
are disabled by default. Enabling this warning is especially recommended for projects that
redistribute SCons configurations for other users to build, so that the project can be warned as
soon as possible about to-be-deprecated features that may require changes to the configuration.
--warn=link, --warn=no-link
Enables or disables warnings about link steps.
--warn=misleading-keywords, --warn=no-misleading-keywords
Enables or disables warnings about use of the misspelled keywords targets and sources when calling
Builders. (Note the last s characters, the correct spellings are target and source.) These
warnings are enabled by default.
--warn=missing-sconscript, --warn=no-missing-sconscript
Enables or disables warnings about missing SConscript files. These warnings are enabled by
default.
--warn=no-md5-module, --warn=no-no-md5-module
Enables or disables warnings about the version of Python not having an MD5 checksum module
available. These warnings are enabled by default.
--warn=no-metaclass-support, --warn=no-no-metaclass-support
Enables or disables warnings about the version of Python not supporting metaclasses when the
--debug=memoizer option is used. These warnings are enabled by default.
--warn=no-object-count, --warn=no-no-object-count
Enables or disables warnings about the --debug=object feature not working when scons is run with
the python -O option or from optimized Python (.pyo) modules.
--warn=no-parallel-support, --warn=no-no-parallel-support
Enables or disables warnings about the version of Python not being able to support parallel builds
when the -j option is used. These warnings are enabled by default.
--warn=python-version, --warn=no-python-version
Enables or disables the warning about running SCons with a deprecated version of Python. These
warnings are enabled by default.
--warn=reserved-variable, --warn=no-reserved-variable
Enables or disables warnings about attempts to set the reserved construction variable names
CHANGED_SOURCES, CHANGED_TARGETS, TARGET, TARGETS, SOURCE, SOURCES, UNCHANGED_SOURCES or
UNCHANGED_TARGETS. These warnings are disabled by default.
--warn=stack-size, --warn=no-stack-size
Enables or disables warnings about requests to set the stack size that could not be honored.
These warnings are enabled by default.
-Y repository, --repository=repository, --srcdir=repository
Search the specified repository for any input and target files not found in the local directory
hierarchy. Multiple -Y options may be specified, in which case the repositories are searched in
the order specified.
CONFIGURATION FILE REFERENCE
Construction Environments
A construction environment is the basic means by which the SConscript files communicate build information
to scons. A new construction environment is created using the Environment function:
env = Environment()
Variables, called construction variables, may be set in a construction environment either by specifying
them as keywords when the object is created or by assigning them a value after the object is created:
env = Environment(FOO = 'foo')
env['BAR'] = 'bar'
As a convenience, construction variables may also be set or modified by the parse_flags keyword argument,
which applies the ParseFlags method (described below) to the argument value after all other processing is
completed. This is useful either if the exact content of the flags is unknown (for example, read from a
control file) or if the flags are distributed to a number of construction variables.
env = Environment(parse_flags = '-Iinclude -DEBUG -lm')
This example adds 'include' to CPPPATH, 'EBUG' to CPPDEFINES, and 'm' to LIBS.
By default, a new construction environment is initialized with a set of builder methods and construction
variables that are appropriate for the current platform. An optional platform keyword argument may be
used to specify that an environment should be initialized for a different platform:
env = Environment(platform = 'cygwin')
env = Environment(platform = 'os2')
env = Environment(platform = 'posix')
env = Environment(platform = 'win32')
Specifying a platform initializes the appropriate construction variables in the environment to use and
generate file names with prefixes and suffixes appropriate for the platform.
Note that the win32 platform adds the SystemDrive and SystemRoot variables from the user's external
environment to the construction environment's ENV dictionary. This is so that any executed commands that
use sockets to connect with other systems (such as fetching source files from external CVS repository
specifications like :pserver:anonymous@cvs.sourceforge.net:/cvsroot/scons) will work on Windows systems.
The platform argument may be function or callable object, in which case the Environment() method will
call the specified argument to update the new construction environment:
def my_platform(env):
env['VAR'] = 'xyzzy'
env = Environment(platform = my_platform)
Additionally, a specific set of tools with which to initialize the environment may be specified as an
optional keyword argument:
env = Environment(tools = ['msvc', 'lex'])
Non-built-in tools may be specified using the toolpath argument:
env = Environment(tools = ['default', 'foo'], toolpath = ['tools'])
This looks for a tool specification in tools/foo.py (as well as using the ordinary default tools for the
platform). foo.py should have two functions: generate(env, **kw) and exists(env). The generate()
function modifies the passed-in environment to set up variables so that the tool can be executed; it may
use any keyword arguments that the user supplies (see below) to vary its initialization. The exists()
function should return a true value if the tool is available. Tools in the toolpath are used before any
of the built-in ones. For example, adding gcc.py to the toolpath would override the built-in gcc tool.
Also note that the toolpath is stored in the environment for use by later calls to Clone() and Tool()
methods:
base = Environment(toolpath=['custom_path'])
derived = base.Clone(tools=['custom_tool'])
derived.CustomBuilder()
The elements of the tools list may also be functions or callable objects, in which case the Environment()
method will call the specified elements to update the new construction environment:
def my_tool(env):
env['XYZZY'] = 'xyzzy'
env = Environment(tools = [my_tool])
The individual elements of the tools list may also themselves be two-element lists of the form (toolname,
kw_dict). SCons searches for the toolname specification file as described above, and passes kw_dict,
which must be a dictionary, as keyword arguments to the tool's generate function. The generate function
can use the arguments to modify the tool's behavior by setting up the environment in different ways or
otherwise changing its initialization.
# in tools/my_tool.py:
def generate(env, **kw):
# Sets MY_TOOL to the value of keyword argument 'arg1' or 1.
env['MY_TOOL'] = kw.get('arg1', '1')
def exists(env):
return 1
# in SConstruct:
env = Environment(tools = ['default', ('my_tool', {'arg1': 'abc'})],
toolpath=['tools'])
The tool definition (i.e. my_tool()) can use the PLATFORM variable from the environment it receives to
customize the tool for different platforms.
If no tool list is specified, then SCons will auto-detect the installed tools using the PATH variable in
the ENV construction variable and the platform name when the Environment is constructed. Changing the
PATH variable after the Environment is constructed will not cause the tools to be redetected.
SCons supports the following tool specifications out of the box:
386asm
aixc++
aixcc
aixf77
aixlink
ar
as
bcc32
c++
cc
cvf
dmd
dvipdf
dvips
f77
f90
f95
fortran
g++
g77
gas
gcc
gfortran
gnulink
gs
hpc++
hpcc
hplink
icc
icl
ifl
ifort
ilink
ilink32
intelc
jar
javac
javah
latex
lex
link
linkloc
m4
masm
midl
mingw
mslib
mslink
mssdk
msvc
msvs
mwcc
mwld
nasm
pdflatex
pdftex
qt
rmic
rpcgen
sgiar
sgic++
sgicc
sgilink
sunar
sunc++
suncc
sunf77
sunf90
sunf95
sunlink
swig
tar
tex
textfile
tlib
yacc
zip
Additionally, there is a "tool" named default which configures the environment with a default set of
tools for the current platform.
On posix and cygwin platforms the GNU tools (e.g. gcc) are preferred by SCons, on Windows the Microsoft
tools (e.g. msvc) followed by MinGW are preferred by SCons, and in OS/2 the IBM tools (e.g. icc) are
preferred by SCons.
Builder Methods
Build rules are specified by calling a construction environment's builder methods. The arguments to the
builder methods are target (a list of targets to be built, usually file names) and source (a list of
sources to be built, usually file names).
Because long lists of file names can lead to a lot of quoting, scons supplies a Split() global function
and a same-named environment method that split a single string into a list, separated on strings of
white-space characters. (These are similar to the split() member function of Python strings but work
even if the input isn't a string.)
Like all Python arguments, the target and source arguments to a builder method can be specified either
with or without the "target" and "source" keywords. When the keywords are omitted, the target is first,
followed by the source. The following are equivalent examples of calling the Program builder method:
env.Program('bar', ['bar.c', 'foo.c'])
env.Program('bar', Split('bar.c foo.c'))
env.Program('bar', env.Split('bar.c foo.c'))
env.Program(source = ['bar.c', 'foo.c'], target = 'bar')
env.Program(target = 'bar', Split('bar.c foo.c'))
env.Program(target = 'bar', env.Split('bar.c foo.c'))
env.Program('bar', source = 'bar.c foo.c'.split())
Target and source file names that are not absolute path names (that is, do not begin with / on POSIX
systems or on Windows systems, with or without an optional drive letter) are interpreted relative to the
directory containing the SConscript file being read. An initial # (hash mark) on a path name means that
the rest of the file name is interpreted relative to the directory containing the top-level SConstruct
file, even if the # is followed by a directory separator character (slash or backslash).
Examples:
# The comments describing the targets that will be built
# assume these calls are in a SConscript file in the
# a subdirectory named "subdir".
# Builds the program "subdir/foo" from "subdir/foo.c":
env.Program('foo', 'foo.c')
# Builds the program "/tmp/bar" from "subdir/bar.c":
env.Program('/tmp/bar', 'bar.c')
# An initial '#' or '#/' are equivalent; the following
# calls build the programs "foo" and "bar" (in the
# top-level SConstruct directory) from "subdir/foo.c" and
# "subdir/bar.c", respectively:
env.Program('#foo', 'foo.c')
env.Program('#/bar', 'bar.c')
# Builds the program "other/foo" (relative to the top-level
# SConstruct directory) from "subdir/foo.c":
env.Program('#other/foo', 'foo.c')
When the target shares the same base name as the source and only the suffix varies, and if the builder
method has a suffix defined for the target file type, then the target argument may be omitted completely,
and scons will deduce the target file name from the source file name. The following examples all build
the executable program bar (on POSIX systems) or bar.exe (on Windows systems) from the bar.c source file:
env.Program(target = 'bar', source = 'bar.c')
env.Program('bar', source = 'bar.c')
env.Program(source = 'bar.c')
env.Program('bar.c')
As a convenience, a srcdir keyword argument may be specified when calling a Builder. When specified, all
source file strings that are not absolute paths will be interpreted relative to the specified srcdir.
The following example will build the build/prog (or build/prog.exe on Windows) program from the files
src/f1.c and src/f2.c:
env.Program('build/prog', ['f1.c', 'f2.c'], srcdir='src')
It is possible to override or add construction variables when calling a builder method by passing
additional keyword arguments. These overridden or added variables will only be in effect when building
the target, so they will not affect other parts of the build. For example, if you want to add additional
libraries for just one program:
env.Program('hello', 'hello.c', LIBS=['gl', 'glut'])
or generate a shared library with a non-standard suffix:
env.SharedLibrary('word', 'word.cpp',
SHLIBSUFFIX='.ocx',
LIBSUFFIXES=['.ocx'])
(Note that both the $SHLIBSUFFIX and $LIBSUFFIXES variables must be set if you want SCons to search
automatically for dependencies on the non-standard library names; see the descriptions of these
variables, below, for more information.)
It is also possible to use the parse_flags keyword argument in an override:
env = Program('hello', 'hello.c', parse_flags = '-Iinclude -DEBUG -lm')
This example adds 'include' to CPPPATH, 'EBUG' to CPPDEFINES, and 'm' to LIBS.
Although the builder methods defined by scons are, in fact, methods of a construction environment object,
they may also be called without an explicit environment:
Program('hello', 'hello.c')
SharedLibrary('word', 'word.cpp')
In this case, the methods are called internally using a default construction environment that consists of
the tools and values that scons has determined are appropriate for the local system.
Builder methods that can be called without an explicit environment may be called from custom Python
modules that you import into an SConscript file by adding the following to the Python module:
from SCons.Script import *
All builder methods return a list-like object containing Nodes that represent the target or targets that
will be built. A Node is an internal SCons object which represents build targets or sources.
The returned Node-list object can be passed to other builder methods as source(s) or passed to any SCons
function or method where a filename would normally be accepted. For example, if it were necessary to add
a specific -D flag when compiling one specific object file:
bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR')
env.Program(source = ['foo.c', bar_obj_list, 'main.c'])
Using a Node in this way makes for a more portable build by avoiding having to specify a platform-
specific object suffix when calling the Program() builder method.
Note that Builder calls will automatically "flatten" the source and target file lists, so it's all right
to have the bar_obj list return by the StaticObject() call in the middle of the source file list. If you
need to manipulate a list of lists returned by Builders directly using Python, you can either build the
list by hand:
foo = Object('foo.c')
bar = Object('bar.c')
objects = ['begin.o'] + foo + ['middle.o'] + bar + ['end.o']
for object in objects:
print str(object)
Or you can use the Flatten() function supplied by scons to create a list containing just the Nodes, which
may be more convenient:
foo = Object('foo.c')
bar = Object('bar.c')
objects = Flatten(['begin.o', foo, 'middle.o', bar, 'end.o'])
for object in objects:
print str(object)
Note also that because Builder calls return a list-like object, not an actual Python list, you should not
use the Python += operator to append Builder results to a Python list. Because the list and the object
are different types, Python will not update the original list in place, but will instead create a new
Node-list object containing the concatenation of the list elements and the Builder results. This will
cause problems for any other Python variables in your SCons configuration that still hold on to a
reference to the original list. Instead, use the Python .extend() method to make sure the list is
updated in-place. Example:
object_files = []
# Do NOT use += as follows:
#
# object_files += Object('bar.c')
#
# It will not update the object_files list in place.
#
# Instead, use the .extend() method:
object_files.extend(Object('bar.c'))
The path name for a Node's file may be used by passing the Node to the Python-builtin str() function:
bar_obj_list = env.StaticObject('bar.c', CPPDEFINES='-DBAR')
print "The path to bar_obj is:", str(bar_obj_list[0])
Note again that because the Builder call returns a list, we have to access the first element in the list
(bar_obj_list[0]) to get at the Node that actually represents the object file.
Builder calls support a chdir keyword argument that specifies that the Builder's action(s) should be
executed after changing directory. If the chdir argument is a string or a directory Node, scons will
change to the specified directory. If the chdir is not a string or Node and is non-zero, then scons will
change to the target file's directory.
# scons will change to the "sub" subdirectory
# before executing the "cp" command.
env.Command('sub/dir/foo.out', 'sub/dir/foo.in',
"cp dir/foo.in dir/foo.out",
chdir='sub')
# Because chdir is not a string, scons will change to the
# target's directory ("sub/dir") before executing the
# "cp" command.
env.Command('sub/dir/foo.out', 'sub/dir/foo.in',
"cp foo.in foo.out",
chdir=1)
Note that scons will not automatically modify its expansion of construction variables like $TARGET and
$SOURCE when using the chdir keyword argument--that is, the expanded file names will still be relative to
the top-level SConstruct directory, and consequently incorrect relative to the chdir directory. If you
use the chdir keyword argument, you will typically need to supply a different command line using
expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets and
source.
scons provides the following builder methods:
CFile()
env.CFile()
Builds a C source file given a lex (.l) or yacc (.y) input file. The suffix specified by the
$CFILESUFFIX construction variable (.c by default) is automatically added to the target if it is
not already present. Example:
# builds foo.c
env.CFile(target = 'foo.c', source = 'foo.l')
# builds bar.c
env.CFile(target = 'bar', source = 'bar.y')
Command()
env.Command()
The Command() "Builder" is actually implemented as a function that looks like a Builder, but
actually takes an additional argument of the action from which the Builder should be made. See
the Command() function description for the calling syntax and details.
CXXFile()
env.CXXFile()
Builds a C++ source file given a lex (.ll) or yacc (.yy) input file. The suffix specified by the
$CXXFILESUFFIX construction variable (.cc by default) is automatically added to the target if it
is not already present. Example:
# builds foo.cc
env.CXXFile(target = 'foo.cc', source = 'foo.ll')
# builds bar.cc
env.CXXFile(target = 'bar', source = 'bar.yy')
DVI()
env.DVI()
Builds a .dvi file from a .tex, .ltx or .latex input file. If the source file suffix is .tex,
scons will examine the contents of the file; if the string ocumentclass or ocumentstyle is found,
the file is assumed to be a LaTeX file and the target is built by invoking the $LATEXCOM command
line; otherwise, the $TEXCOM command line is used. If the file is a LaTeX file, the DVI() builder
method will also examine the contents of the .aux file and invoke the $BIBTEX command line if the
string bibdata is found, start $MAKEINDEX to generate an index if a .ind file is found and will
examine the contents .log file and re-run the $LATEXCOM command if the log file says it is
necessary.
The suffix .dvi (hard-coded within TeX itself) is automatically added to the target if it is not
already present. Examples:
# builds from aaa.tex
env.DVI(target = 'aaa.dvi', source = 'aaa.tex')
# builds bbb.dvi
env.DVI(target = 'bbb', source = 'bbb.ltx')
# builds from ccc.latex
env.DVI(target = 'ccc.dvi', source = 'ccc.latex')
Install()
env.Install()
Installs one or more source files or directories in the specified target, which must be a
directory. The names of the specified source files or directories remain the same within the
destination directory. The sources may be given as a string or as a node returned by a builder.
env.Install('/usr/local/bin', source = ['foo', 'bar'])
InstallAs()
env.InstallAs()
Installs one or more source files or directories to specific names, allowing changing a file or
directory name as part of the installation. It is an error if the target and source arguments
list different numbers of files or directories.
InstallVersionedLib()
env.InstallVersionedLib()
Installs a versioned shared library. The $SHLIBVERSION construction variable should be defined in
the environment to confirm the version number in the library name. The symlinks appropriate to
the architecture will be generated.
env.InstallAs(target = '/usr/local/bin/foo',
source = 'foo_debug')
env.InstallAs(target = ['../lib/libfoo.a', '../lib/libbar.a'],
source = ['libFOO.a', 'libBAR.a'])
Jar()
env.Jar()
Builds a Java archive (.jar) file from the specified list of sources. Any directories in the
source list will be searched for .class files). Any .java files in the source list will be
compiled to .class files by calling the Java() Builder.
If the $JARCHDIR value is set, the jar command will change to the specified directory using the -C
option. If $JARCHDIR is not set explicitly, &SCons; will use the top of any subdirectory tree in
which Java .class were built by the Java() Builder.
If the contents any of the source files begin with the string Manifest-Version, the file is
assumed to be a manifest and is passed to the jar command with the m option set.
env.Jar(target = 'foo.jar', source = 'classes')
env.Jar(target = 'bar.jar',
source = ['bar1.java', 'bar2.java'])
Java()
env.Java()
Builds one or more Java class files. The sources may be any combination of explicit .java files,
or directory trees which will be scanned for .java files.
SCons will parse each source .java file to find the classes (including inner classes) defined
within that file, and from that figure out the target .class files that will be created. The
class files will be placed underneath the specified target directory.
SCons will also search each Java file for the Java package name, which it assumes can be found on
a line beginning with the string package in the first column; the resulting .class files will be
placed in a directory reflecting the specified package name. For example, the file Foo.java
defining a single public Foo class and containing a package name of sub.dir will generate a
corresponding sub/dir/Foo.class class file.
Examples:
env.Java(target = 'classes', source = 'src')
env.Java(target = 'classes', source = ['src1', 'src2'])
env.Java(target = 'classes', source = ['File1.java', 'File2.java'])
Java source files can use the native encoding for the underlying OS. Since SCons compiles in
simple ASCII mode by default, the compiler will generate warnings about unmappable characters,
which may lead to errors as the file is processed further. In this case, the user must specify
the LANG environment variable to tell the compiler what encoding is used. For portibility, it's
best if the encoding is hard-coded so that the compile will work if it is done on a system with a
different encoding.
env = Environment()
env['ENV']['LANG'] = 'en_GB.UTF-8'
JavaH()
env.JavaH()
Builds C header and source files for implementing Java native methods. The target can be either a
directory in which the header files will be written, or a header file name which will contain all
of the definitions. The source can be the names of .class files, the names of .java files to be
compiled into .class files by calling the Java() builder method, or the objects returned from the
Java() builder method.
If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the
JavaH() builder method itself, then the value of the variable will be stripped from the beginning
of any .class file names.
Examples:
# builds java_native.h
classes = env.Java(target = 'classdir', source = 'src')
env.JavaH(target = 'java_native.h', source = classes)
# builds include/package_foo.h and include/package_bar.h
env.JavaH(target = 'include',
source = ['package/foo.class', 'package/bar.class'])
# builds export/foo.h and export/bar.h
env.JavaH(target = 'export',
source = ['classes/foo.class', 'classes/bar.class'],
JAVACLASSDIR = 'classes')
Library()
env.Library()
A synonym for the StaticLibrary() builder method.
LoadableModule()
env.LoadableModule()
On most systems, this is the same as SharedLibrary(). On Mac OS X (Darwin) platforms, this
creates a loadable module bundle.
M4()
env.M4()
Builds an output file from an M4 input file. This uses a default $M4FLAGS value of -E, which
considers all warnings to be fatal and stops on the first warning when using the GNU version of
m4. Example:
env.M4(target = 'foo.c', source = 'foo.c.m4')
Moc()
env.Moc()
Builds an output file from a moc input file. Moc input files are either header files or cxx files.
This builder is only available after using the tool 'qt'. See the $QTDIR variable for more
information. Example:
env.Moc('foo.h') # generates moc_foo.cc
env.Moc('foo.cpp') # generates foo.moc
MOFiles()
env.MOFiles()
This builder belongs to &t-link-msgfmt; tool. The builder compiles PO files to MO files.
Example1. Create pl.mo and en.mo by compiling pl.poanden.po:
# ...
env.MOFiles(['pl', 'en'])
Example2. Compile files for languages defined in LINGUAS file:
# ...
env.MOFiles(LINGUAS_FILE = 1)
Example3. Create pl.mo and en.mo by compiling pl.po and en.po plus files for languages defined in
LINGUAS file:
# ...
env.MOFiles(['pl', 'en'], LINGUAS_FILE = 1)
Example4. Compile files for languages defined in LINGUAS file (another version):
# ...
env['LINGUAS_FILE'] = 1
env.MOFiles()
MSVSProject()
env.MSVSProject()
Builds a Microsoft Visual Studio project file, and by default builds a solution file as well.
This builds a Visual Studio project file, based on the version of Visual Studio that is configured
(either the latest installed version, or the version specified by $MSVS_VERSION in the Environment
constructor). For Visual Studio 6, it will generate a .dsp file. For Visual Studio 7 (.NET) and
later versions, it will generate a .vcproj file.
By default, this also generates a solution file for the specified project, a .dsw file for Visual
Studio 6 or a .sln file for Visual Studio 7 (.NET). This behavior may be disabled by specifying
auto_build_solution=0 when you call MSVSProject(), in which case you presumably want to build the
solution file(s) by calling the MSVSSolution() Builder (see below).
The MSVSProject() builder takes several lists of filenames to be placed into the project file.
These are currently limited to srcs, incs, localincs, resources, and misc. These are pretty self-
explanatory, but it should be noted that these lists are added to the $SOURCES construction
variable as strings, NOT as SCons File Nodes. This is because they represent file names to be
added to the project file, not the source files used to build the project file.
The above filename lists are all optional, although at least one must be specified for the
resulting project file to be non-empty.
In addition to the above lists of values, the following values may be specified:
target: The name of the target .dsp or .vcproj file. The correct suffix for the version of Visual
Studio must be used, but the $MSVSPROJECTSUFFIX construction variable will be defined to the
correct value (see example below).
variant: The name of this particular variant. For Visual Studio 7 projects, this can also be a
list of variant names. These are typically things like "Debug" or "Release", but really can be
anything you want. For Visual Studio 7 projects, they may also specify a target platform
separated from the variant name by a | (vertical pipe) character: Debug|Xbox. The default target
platform is Win32. Multiple calls to MSVSProject() with different variants are allowed; all
variants will be added to the project file with their appropriate build targets and sources.
buildtarget: An optional string, node, or list of strings or nodes (one per build variant), to
tell the Visual Studio debugger what output target to use in what build variant. The number of
buildtarget entries must match the number of variant entries.
runfile: The name of the file that Visual Studio 7 and later will run and debug. This appears as
the value of the Output field in the resutling Visual Studio project file. If this is not
specified, the default is the same as the specified buildtarget value.
Note that because &SCons; always executes its build commands from the directory in which the
SConstruct file is located, if you generate a project file in a different directory than the
SConstruct directory, users will not be able to double-click on the file name in compilation error
messages displayed in the Visual Studio console output window. This can be remedied by adding the
Visual C/C++ /FC compiler option to the $CCFLAGS variable so that the compiler will print the
full path name of any files that cause compilation errors.
Example usage:
barsrcs = ['bar.cpp'],
barincs = ['bar.h'],
barlocalincs = ['StdAfx.h']
barresources = ['bar.rc','resource.h']
barmisc = ['bar_readme.txt']
dll = env.SharedLibrary(target = 'bar.dll',
source = barsrcs)
env.MSVSProject(target = 'Bar' + env['MSVSPROJECTSUFFIX'],
srcs = barsrcs,
incs = barincs,
localincs = barlocalincs,
resources = barresources,
misc = barmisc,
buildtarget = dll,
variant = 'Release')
MSVSSolution()
env.MSVSSolution()
Builds a Microsoft Visual Studio solution file.
This builds a Visual Studio solution file, based on the version of Visual Studio that is
configured (either the latest installed version, or the version specified by $MSVS_VERSION in the
construction environment). For Visual Studio 6, it will generate a .dsw file. For Visual Studio
7 (.NET), it will generate a .sln file.
The following values must be specified:
target: The name of the target .dsw or .sln file. The correct suffix for the version of Visual
Studio must be used, but the value $MSVSSOLUTIONSUFFIX will be defined to the correct value (see
example below).
variant: The name of this particular variant, or a list of variant names (the latter is only
supported for MSVS 7 solutions). These are typically things like "Debug" or "Release", but really
can be anything you want. For MSVS 7 they may also specify target platform, like this
"Debug|Xbox". Default platform is Win32.
projects: A list of project file names, or Project nodes returned by calls to the MSVSProject()
Builder, to be placed into the solution file. It should be noted that these file names are NOT
added to the $SOURCES environment variable in form of files, but rather as strings. This is
because they represent file names to be added to the solution file, not the source files used to
build the solution file.
Example Usage:
env.MSVSSolution(target = 'Bar' + env['MSVSSOLUTIONSUFFIX'],
projects = ['bar' + env['MSVSPROJECTSUFFIX']],
variant = 'Release')
Object()
env.Object()
A synonym for the StaticObject() builder method.
Package()
env.Package()
Builds software distribution packages. Packages consist of files to install and packaging
information. The former may be specified with the source parameter and may be left out, in which
case the &FindInstalledFiles; function will collect all files that have an Install() or
InstallAs() Builder attached. If the target is not specified it will be deduced from additional
information given to this Builder.
The packaging information is specified with the help of construction variables documented below.
This information is called a tag to stress that some of them can also be attached to files with
the &Tag; function. The mandatory ones will complain if they were not specified. They vary
depending on chosen target packager.
The target packager may be selected with the "PACKAGETYPE" command line option or with the
$PACKAGETYPE construction variable. Currently the following packagers available:
* msi - Microsoft Installer
* rpm - Redhat Package Manger
* ipkg - Itsy Package Management System
* tarbz2 - compressed tar
* targz - compressed tar
* zip - zip file
* src_tarbz2 - compressed tar source
* src_targz - compressed tar source
* src_zip - zip file source
An updated list is always available under the "package_type" option when running "scons --help" on
a project that has packaging activated.
env = Environment(tools=['default', 'packaging'])
env.Install('/bin/', 'my_program')
env.Package( NAME = 'foo',
VERSION = '1.2.3',
PACKAGEVERSION = 0,
PACKAGETYPE = 'rpm',
LICENSE = 'gpl',
SUMMARY = 'balalalalal',
DESCRIPTION = 'this should be really really long',
X_RPM_GROUP = 'Application/fu',
SOURCE_URL = 'http://foo.org/foo-1.2.3.tar.gz'
)
PCH()
env.PCH()
Builds a Microsoft Visual C++ precompiled header. Calling this builder method returns a list of
two targets: the PCH as the first element, and the object file as the second element. Normally the
object file is ignored. This builder method is only provided when Microsoft Visual C++ is being
used as the compiler. The PCH builder method is generally used in conjunction with the PCH
construction variable to force object files to use the precompiled header:
env['PCH'] = env.PCH('StdAfx.cpp')[0]
PDF()
env.PDF()
Builds a .pdf file from a .dvi input file (or, by extension, a .tex, .ltx, or .latex input file).
The suffix specified by the $PDFSUFFIX construction variable (.pdf by default) is added
automatically to the target if it is not already present. Example:
# builds from aaa.tex
env.PDF(target = 'aaa.pdf', source = 'aaa.tex')
# builds bbb.pdf from bbb.dvi
env.PDF(target = 'bbb', source = 'bbb.dvi')
POInit()
env.POInit()
This builder belongs to &t-link-msginit; tool. The builder initializes missing PO file(s) if
$POAUTOINIT is set. If $POAUTOINIT is not set (default), POInit() prints instruction for user
(that is supposed to be a translator), telling how the PO file should be initialized. In normal
projects youshouldnotusePOInit()andusePOUpdate() instead. POUpdate() chooses intelligently between
msgmerge(1)andmsginit(1).POInit() always uses msginit(1) and should be regarded as builder for
special purposes or for temporary use (e.g. for quick, one time initialization of a bunch of PO
files) or for tests.
Target nodes defined through POInit() are not built by default (they're Ignored from '.' node) but
are added to special Alias ('po-create' by default). The alias name may be changed through the
$POCREATE_ALIAS construction variable. All PO files defined through
POInit()maybeeasilyinitializedbysconspo-create.
Example1. Initialize en.po and pl.po from messages.pot:
# ...
env.POInit(['en', 'pl']) # messages.pot --> [en.po, pl.po]
Example2. Initialize en.po and pl.po from foo.pot:
# ...
env.POInit(['en', 'pl'], ['foo']) # foo.pot --> [en.po, pl.po]
Example3. Initialize en.po and pl.po from foo.pot but using $POTDOMAIN construction variable:
# ...
env.POInit(['en', 'pl'], POTDOMAIN='foo') # foo.pot --> [en.po, pl.po]
Example4. Initialize PO files for languages defined in LINGUAS file. The files will be
initialized from template messages.pot:
# ...
env.POInit(LINGUAS_FILE = 1) # needs 'LINGUAS' file
Example5. Initialize en.po and pl.pl PO files plus files for languages defined in LINGUAS file.
The files will be initialized from template messages.pot:
# ...
env.POInit(['en', 'pl'], LINGUAS_FILE = 1)
Example6. You may preconfigure your environment first, and then initialize PO files:
# ...
env['POAUTOINIT'] = 1
env['LINGUAS_FILE'] = 1
env['POTDOMAIN'] = 'foo'
env.POInit()
which has same efect as:
# ...
env.POInit(POAUTOINIT = 1, LINGUAS_FILE = 1, POTDOMAIN = 'foo')
PostScript()
env.PostScript()
Builds a .ps file from a .dvi input file (or, by extension, a .tex, .ltx, or .latex input file).
The suffix specified by the $PSSUFFIX construction variable (.ps by default) is added
automatically to the target if it is not already present. Example:
# builds from aaa.tex
env.PostScript(target = 'aaa.ps', source = 'aaa.tex')
# builds bbb.ps from bbb.dvi
env.PostScript(target = 'bbb', source = 'bbb.dvi')
POTUpdate()
env.POTUpdate()
The builder belongs to &t-link-xgettext; tool. The builder updates target POT file if exists or
creates one if it doesn't. The node is not built by default (i.e. it is Ignored from '.'), but
only on demand (i.e. when given POT file is required or when special alias is invoked). This
builder adds its targe node (messages.pot, say) to a special alias (pot-update by default, see
$POTUPDATE_ALIAS) so you can update/create them easily with scons pot-update. The file is not
written until there is no real change in internationalized messages (or in comments that enter POT
file).
<note> You may see xgettext(1) being invoked by the &t-link-xgettext; tool even if there is no
real change in internationalized messages (so the POT file is not being updated). This happens
every time a source file has changed. In such case we invoke xgettext(1) and compare its output
with the content of POT file to decide whether the file should be updated or not.</para></note>
Example 1. Let's create po/ directory and place following SConstruct script there:
# SConstruct in 'po/' subdir
env = Environment( tools = ['default', 'xgettext'] )
env.POTUpdate(['foo'], ['../a.cpp', '../b.cpp'])
env.POTUpdate(['bar'], ['../c.cpp', '../d.cpp'])
Then invoke scons few times:
user@host:$ scons # Does not create foo.pot nor bar.pot
user@host:$ scons foo.pot # Updates or creates foo.pot
user@host:$ scons pot-update # Updates or creates foo.pot and bar.pot
user@host:$ scons -c # Does not clean foo.pot nor bar.pot.
the results shall be as the comments above say.
Example 2. The POTUpdate() builder may be used with no target specified, in which case default target
messages.pot will be used. The default target may also be overridden by setting $POTDOMAIN construction
variable or providing it as an override to POTUpdate() builder:
# SConstruct script
env = Environment( tools = ['default', 'xgettext'] )
env['POTDOMAIN'] = "foo"
env.POTUpdate(source = ["a.cpp", "b.cpp"]) # Creates foo.pot ...
env.POTUpdate(POTDOMAIN = "bar", source = ["c.cpp", "d.cpp"]) # and bar.pot
Example 3. The sources may be specified within separate file, for example POTFILES.in:
# POTFILES.in in 'po/' subdirectory
../a.cpp
../b.cpp
# end of file
The name of the file (POTFILES.in) containing the list of sources is provided via $XGETTEXTFROM:
# SConstruct file in 'po/' subdirectory
env = Environment( tools = ['default', 'xgettext'] )
env.POTUpdate(XGETTEXTFROM = 'POTFILES.in')
Example 4. You may use $XGETTEXTPATH to define source search path. Assume, for example, that you
have files a.cpp, b.cpp,po/SConstruct, po/POTFILES.in.ThenyourPOT-related files could look as
below:
# POTFILES.in in 'po/' subdirectory
a.cpp
b.cpp
# end of file
# SConstruct file in 'po/' subdirectory
env = Environment( tools = ['default', 'xgettext'] )
env.POTUpdate(XGETTEXTFROM = 'POTFILES.in', XGETTEXTPATH='../')
Example 5. Multiple search directories may be defined within a list, i.e. XGETTEXTPATH =
['dir1', 'dir2', ...]. The order in the list determines the search order of source files. The path
to the first file found is used.
Let's create 0/1/po/SConstruct script:
# SConstruct file in '0/1/po/' subdirectory
env = Environment( tools = ['default', 'xgettext'] )
env.POTUpdate(XGETTEXTFROM = 'POTFILES.in', XGETTEXTPATH=['../', '../../'])
and 0/1/po/POTFILES.in:
# POTFILES.in in '0/1/po/' subdirectory
a.cpp
# end of file
Write two *.cpp files, the first one is 0/a.cpp:
/* 0/a.cpp */
gettext("Hello from ../../a.cpp")
and the second is 0/1/a.cpp:
/* 0/1/a.cpp */
gettext("Hello from ../a.cpp")
then run scons. You'll obtain 0/1/po/messages.pot with the message "Hello from ../a.cpp". When you
reverse order in $XGETTEXTFOM, i.e. when you write SConscript as
# SConstruct file in '0/1/po/' subdirectory
env = Environment( tools = ['default', 'xgettext'] )
env.POTUpdate(XGETTEXTFROM = 'POTFILES.in', XGETTEXTPATH=['../../', '../'])
then the messages.pot will contain msgid "Hello from ../../a.cpp" line and not msgidHello from
../a.cpp.
POUpdate()
env.POUpdate()
The builder belongs to &t-link-msgmerge; tool. The builder updates PO files with msgmerge(1), or
initializes missing PO files as described in documentation of &t-link-msginit; tool and POInit()
builder (see also $POAUTOINIT). Note, that POUpdate() does not add its targets to po-create alias
as POInit() does.
Target nodes defined through POUpdate() are not built by default (they're Ignored from '.' node).
Instead, they are added automatically to special Alias ('po-update' by default). The alias name
may be changed through the $POUPDATE_ALIAS construction variable. You can easily update PO files
in your project by scons po-update.
Example 1. Update en.po and pl.po from messages.pottemplate(seealso$POTDOMAIN), assuming that the
later one exists or there is rule to build it (see POTUpdate()):
# ...
env.POUpdate(['en','pl']) # messages.pot --> [en.po, pl.po]
Example 2. Update en.po and pl.po from foo.pot template:
# ...
env.POUpdate(['en', 'pl'], ['foo']) # foo.pot --> [en.po, pl.pl]
Example 3. Update en.po and pl.po from foo.pot (another version):
# ...
env.POUpdate(['en', 'pl'], POTDOMAIN='foo') # foo.pot -- > [en.po, pl.pl]
Example 4. Update files for languages defined in LINGUAS file. The files are updated from
messages.pot template:
# ...
env.POUpdate(LINGUAS_FILE = 1) # needs 'LINGUAS' file
Example 5. Same as above, but update from foo.pot template:
# ...
env.POUpdate(LINGUAS_FILE = 1, source = ['foo'])
Example 6. Update en.po and pl.po plus files for languages defined in LINGUAS file. The files are
updated from messages.pot template:
# produce 'en.po', 'pl.po' + files defined in 'LINGUAS':
env.POUpdate(['en', 'pl' ], LINGUAS_FILE = 1)
Example 7. Use $POAUTOINIT to automatically initialize PO file if it doesn't exist:
# ...
env.POUpdate(LINGUAS_FILE = 1, POAUTOINIT = 1)
Example 8. Update PO files for languages defined in LINGUAS file. The files are updated from
foo.pot template. All necessary settings are pre-configured via environment.
# ...
env['POAUTOINIT'] = 1
env['LINGUAS_FILE'] = 1
env['POTDOMAIN'] = 'foo'
env.POUpdate()
Program()
env.Program()
Builds an executable given one or more object files or C, C++, D, or Fortran source files. If any
C, C++, D or Fortran source files are specified, then they will be automatically compiled to
object files using the Object() builder method; see that builder method's description for a list
of legal source file suffixes and how they are interpreted. The target executable file prefix
(specified by the $PROGPREFIX construction variable; nothing by default) and suffix (specified by
the $PROGSUFFIX construction variable; by default, .exe on Windows systems, nothing on POSIX
systems) are automatically added to the target if not already present. Example:
env.Program(target = 'foo', source = ['foo.o', 'bar.c', 'baz.f'])
RES()
env.RES()
Builds a Microsoft Visual C++ resource file. This builder method is only provided when Microsoft
Visual C++ or MinGW is being used as the compiler. The .res (or .o for MinGW) suffix is added to
the target name if no other suffix is given. The source file is scanned for implicit dependencies
as though it were a C file. Example:
env.RES('resource.rc')
RMIC()
env.RMIC()
Builds stub and skeleton class files for remote objects from Java .class files. The target is a
directory relative to which the stub and skeleton class files will be written. The source can be
the names of .class files, or the objects return from the Java() builder method.
If the construction variable $JAVACLASSDIR is set, either in the environment or in the call to the
RMIC() builder method itself, then the value of the variable will be stripped from the beginning
of any .class file names.
classes = env.Java(target = 'classdir', source = 'src')
env.RMIC(target = 'outdir1', source = classes)
env.RMIC(target = 'outdir2',
source = ['package/foo.class', 'package/bar.class'])
env.RMIC(target = 'outdir3',
source = ['classes/foo.class', 'classes/bar.class'],
JAVACLASSDIR = 'classes')
RPCGenClient()
env.RPCGenClient()
Generates an RPC client stub (_clnt.c) file from a specified RPC (.x) source file. Because rpcgen
only builds output files in the local directory, the command will be executed in the source file's
directory by default.
# Builds src/rpcif_clnt.c
env.RPCGenClient('src/rpcif.x')
RPCGenHeader()
env.RPCGenHeader()
Generates an RPC header (.h) file from a specified RPC (.x) source file. Because rpcgen only
builds output files in the local directory, the command will be executed in the source file's
directory by default.
# Builds src/rpcif.h
env.RPCGenHeader('src/rpcif.x')
RPCGenService()
env.RPCGenService()
Generates an RPC server-skeleton (_svc.c) file from a specified RPC (.x) source file. Because
rpcgen only builds output files in the local directory, the command will be executed in the source
file's directory by default.
# Builds src/rpcif_svc.c
env.RPCGenClient('src/rpcif.x')
RPCGenXDR()
env.RPCGenXDR()
Generates an RPC XDR routine (_xdr.c) file from a specified RPC (.x) source file. Because rpcgen
only builds output files in the local directory, the command will be executed in the source file's
directory by default.
# Builds src/rpcif_xdr.c
env.RPCGenClient('src/rpcif.x')
SharedLibrary()
env.SharedLibrary()
Builds a shared library (.so on a POSIX system, .dll on Windows) given one or more object files or
C, C++, D or Fortran source files. If any source files are given, then they will be automatically
compiled to object files. The static library prefix and suffix (if any) are automatically added
to the target. The target library file prefix (specified by the $SHLIBPREFIX construction
variable; by default, lib on POSIX systems, nothing on Windows systems) and suffix (specified by
the $SHLIBSUFFIX construction variable; by default, .dll on Windows systems, .so on POSIX systems)
are automatically added to the target if not already present. Example:
env.SharedLibrary(target = 'bar', source = ['bar.c', 'foo.o'])
On Windows systems, the SharedLibrary() builder method will always build an import (.lib) library
in addition to the shared (.dll) library, adding a .lib library with the same basename if there is
not already a .lib file explicitly listed in the targets.
Any object files listed in the source must have been built for a shared library (that is, using
the SharedObject() builder method). scons will raise an error if there is any mismatch.
On some platforms, there is a distinction between a shared library (loaded automatically by the
system to resolve external references) and a loadable module (explicitly loaded by user action).
For maximum portability, use the LoadableModule() builder for the latter.
When the $SHLIBVERSION construction variable is defined a versioned shared library is created.
This modifies the $SHLINKFLAGS as required, adds the version number to the library name, and
creates the symlinks that are needed. $SHLIBVERSION needs to be of the form X.Y.Z, where X and Y
are numbers, and Z is a number but can also contain letters to designate alpha, beta, or release
candidate patch levels.
This builder may create multiple links to the library. On a POSIX system, for the shared library
libbar.so.2.3.1, the links created would be libbar.so, libbar.so.2, and libbar.so.2.3; on a Darwin
(OSX) system the library would be libbar.2.3.1.dylib and the link would be libbar.dylib.
On Windows systems, specifying register=1 will cause the .dll to be registered after it is built
using REGSVR32. The command that is run ("regsvr32" by default) is determined by $REGSVR
construction variable, and the flags passed are determined by $REGSVRFLAGS. By default,
$REGSVRFLAGS includes the /s option, to prevent dialogs from popping up and requiring user
attention when it is run. If you change $REGSVRFLAGS, be sure to include the /s option. For
example,
env.SharedLibrary(target = 'bar',
source = ['bar.cxx', 'foo.obj'],
register=1)
will register bar.dll as a COM object when it is done linking it.
SharedObject()
env.SharedObject()
Builds an object file for inclusion in a shared library. Source files must have one of the same
set of extensions specified above for the StaticObject() builder method. On some platforms
building a shared object requires additional compiler option (e.g. -fPIC for gcc) in addition to
those needed to build a normal (static) object, but on some platforms there is no difference
between a shared object and a normal (static) one. When there is a difference, SCons will only
allow shared objects to be linked into a shared library, and will use a different suffix for
shared objects. On platforms where there is no difference, SCons will allow both normal (static)
and shared objects to be linked into a shared library, and will use the same suffix for shared and
normal (static) objects. The target object file prefix (specified by the $SHOBJPREFIX
construction variable; by default, the same as $OBJPREFIX) and suffix (specified by the
$SHOBJSUFFIX construction variable) are automatically added to the target if not already present.
Examples:
env.SharedObject(target = 'ddd', source = 'ddd.c')
env.SharedObject(target = 'eee.o', source = 'eee.cpp')
env.SharedObject(target = 'fff.obj', source = 'fff.for')
Note that the source files will be scanned according to the suffix mappings in the
SourceFileScanner object. See the section "Scanner Objects," below, for more information.
StaticLibrary()
env.StaticLibrary()
Builds a static library given one or more object files or C, C++, D or Fortran source files. If
any source files are given, then they will be automatically compiled to object files. The static
library prefix and suffix (if any) are automatically added to the target. The target library file
prefix (specified by the $LIBPREFIX construction variable; by default, lib on POSIX systems,
nothing on Windows systems) and suffix (specified by the $LIBSUFFIX construction variable; by
default, .lib on Windows systems, .a on POSIX systems) are automatically added to the target if
not already present. Example:
env.StaticLibrary(target = 'bar', source = ['bar.c', 'foo.o'])
Any object files listed in the source must have been built for a static library (that is, using
the StaticObject() builder method). scons will raise an error if there is any mismatch.
StaticObject()
env.StaticObject()
Builds a static object file from one or more C, C++, D, or Fortran source files. Source files
must have one of the following extensions:
.asm assembly language file
.ASM assembly language file
.c C file
.C Windows: C file
POSIX: C++ file
.cc C++ file
.cpp C++ file
.cxx C++ file
.cxx C++ file
.c++ C++ file
.C++ C++ file
.d D file
.f Fortran file
.F Windows: Fortran file
POSIX: Fortran file + C pre-processor
.for Fortran file
.FOR Fortran file
.fpp Fortran file + C pre-processor
.FPP Fortran file + C pre-processor
.m Object C file
.mm Object C++ file
.s assembly language file
.S Windows: assembly language file
ARM: CodeSourcery Sourcery Lite
.sx assembly language file + C pre-processor
POSIX: assembly language file + C pre-processor
.spp assembly language file + C pre-processor
.SPP assembly language file + C pre-processor
The target object file prefix (specified by the $OBJPREFIX construction variable; nothing by
default) and suffix (specified by the $OBJSUFFIX construction variable; .obj on Windows systems,
.o on POSIX systems) are automatically added to the target if not already present. Examples:
env.StaticObject(target = 'aaa', source = 'aaa.c')
env.StaticObject(target = 'bbb.o', source = 'bbb.c++')
env.StaticObject(target = 'ccc.obj', source = 'ccc.f')
Note that the source files will be scanned according to the suffix mappings in SourceFileScanner
object. See the section "Scanner Objects," below, for more information.
Substfile()
env.Substfile()
The Substfile() builder generates a single text file by concatenating the source files. Nested
lists of sources are flattened. $LINESEPARATOR is used to separate the source files; see the
description of Textfile() for details.
If a single source file is present with an .in suffix, the suffix is stripped and the remainder is
used as the default target name.
The prefix and suffix specified by the $SUBSTFILEPREFIX and $SUBSTFILESUFFIX construction
variables (the null string by default in both cases) are automatically added to the target if they
are not already present.
If a construction variable named $SUBST_DICT is present, it may be either a Python dictionary or a
sequence of (key,value) tuples. If the former, the dictionary is converted into a list of tuples
in an arbitrary order, so if one key is a prefix of another key or if one substitution could be
further expanded by another subsitition, it is unpredictible whether the expansion will occur.
Any occurences in the source of a key are replaced by the corresponding value, which may be a
Python callable function or a string. If a value is a function, it is first called (with no
arguments) to produce a string. The string is subst-expanded and the result replaces the key.
env = Environment(tools = ['default', 'textfile'])
env['prefix'] = '/usr/bin'
script_dict = {'@prefix@': '/bin', @exec_prefix@: '$prefix'}
env.Substfile('script.in', SUBST_DICT = script_dict)
conf_dict = {'%VERSION%': '1.2.3', '%BASE%': 'MyProg'}
env.Substfile('config.h.in', conf_dict, SUBST_DICT = conf_dict)
# UNPREDICTABLE - one key is a prefix of another
bad_foo = {'$foo': '$foo', '$foobar': '$foobar'}
env.Substfile('foo.in', SUBST_DICT = bad_foo)
# PREDICTABLE - keys are applied longest first
good_foo = [('$foobar', '$foobar'), ('$foo', '$foo')]
env.Substfile('foo.in', SUBST_DICT = good_foo)
# UNPREDICTABLE - one substitution could be futher expanded
bad_bar = {'@bar@': '@soap@', '@soap@': 'lye'}
env.Substfile('bar.in', SUBST_DICT = bad_bar)
# PREDICTABLE - substitutions are expanded in order
good_bar = (('@bar@', '@soap@'), ('@soap@', 'lye'))
env.Substfile('bar.in', SUBST_DICT = good_bar)
# the SUBST_DICT may be in common (and not an override)
substutions = {}
subst = Environment(tools = ['textfile'], SUBST_DICT = substitutions)
substitutions['@foo@'] = 'foo'
subst['SUBST_DICT']['@bar@'] = 'bar'
subst.Substfile('pgm1.c', [Value('#include "@foo@.h"'),
Value('#include "@bar@.h"'),
"common.in",
"pgm1.in"
])
subst.Substfile('pgm2.c', [Value('#include "@foo@.h"'),
Value('#include "@bar@.h"'),
"common.in",
"pgm2.in"
])
Tar()
env.Tar()
Builds a tar archive of the specified files and/or directories. Unlike most builder methods, the
Tar() builder method may be called multiple times for a given target; each additional call adds to
the list of entries that will be built into the archive. Any source directories will be scanned
for changes to any on-disk files, regardless of whether or not scons knows about them from other
Builder or function calls.
env.Tar('src.tar', 'src')
# Create the stuff.tar file.
env.Tar('stuff', ['subdir1', 'subdir2'])
# Also add "another" to the stuff.tar file.
env.Tar('stuff', 'another')
# Set TARFLAGS to create a gzip-filtered archive.
env = Environment(TARFLAGS = '-c -z')
env.Tar('foo.tar.gz', 'foo')
# Also set the suffix to .tgz.
env = Environment(TARFLAGS = '-c -z',
TARSUFFIX = '.tgz')
env.Tar('foo')
Textfile()
env.Textfile()
The Textfile() builder generates a single text file. The source strings constitute the lines;
nested lists of sources are flattened. $LINESEPARATOR is used to separate the strings.
If present, the $SUBST_DICT construction variable is used to modify the strings before they are
written; see the Substfile() description for details.
The prefix and suffix specified by the $TEXTFILEPREFIX and $TEXTFILESUFFIX construction variables
(the null string and .txt by default, respectively) are automatically added to the target if they
are not already present. Examples:
# builds/writes foo.txt
env.Textfile(target = 'foo.txt', source = ['Goethe', 42, 'Schiller'])
# builds/writes bar.txt
env.Textfile(target = 'bar',
source = ['lalala', 'tanteratei'],
LINESEPARATOR='|*')
# nested lists are flattened automatically
env.Textfile(target = 'blob',
source = ['lalala', ['Goethe', 42 'Schiller'], 'tanteratei'])
# files may be used as input by wraping them in File()
env.Textfile(target = 'concat', # concatenate files with a marker between
source = [File('concat1'), File('concat2')],
LINESEPARATOR = '====================\n')
Results are:
foo.txt
....8<----
Goethe
42
Schiller
....8<---- (no linefeed at the end)
bar.txt:
....8<----
lalala|*tanteratei
....8<---- (no linefeed at the end)
blob.txt
....8<----
lalala
Goethe
42
Schiller
tanteratei
....8<---- (no linefeed at the end)
Translate()
env.Translate()
This pseudo-builder belongs to &t-link-gettext; toolset. The builder extracts internationalized
messages from source files, updates POT template (if necessary) and then updates PO translations
(if necessary). If $POAUTOINIT is set, missing PO files will be automatically created (i.e.
without translator person intervention). The variables $LINGUAS_FILE and $POTDOMAIN are taken
into acount too. All other construction variables used by POTUpdate(), and POUpdate() work here
too.
Example1. The simplest way is to specify input files and output languages inline in a SCons
script when invoking Translate()
# SConscript in 'po/' directory
env = Environment( tools = ["default", "gettext"] )
env['POAUTOINIT'] = 1
env.Translate(['en','pl'], ['../a.cpp','../b.cpp'])
Example2. If you wish, you may also stick to conventional style known from
<productname>autotools</productname>, i.e. using POTFILES.in and LINGUAS files
# LINGUAS
en pl
#end
# POTFILES.in
a.cpp
b.cpp
# end
# SConscript
env = Environment( tools = ["default", "gettext"] )
env['POAUTOINIT'] = 1
env['XGETTEXTPATH'] = ['../']
env.Translate(LINGUAS_FILE = 1, XGETTEXTFROM = 'POTFILES.in')
The last approach is perhaps the recommended one. It allows easily split
internationalization/localization onto separate SCons scripts, where a script in source tree is
responsible for translations (from sources to PO files) and script(s) under variant directories
are responsible for compilation of PO to MO files to and for installation of MO files. The "gluing
factor" synchronizing these two scripts is then the content of LINGUAS file. Note, that the
updated POT and PO files are usually going to be committed back to the repository, so they must be
updated within the source directory (and not in variant directories). Additionally, the file
listing of po/ directory contains LINGUAS file, so the source tree looks familiar to translators,
and they may work with the project in their usual way.
Example3. Let's prepare a development tree as below
project/
+ SConstruct
+ build/
+ src/
+ po/
+ SConscript
+ SConscript.i18n
+ POTFILES.in
+ LINGUAS
with build being variant directory. Write the top-level SConstruct script as follows
# SConstruct
env = Environment( tools = ["default", "gettext"] )
VariantDir('build', 'src', duplicate = 0)
env['POAUTOINIT'] = 1
SConscript('src/po/SConscript.i18n', exports = 'env')
SConscript('build/po/SConscript', exports = 'env')
the src/po/SConscript.i18n as
# src/po/SConscript.i18n
Import('env')
env.Translate(LINGUAS_FILE=1, XGETTEXTFROM='POTFILES.in', XGETTEXTPATH=['../'])
and the src/po/SConscript
# src/po/SConscript
Import('env')
env.MOFiles(LINGUAS_FILE = 1)
Such setup produces POT and PO files under source tree in src/po/ and binary MO files under variant tree
in build/po/. This way the POT and PO files are separated from other output files, which must not be
committed back to source repositories (e.g. MO files).
<note> In above example, the PO files are not updated, nor created automatically when you issue scons '.'
command. The files must be updated (created) by hand via scons po-update and then MO files can be
compiled by running scons '.'.</para></note>
TypeLibrary()
env.TypeLibrary()
Builds a Windows type library (.tlb) file from an input IDL file (.idl). In addition, it will
build the associated inteface stub and proxy source files, naming them according to the base name
of the .idl file. For example,
env.TypeLibrary(source="foo.idl")
Will create foo.tlb, foo.h, foo_i.c, foo_p.c and foo_data.c files.
Uic()
env.Uic()
Builds a header file, an implementation file and a moc file from an ui file. and returns the
corresponding nodes in the above order. This builder is only available after using the tool 'qt'.
Note: you can specify .ui files directly as source files to the Program(), Library() and
SharedLibrary() builders without using this builder. Using this builder lets you override the
standard naming conventions (be careful: prefixes are always prepended to names of built files; if
you don't want prefixes, you may set them to ``). See the $QTDIR variable for more information.
Example:
env.Uic('foo.ui') # -> ['foo.h', 'uic_foo.cc', 'moc_foo.cc']
env.Uic(target = Split('include/foo.h gen/uicfoo.cc gen/mocfoo.cc'),
source = 'foo.ui') # -> ['include/foo.h', 'gen/uicfoo.cc', 'gen/mocfoo.cc']
Zip()
env.Zip()
Builds a zip archive of the specified files and/or directories. Unlike most builder methods, the
Zip() builder method may be called multiple times for a given target; each additional call adds to
the list of entries that will be built into the archive. Any source directories will be scanned
for changes to any on-disk files, regardless of whether or not scons knows about them from other
Builder or function calls.
env.Zip('src.zip', 'src')
# Create the stuff.zip file.
env.Zip('stuff', ['subdir1', 'subdir2'])
# Also add "another" to the stuff.tar file.
env.Zip('stuff', 'another')
All targets of builder methods automatically depend on their sources. An explicit dependency can be
specified using the Depends method of a construction environment (see below).
In addition, scons automatically scans source files for various programming languages, so the
dependencies do not need to be specified explicitly. By default, SCons can C source files, C++ source
files, Fortran source files with .F (POSIX systems only), .fpp, or .FPP file extensions, and assembly
language files with .S (POSIX systems only), .spp, or .SPP files extensions for C preprocessor
dependencies. SCons also has default support for scanning D source files, You can also write your own
Scanners to add support for additional source file types. These can be added to the default Scanner
object used by the Object(), StaticObject(), and SharedObject() Builders by adding them to the
SourceFileScanner object. See the section "Scanner Objects" below, for more information about defining
your own Scanner objects and using the SourceFileScanner object.
Methods and Functions to Do Things
In addition to Builder methods, scons provides a number of other construction environment methods and
global functions to manipulate the build configuration.
Usually, a construction environment method and global function with the same name both exist so that you
don't have to remember whether to a specific bit of functionality must be called with or without a
construction environment. In the following list, if you call something as a global function it looks
like:
Function(arguments)
and if you call something through a construction environment it looks like:
env.Function(arguments)
If you can call the functionality in both ways, then both forms are listed.
Global functions may be called from custom Python modules that you import into an SConscript file by
adding the following to the Python module:
from SCons.Script import *
Except where otherwise noted, the same-named construction environment method and global function provide
the exact same functionality. The only difference is that, where appropriate, calling the functionality
through a construction environment will substitute construction variables into any supplied strings. For
example:
env = Environment(FOO = 'foo')
Default('$FOO')
env.Default('$FOO')
In the above example, the first call to the global Default() function will actually add a target named
$FOO to the list of default targets, while the second call to the env.Default() construction environment
method will expand the value and add a target named foo to the list of default targets. For more on
construction variable expansion, see the next section on construction variables.
Construction environment methods and global functions supported by scons include:
Action(action, [cmd/str/fun, [var, ...]] [option=value, ...])
env.Action(action, [cmd/str/fun, [var, ...]] [option=value, ...])
Creates an Action object for the specified action. See the section "Action Objects," below, for a
complete explanation of the arguments and behavior.
Note that the env.Action() form of the invocation will expand construction variables in any
argument strings, including the action argument, at the time it is called using the construction
variables in the env construction environment through which env.Action() was called. The Action()
form delays all variable expansion until the Action object is actually used.
AddMethod(object, function, [name])
env.AddMethod(function, [name])
When called with the AddMethod() form, adds the specified function to the specified object as the
specified method name. When called with the env.AddMethod() form, adds the specified function to
the construction environment env as the specified method name. In both cases, if name is omitted
or None, the name of the specified function itself is used for the method name.
Examples:
# Note that the first argument to the function to
# be attached as a method must be the object through
# which the method will be called; the Python
# convention is to call it 'self'.
def my_method(self, arg):
print "my_method() got", arg
# Use the global AddMethod() function to add a method
# to the Environment class. This
AddMethod(Environment, my_method)
env = Environment()
env.my_method('arg')
# Add the function as a method, using the function
# name for the method call.
env = Environment()
env.AddMethod(my_method, 'other_method_name')
env.other_method_name('another arg')
AddOption(arguments)
This function adds a new command-line option to be recognized. The specified arguments are the
same as supported by the standard Python optparse.add_option() method (with a few additional
capabilities noted below); see the documentation for optparse for a thorough discussion of its
option-processing capabities.
In addition to the arguments and values supported by the optparse.add_option() method, the SCons
AddOption() function allows you to set the nargs keyword value to '?' (a string with just the
question mark) to indicate that the specified long option(s) take(s) an optional argument. When
nargs = '?' is passed to the AddOption() function, the const keyword argument may be used to
supply the "default" value that should be used when the option is specified on the command line
without an explicit argument.
If no default= keyword argument is supplied when calling AddOption(), the option will have a
default value of None.
Once a new command-line option has been added with AddOption(), the option value may be accessed
using GetOption() or env.GetOption(). The value may also be set, using SetOption() or
env.SetOption(), if conditions in a SConscript require overriding any default value. Note,
however, that a value specified on the command line will always override a value set by any
SConscript file.
Any specified help= strings for the new option(s) will be displayed by the -H or -h options (the
latter only if no other help text is specified in the SConscript files). The help text for the
local options specified by AddOption() will appear below the SCons options themselves, under a
separate Local Options heading. The options will appear in the help text in the order in which
the AddOption() calls occur.
Example:
AddOption('--prefix',
dest='prefix',
nargs=1, type='string',
action='store',
metavar='DIR',
help='installation prefix')
env = Environment(PREFIX = GetOption('prefix'))
AddPostAction(target, action)
env.AddPostAction(target, action)
Arranges for the specified action to be performed after the specified target has been built. The
specified action(s) may be an Action object, or anything that can be converted into an Action
object (see below).
When multiple targets are supplied, the action may be called multiple times, once after each
action that generates one or more targets in the list.
AddPreAction(target, action)
env.AddPreAction(target, action)
Arranges for the specified action to be performed before the specified target is built. The
specified action(s) may be an Action object, or anything that can be converted into an Action
object (see below).
When multiple targets are specified, the action(s) may be called multiple times, once before each
action that generates one or more targets in the list.
Note that if any of the targets are built in multiple steps, the action will be invoked just
before the "final" action that specifically generates the specified target(s). For example, when
building an executable program from a specified source .c file via an intermediate object file:
foo = Program('foo.c')
AddPreAction(foo, 'pre_action')
The specified pre_action would be executed before scons calls the link command that actually
generates the executable program binary foo, not before compiling the foo.c file into an object
file.
Alias(alias, [targets, [action]])
env.Alias(alias, [targets, [action]])
Creates one or more phony targets that expand to one or more other targets. An optional action
(command) or list of actions can be specified that will be executed whenever the any of the alias
targets are out-of-date. Returns the Node object representing the alias, which exists outside of
any file system. This Node object, or the alias name, may be used as a dependency of any other
target, including another alias. Alias() can be called multiple times for the same alias to add
additional targets to the alias, or additional actions to the list for this alias.
Examples:
Alias('install')
Alias('install', '/usr/bin')
Alias(['install', 'install-lib'], '/usr/local/lib')
env.Alias('install', ['/usr/local/bin', '/usr/local/lib'])
env.Alias('install', ['/usr/local/man'])
env.Alias('update', ['file1', 'file2'], "update_database $SOURCES")
AllowSubstExceptions([exception, ...])
Specifies the exceptions that will be allowed when expanding construction variables. By default,
any construction variable expansions that generate a NameError or IndexError exception will expand
to a '' (a null string) and not cause scons to fail. All exceptions not in the specified list
will generate an error message and terminate processing.
If AllowSubstExceptions() is called multiple times, each call completely overwrites the previous
list of allowed exceptions.
Example:
# Requires that all construction variable names exist.
# (You may wish to do this if you want to enforce strictly
# that all construction variables must be defined before use.)
AllowSubstExceptions()
# Also allow a string containing a zero-division expansion
# like '${1 / 0}' to evalute to ''.
AllowSubstExceptions(IndexError, NameError, ZeroDivisionError)
AlwaysBuild(target, ...)
env.AlwaysBuild(target, ...)
Marks each given target so that it is always assumed to be out of date, and will always be rebuilt
if needed. Note, however, that AlwaysBuild() does not add its target(s) to the default target
list, so the targets will only be built if they are specified on the command line, or are a
dependent of a target specified on the command line--but they will always be built if so
specified. Multiple targets can be passed in to a single call to AlwaysBuild().
env.Append(key=val, [...])
Appends the specified keyword arguments to the end of construction variables in the environment.
If the Environment does not have the specified construction variable, it is simply added to the
environment. If the values of the construction variable and the keyword argument are the same
type, then the two values will be simply added together. Otherwise, the construction variable and
the value of the keyword argument are both coerced to lists, and the lists are added together.
(See also the Prepend method, below.)
Example:
env.Append(CCFLAGS = ' -g', FOO = ['foo.yyy'])
env.AppendENVPath(name, newpath, [envname, sep, delete_existing])
This appends new path elements to the given path in the specified external environment (ENV by
default). This will only add any particular path once (leaving the last one it encounters and
ignoring the rest, to preserve path order), and to help assure this, will normalize all paths
(using os.path.normpath and os.path.normcase). This can also handle the case where the given old
path variable is a list instead of a string, in which case a list will be returned instead of a
string.
If delete_existing is 0, then adding a path that already exists will not move it to the end; it
will stay where it is in the list.
Example:
print 'before:',env['ENV']['INCLUDE']
include_path = '/foo/bar:/foo'
env.AppendENVPath('INCLUDE', include_path)
print 'after:',env['ENV']['INCLUDE']
yields:
before: /foo:/biz
after: /biz:/foo/bar:/foo
env.AppendUnique(key=val, [...], delete_existing=0)
Appends the specified keyword arguments to the end of construction variables in the environment.
If the Environment does not have the specified construction variable, it is simply added to the
environment. If the construction variable being appended to is a list, then any value(s) that
already exist in the construction variable will not be added again to the list. However, if
delete_existing is 1, existing matching values are removed first, so existing values in the arg
list move to the end of the list.
Example:
env.AppendUnique(CCFLAGS = '-g', FOO = ['foo.yyy'])
env.BitKeeper()
A factory function that returns a Builder object to be used to fetch source files using BitKeeper.
The returned Builder is intended to be passed to the SourceCode() function.
This function is deprecated. For details, see the entry for the SourceCode() function.
Example:
env.SourceCode('.', env.BitKeeper())
BuildDir(build_dir, src_dir, [duplicate])
env.BuildDir(build_dir, src_dir, [duplicate])
Deprecated synonyms for VariantDir() and env.VariantDir(). The build_dir argument becomes the
variant_dir argument of VariantDir() or env.VariantDir().
Builder(action, [arguments])
env.Builder(action, [arguments])
Creates a Builder object for the specified action. See the section "Builder Objects," below, for
a complete explanation of the arguments and behavior.
Note that the env.Builder() form of the invocation will expand construction variables in any
arguments strings, including the action argument, at the time it is called using the construction
variables in the env construction environment through which env.Builder() was called. The
Builder() form delays all variable expansion until after the Builder object is actually called.
CacheDir(cache_dir)
env.CacheDir(cache_dir)
Specifies that scons will maintain a cache of derived files in cache_dir. The derived files in
the cache will be shared among all the builds using the same CacheDir() call. Specifying a
cache_dir of None disables derived file caching.
Calling env.CacheDir() will only affect targets built through the specified construction
environment. Calling CacheDir() sets a global default that will be used by all targets built
through construction environments that do not have an env.CacheDir() specified.
When a CacheDir() is being used and scons finds a derived file that needs to be rebuilt, it will
first look in the cache to see if a derived file has already been built from identical input files
and an identical build action (as incorporated into the MD5 build signature). If so, scons will
retrieve the file from the cache. If the derived file is not present in the cache, scons will
rebuild it and then place a copy of the built file in the cache (identified by its MD5 build
signature), so that it may be retrieved by other builds that need to build the same derived file
from identical inputs.
Use of a specified CacheDir() may be disabled for any invocation by using the --cache-disable
option.
If the --cache-force option is used, scons will place a copy of all derived files in the cache,
even if they already existed and were not built by this invocation. This is useful to populate a
cache the first time CacheDir() is added to a build, or after using the --cache-disable option.
When using CacheDir(), scons will report, "Retrieved `file' from cache," unless the --cache-show
option is being used. When the --cache-show option is used, scons will print the action that
would have been used to build the file, without any indication that the file was actually
retrieved from the cache. This is useful to generate build logs that are equivalent regardless of
whether a given derived file has been built in-place or retrieved from the cache.
The NoCache() method can be used to disable caching of specific files. This can be useful if
inputs and/or outputs of some tool are impossible to predict or prohibitively large.
Clean(targets, files_or_dirs)
env.Clean(targets, files_or_dirs)
This specifies a list of files or directories which should be removed whenever the targets are
specified with the -c command line option. The specified targets may be a list or an individual
target. Multiple calls to Clean() are legal, and create new targets or add files and directories
to the clean list for the specified targets.
Multiple files or directories should be specified either as separate arguments to the Clean()
method, or as a list. Clean() will also accept the return value of any of the construction
environment Builder methods. Examples:
The related NoClean() function overrides calling Clean() for the same target, and any targets
passed to both functions will not be removed by the -c option.
Examples:
Clean('foo', ['bar', 'baz'])
Clean('dist', env.Program('hello', 'hello.c'))
Clean(['foo', 'bar'], 'something_else_to_clean')
In this example, installing the project creates a subdirectory for the documentation. This
statement causes the subdirectory to be removed if the project is deinstalled.
Clean(docdir, os.path.join(docdir, projectname))
env.Clone([key=val, ...])
Returns a separate copy of a construction environment. If there are any keyword arguments
specified, they are added to the returned copy, overwriting any existing values for the keywords.
Example:
env2 = env.Clone()
env3 = env.Clone(CCFLAGS = '-g')
Additionally, a list of tools and a toolpath may be specified, as in the Environment constructor:
def MyTool(env): env['FOO'] = 'bar'
env4 = env.Clone(tools = ['msvc', MyTool])
The parse_flags keyword argument is also recognized:
# create an environment for compiling programs that use wxWidgets
wx_env = env.Clone(parse_flags = '!wx-config --cflags --cxxflags')
Command(target, source, action, [key=val, ...])
env.Command(target, source, action, [key=val, ...])
Executes a specific action (or list of actions) to build a target file or files. This is more
convenient than defining a separate Builder object for a single special-case build.
As a special case, the source_scanner keyword argument can be used to specify a Scanner object
that will be used to scan the sources. (The global DirScanner object can be used if any of the
sources will be directories that must be scanned on-disk for changes to files that aren't already
specified in other Builder of function calls.)
Any other keyword arguments specified override any same-named existing construction variables.
An action can be an external command, specified as a string, or a callable Python object; see
"Action Objects," below, for more complete information. Also note that a string specifying an
external command may be preceded by an @ (at-sign) to suppress printing the command in question,
or by a - (hyphen) to ignore the exit status of the external command.
Examples:
env.Command('foo.out', 'foo.in',
"$FOO_BUILD < $SOURCES > $TARGET")
env.Command('bar.out', 'bar.in',
["rm -f $TARGET",
"$BAR_BUILD < $SOURCES > $TARGET"],
ENV = {'PATH' : '/usr/local/bin/'})
def rename(env, target, source):
import os
os.rename('.tmp', str(target[0]))
env.Command('baz.out', 'baz.in',
["$BAZ_BUILD < $SOURCES > .tmp",
rename ])
Note that the Command() function will usually assume, by default, that the specified targets
and/or sources are Files, if no other part of the configuration identifies what type of entry it
is. If necessary, you can explicitly specify that targets or source nodes should be treated as
directoriese by using the Dir() or env.Dir() functions.
Examples:
env.Command('ddd.list', Dir('ddd'), 'ls -l $SOURCE > $TARGET')
env['DISTDIR'] = 'destination/directory'
env.Command(env.Dir('$DISTDIR')), None, make_distdir)
(Also note that SCons will usually automatically create any directory necessary to hold a target
file, so you normally don't need to create directories by hand.)
Configure(env, [custom_tests, conf_dir, log_file, config_h])
env.Configure([custom_tests, conf_dir, log_file, config_h])
Creates a Configure object for integrated functionality similar to GNU autoconf. See the section
"Configure Contexts," below, for a complete explanation of the arguments and behavior.
env.Copy([key=val, ...])
A now-deprecated synonym for env.Clone().
env.CVS(repository, module)
A factory function that returns a Builder object to be used to fetch source files from the
specified CVS repository. The returned Builder is intended to be passed to the SourceCode()
function.
This function is deprecated. For details, see the entry for the SourceCode() function.
The optional specified module will be added to the beginning of all repository path names; this
can be used, in essence, to strip initial directory names from the repository path names, so that
you only have to replicate part of the repository directory hierarchy in your local build
directory.
Examples:
# Will fetch foo/bar/src.c
# from /usr/local/CVSROOT/foo/bar/src.c.
env.SourceCode('.', env.CVS('/usr/local/CVSROOT'))
# Will fetch bar/src.c
# from /usr/local/CVSROOT/foo/bar/src.c.
env.SourceCode('.', env.CVS('/usr/local/CVSROOT', 'foo'))
# Will fetch src.c
# from /usr/local/CVSROOT/foo/bar/src.c.
env.SourceCode('.', env.CVS('/usr/local/CVSROOT', 'foo/bar'))
Decider(function)
env.Decider(function)
Specifies that all up-to-date decisions for targets built through this construction environment
will be handled by the specified function. The function can be one of the following strings that
specify the type of decision function to be performed:
timestamp-newer
Specifies that a target shall be considered out of date and rebuilt if the dependency's
timestamp is newer than the target file's timestamp. This is the behavior of the classic
Make utility, and make can be used a synonym for timestamp-newer.
timestamp-match
Specifies that a target shall be considered out of date and rebuilt if the dependency's
timestamp is different than the timestamp recorded the last time the target was built.
This provides behavior very similar to the classic Make utility (in particular, files are
not opened up so that their contents can be checksummed) except that the target will also
be rebuilt if a dependency file has been restored to a version with an earlier timestamp,
such as can happen when restoring files from backup archives.
MD5 Specifies that a target shall be considered out of date and rebuilt if the dependency's
content has changed sine the last time the target was built, as determined be performing
an MD5 checksum on the dependency's contents and comparing it to the checksum recorded
the last time the target was built. content can be used as a synonym for MD5.
MD5-timestamp
Specifies that a target shall be considered out of date and rebuilt if the dependency's
content has changed sine the last time the target was built, except that dependencies
with a timestamp that matches the last time the target was rebuilt will be assumed to be
up-to-date and not rebuilt. This provides behavior very similar to the MD5 behavior of
always checksumming file contents, with an optimization of not checking the contents of
files whose timestamps haven't changed. The drawback is that SCons will not detect if a
file's content has changed but its timestamp is the same, as might happen in an automated
script that runs a build, updates a file, and runs the build again, all within a single
second.
Examples:
# Use exact timestamp matches by default.
Decider('timestamp-match')
# Use MD5 content signatures for any targets built
# with the attached construction environment.
env.Decider('content')
In addition to the above already-available functions, the function argument may be an actual
Python function that takes the following three arguments:
dependency
The Node (file) which should cause the target to be rebuilt if it has "changed" since
the last tme target was built.
target The Node (file) being built. In the normal case, this is what should get rebuilt if the
dependency has "changed."
prev_ni
Stored information about the state of the dependency the last time the target was built.
This can be consulted to match various file characteristics such as the timestamp, size,
or content signature.
The function should return a True (non-zero) value if the dependency has "changed" since the last time
the target was built (indicating that the target should be rebuilt), and False (zero) otherwise
(indicating that the target should not be rebuilt). Note that the decision can be made using whatever
criteria are appopriate. Ignoring some or all of the function arguments is perfectly normal.
Example:
def my_decider(dependency, target, prev_ni):
return not os.path.exists(str(target))
env.Decider(my_decider)
Default(targets)
env.Default(targets)
This specifies a list of default targets, which will be built by scons if no explicit targets are
given on the command line. Multiple calls to Default() are legal, and add to the list of default
targets.
Multiple targets should be specified as separate arguments to the Default() method, or as a list.
Default() will also accept the Node returned by any of a construction environment's builder
methods.
Examples:
Default('foo', 'bar', 'baz')
env.Default(['a', 'b', 'c'])
hello = env.Program('hello', 'hello.c')
env.Default(hello)
An argument to Default() of None will clear all default targets. Later calls to Default() will
add to the (now empty) default-target list like normal.
The current list of targets added using the Default() function or method is available in the
DEFAULT_TARGETS list; see below.
DefaultEnvironment([args])
Creates and returns a default construction environment object. This construction environment is
used internally by SCons in order to execute many of the global functions in this list, and to
fetch source files transparently from source code management systems.
Depends(target, dependency)
env.Depends(target, dependency)
Specifies an explicit dependency; the target will be rebuilt whenever the dependency has changed.
Both the specified target and dependency can be a string (usually the path name of a file or
directory) or Node objects, or a list of strings or Node objects (such as returned by a Builder
call). This should only be necessary for cases where the dependency is not caught by a Scanner
for the file.
Example:
env.Depends('foo', 'other-input-file-for-foo')
mylib = env.Library('mylib.c')
installed_lib = env.Install('lib', mylib)
bar = env.Program('bar.c')
# Arrange for the library to be copied into the installation
# directory before trying to build the "bar" program.
# (Note that this is for example only. A "real" library
# dependency would normally be configured through the $LIBS
# and $LIBPATH variables, not using an env.Depends() call.)
env.Depends(bar, installed_lib)
env.Dictionary([vars])
Returns a dictionary object containing copies of all of the construction variables in the
environment. If there are any variable names specified, only the specified construction variables
are returned in the dictionary.
Example:
dict = env.Dictionary()
cc_dict = env.Dictionary('CC', 'CCFLAGS', 'CCCOM')
Dir(name, [directory])
env.Dir(name, [directory])
This returns a Directory Node, an object that represents the specified directory name. name can
be a relative or absolute path. directory is an optional directory that will be used as the
parent directory. If no directory is specified, the current script's directory is used as the
parent.
If name is a list, SCons returns a list of Dir nodes. Construction variables are expanded in
name.
Directory Nodes can be used anywhere you would supply a string as a directory name to a Builder
method or function. Directory Nodes have attributes and methods that are useful in many
situations; see "File and Directory Nodes," below.
env.Dump([key])
Returns a pretty printable representation of the environment. key, if not None, should be a
string containing the name of the variable of interest.
This SConstruct:
env=Environment()
print env.Dump('CCCOM')
will print:
´$CC -c -o $TARGET $CCFLAGS $CPPFLAGS $_CPPDEFFLAGS $_CPPINCFLAGS $SOURCES'
While this SConstruct:
env=Environment()
print env.Dump()
will print:
{ 'AR': 'ar',
'ARCOM': '$AR $ARFLAGS $TARGET $SOURCES\n$RANLIB $RANLIBFLAGS $TARGET',
'ARFLAGS': ['r'],
'AS': 'as',
'ASCOM': '$AS $ASFLAGS -o $TARGET $SOURCES',
'ASFLAGS': [],
...
EnsurePythonVersion(major, minor)
env.EnsurePythonVersion(major, minor)
Ensure that the Python version is at least major.minor. This function will print out an error
message and exit SCons with a non-zero exit code if the actual Python version is not late enough.
Example:
EnsurePythonVersion(2,2)
EnsureSConsVersion(major, minor, [revision])
env.EnsureSConsVersion(major, minor, [revision])
Ensure that the SCons version is at least major.minor, or major.minor.revision. if revision is
specified. This function will print out an error message and exit SCons with a non-zero exit code
if the actual SCons version is not late enough.
Examples:
EnsureSConsVersion(0,14)
EnsureSConsVersion(0,96,90)
Environment([key=value, ...])
env.Environment([key=value, ...])
Return a new construction environment initialized with the specified key=value pairs.
Execute(action, [strfunction, varlist])
env.Execute(action, [strfunction, varlist])
Executes an Action object. The specified action may be an Action object (see the section "Action
Objects," below, for a complete explanation of the arguments and behavior), or it may be a
command-line string, list of commands, or executable Python function, each of which will be
converted into an Action object and then executed. The exit value of the command or return value
of the Python function will be returned.
Note that scons will print an error message if the executed action fails--that is, exits with or
returns a non-zero value. scons will not, however, automatically terminate the build if the
specified action fails. If you want the build to stop in response to a failed Execute() call, you
must explicitly check for a non-zero return value:
Execute(Copy('file.out', 'file.in'))
if Execute("mkdir sub/dir/ectory"):
# The mkdir failed, don't try to build.
Exit(1)
Exit([value])
env.Exit([value])
This tells scons to exit immediately with the specified value. A default exit value of 0 (zero)
is used if no value is specified.
Export(vars)
env.Export(vars)
This tells scons to export a list of variables from the current SConscript file to all other
SConscript files. The exported variables are kept in a global collection, so subsequent calls to
Export() will over-write previous exports that have the same name. Multiple variable names can be
passed to Export() as separate arguments or as a list. Keyword arguments can be used to provide
names and their values. A dictionary can be used to map variables to a different name when
exported. Both local variables and global variables can be exported.
Examples:
env = Environment()
# Make env available for all SConscript files to Import().
Export("env")
package = 'my_name'
# Make env and package available for all SConscript files:.
Export("env", "package")
# Make env and package available for all SConscript files:
Export(["env", "package"])
# Make env available using the name debug:
Export(debug = env)
# Make env available using the name debug:
Export({"debug":env})
Note that the SConscript() function supports an exports argument that makes it easier to to export
a variable or set of variables to a single SConscript file. See the description of the
SConscript() function, below.
File(name, [directory])
env.File(name, [directory])
This returns a File Node, an object that represents the specified file name. name can be a
relative or absolute path. directory is an optional directory that will be used as the parent
directory.
If name is a list, SCons returns a list of File nodes. Construction variables are expanded in
name.
File Nodes can be used anywhere you would supply a string as a file name to a Builder method or
function. File Nodes have attributes and methods that are useful in many situations; see "File
and Directory Nodes," below.
FindFile(file, dirs)
env.FindFile(file, dirs)
Search for file in the path specified by dirs. dirs may be a list of directory names or a single
directory name. In addition to searching for files that exist in the filesystem, this function
also searches for derived files that have not yet been built.
Example:
foo = env.FindFile('foo', ['dir1', 'dir2'])
FindInstalledFiles()
env.FindInstalledFiles()
Returns the list of targets set up by the Install() or InstallAs() builders.
This function serves as a convenient method to select the contents of a binary package.
Example:
Install( '/bin', [ 'executable_a', 'executable_b' ] )
# will return the file node list
# [ '/bin/executable_a', '/bin/executable_b' ]
FindInstalledFiles()
Install( '/lib', [ 'some_library' ] )
# will return the file node list
# [ '/bin/executable_a', '/bin/executable_b', '/lib/some_library' ]
FindInstalledFiles()
FindPathDirs(variable)
Returns a function (actually a callable Python object) intended to be used as the path_function of
a Scanner object. The returned object will look up the specified variable in a construction
environment and treat the construction variable's value as a list of directory paths that should
be searched (like $CPPPATH, $LIBPATH, etc.).
Note that use of FindPathDirs() is generally preferable to writing your own path_function for the
following reasons: 1) The returned list will contain all appropriate directories found in source
trees (when VariantDir() is used) or in code repositories (when Repository() or the -Y option are
used). 2) scons will identify expansions of variable that evaluate to the same list of
directories as, in fact, the same list, and avoid re-scanning the directories for files, when
possible.
Example:
def my_scan(node, env, path, arg):
# Code to scan file contents goes here...
return include_files
scanner = Scanner(name = 'myscanner',
function = my_scan,
path_function = FindPathDirs('MYPATH'))
FindSourceFiles(node='"."')
env.FindSourceFiles(node='"."')
Returns the list of nodes which serve as the source of the built files. It does so by inspecting
the dependency tree starting at the optional argument node which defaults to the '"."'-node. It
will then return all leaves of node. These are all children which have no further children.
This function is a convenient method to select the contents of a Source Package.
Example:
Program( 'src/main_a.c' )
Program( 'src/main_b.c' )
Program( 'main_c.c' )
# returns ['main_c.c', 'src/main_a.c', 'SConstruct', 'src/main_b.c']
FindSourceFiles()
# returns ['src/main_b.c', 'src/main_a.c' ]
FindSourceFiles( 'src' )
As you can see build support files (SConstruct in the above example) will also be returned by this
function.
Flatten(sequence)
env.Flatten(sequence)
Takes a sequence (that is, a Python list or tuple) that may contain nested sequences and returns a
flattened list containing all of the individual elements in any sequence. This can be helpful for
collecting the lists returned by calls to Builders; other Builders will automatically flatten
lists specified as input, but direct Python manipulation of these lists does not.
Examples:
foo = Object('foo.c')
bar = Object('bar.c')
# Because `foo' and `bar' are lists returned by the Object() Builder,
# `objects' will be a list containing nested lists:
objects = ['f1.o', foo, 'f2.o', bar, 'f3.o']
# Passing such a list to another Builder is all right because
# the Builder will flatten the list automatically:
Program(source = objects)
# If you need to manipulate the list directly using Python, you need to
# call Flatten() yourself, or otherwise handle nested lists:
for object in Flatten(objects):
print str(object)
GetBuildFailures()
Returns a list of exceptions for the actions that failed while attempting to build targets. Each
element in the returned list is a BuildError object with the following attributes that record
various aspects of the build failure:
.node The node that was being built when the build failure occurred.
.status The numeric exit status returned by the command or Python function that failed when trying
to build the specified Node.
.errstr The SCons error string describing the build failure. (This is often a generic message
like "Error 2" to indicate that an executed command exited with a status of 2.)
.filename The name of the file or directory that actually caused the failure. This may be
different from the .node attribute. For example, if an attempt to build a target named
sub/dir/target fails because the sub/dir directory could not be created, then the .node attribute
will be sub/dir/target but the .filename attribute will be sub/dir.
.executor The SCons Executor object for the target Node being built. This can be used to retrieve
the construction environment used for the failed action.
.action The actual SCons Action object that failed. This will be one specific action out of the
possible list of actions that would have been executed to build the target.
.command The actual expanded command that was executed and failed, after expansion of $TARGET,
$SOURCE, and other construction variables.
Note that the GetBuildFailures() function will always return an empty list until any build failure
has occurred, which means that GetBuildFailures() will always return an empty list while the
SConscript files are being read. Its primary intended use is for functions that will be executed
before SCons exits by passing them to the standard Python atexit.register() function. Example:
import atexit
def print_build_failures():
from SCons.Script import GetBuildFailures
for bf in GetBuildFailures():
print "%s failed: %s" % (bf.node, bf.errstr)
atexit.register(print_build_failures)
GetBuildPath(file, [...])
env.GetBuildPath(file, [...])
Returns the scons path name (or names) for the specified file (or files). The specified file or
files may be scons Nodes or strings representing path names.
GetLaunchDir()
env.GetLaunchDir()
Returns the absolute path name of the directory from which scons was initially invoked. This can
be useful when using the -u, -U or -D options, which internally change to the directory in which
the SConstruct file is found.
GetOption(name)
env.GetOption(name)
This function provides a way to query the value of SCons options set on scons command line (or set
using the SetOption() function). The options supported are:
cache_debug
which corresponds to --cache-debug;
cache_disable
which corresponds to --cache-disable;
cache_force
which corresponds to --cache-force;
cache_show
which corresponds to --cache-show;
clean which corresponds to -c, --clean and --remove;
config
which corresponds to --config;
directory
which corresponds to -C and --directory;
diskcheck
which corresponds to --diskcheck
duplicate
which corresponds to --duplicate;
file which corresponds to -f, --file, --makefile and --sconstruct;
help which corresponds to -h and --help;
ignore_errors
which corresponds to --ignore-errors;
implicit_cache
which corresponds to --implicit-cache;
implicit_deps_changed
which corresponds to --implicit-deps-changed;
implicit_deps_unchanged
which corresponds to --implicit-deps-unchanged;
interactive
which corresponds to --interact and --interactive;
keep_going
which corresponds to -k and --keep-going;
max_drift
which corresponds to --max-drift;
no_exec
which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
no_site_dir
which corresponds to --no-site-dir;
num_jobs
which corresponds to -j and --jobs;
profile_file
which corresponds to --profile;
question
which corresponds to -q and --question;
random
which corresponds to --random;
repository
which corresponds to -Y, --repository and --srcdir;
silent
which corresponds to -s, --silent and --quiet;
site_dir
which corresponds to --site-dir;
stack_size
which corresponds to --stack-size;
taskmastertrace_file
which corresponds to --taskmastertrace; and
warn which corresponds to --warn and --warning.
See the documentation for the corresponding command line object for information about each specific
option.
Glob(pattern, [ondisk, source, strings])
env.Glob(pattern, [ondisk, source, strings])
Returns Nodes (or strings) that match the specified pattern, relative to the directory of the
current SConscript file. The env.Glob() form performs string substition on pattern and returns
whatever matches the resulting expanded pattern.
The specified pattern uses Unix shell style metacharacters for matching:
* matches everything
? matches any single character
[seq] matches any character in seq
[!seq] matches any char not in seq
If the first character of a filename is a dot, it must be matched explicitly. Character matches
do not span directory separators.
The Glob() knows about repositories (see the Repository() function) and source directories (see
the VariantDir() function) and returns a Node (or string, if so configured) in the local
(SConscript) directory if matching Node is found anywhere in a corresponding repository or source
directory.
The ondisk argument may be set to False (or any other non-true value) to disable the search for
matches on disk, thereby only returning matches among already-configured File or Dir Nodes. The
default behavior is to return corresponding Nodes for any on-disk matches found.
The source argument may be set to True (or any equivalent value) to specify that, when the local
directory is a VariantDir(), the returned Nodes should be from the corresponding source directory,
not the local directory.
The strings argument may be set to True (or any equivalent value) to have the Glob() function
return strings, not Nodes, that represent the matched files or directories. The returned strings
will be relative to the local (SConscript) directory. (Note that This may make it easier to
perform arbitrary manipulation of file names, but if the returned strings are passed to a
different SConscript file, any Node translation will be relative to the other SConscript
directory, not the original SConscript directory.)
Examples:
Program('foo', Glob('*.c'))
Zip('/tmp/everything', Glob('.??*') + Glob('*'))
Help(text)
env.Help(text)
This specifies help text to be printed if the -h argument is given to scons. If Help() is called
multiple times, the text is appended together in the order that Help() is called.
Ignore(target, dependency)
env.Ignore(target, dependency)
The specified dependency file(s) will be ignored when deciding if the target file(s) need to be
rebuilt.
You can also use Ignore() to remove a target from the default build. In order to do this you must
specify the directory the target will be built in as the target, and the file you want to skip
building as the dependency.
Note that this will only remove the dependencies listed from the files built by default. It will
still be built if that dependency is needed by another object being built. See the third and
forth examples below.
Examples:
env.Ignore('foo', 'foo.c')
env.Ignore('bar', ['bar1.h', 'bar2.h'])
env.Ignore('.','foobar.obj')
env.Ignore('bar','bar/foobar.obj')
Import(vars)
env.Import(vars)
This tells scons to import a list of variables into the current SConscript file. This will import
variables that were exported with Export() or in the exports argument to SConscript(). Variables
exported by SConscript() have precedence. Multiple variable names can be passed to Import() as
separate arguments or as a list. The variable "*" can be used to import all variables.
Examples:
Import("env")
Import("env", "variable")
Import(["env", "variable"])
Import("*")
Literal(string)
env.Literal(string)
The specified string will be preserved as-is and not have construction variables expanded.
Local(targets)
env.Local(targets)
The specified targets will have copies made in the local tree, even if an already up-to-date copy
exists in a repository. Returns a list of the target Node or Nodes.
env.MergeFlags(arg, [unique])
Merges the specified arg values to the construction environment's construction variables. If the
arg argument is not a dictionary, it is converted to one by calling env.ParseFlags() on the
argument before the values are merged. Note that arg must be a single value, so multiple strings
must be passed in as a list, not as separate arguments to env.MergeFlags().
By default, duplicate values are eliminated; you can, however, specify unique=0 to allow duplicate
values to be added. When eliminating duplicate values, any construction variables that end with
the string PATH keep the left-most unique value. All other construction variables keep the right-
most unique value.
Examples:
# Add an optimization flag to $CCFLAGS.
env.MergeFlags('-O3')
# Combine the flags returned from running pkg-config with an optimization
# flag and merge the result into the construction variables.
env.MergeFlags(['!pkg-config gtk+-2.0 --cflags', '-O3'])
# Combine an optimization flag with the flags returned from running pkg-config
# twice and merge the result into the construction variables.
env.MergeFlags(['-O3',
'!pkg-config gtk+-2.0 --cflags --libs',
'!pkg-config libpng12 --cflags --libs'])
NoCache(target, ...)
env.NoCache(target, ...)
Specifies a list of files which should not be cached whenever the CacheDir() method has been
activated. The specified targets may be a list or an individual target.
Multiple files should be specified either as separate arguments to the NoCache() method, or as a
list. NoCache() will also accept the return value of any of the construction environment Builder
methods.
Calling NoCache() on directories and other non-File Node types has no effect because only File
Nodes are cached.
Examples:
NoCache('foo.elf')
NoCache(env.Program('hello', 'hello.c'))
NoClean(target, ...)
env.NoClean(target, ...)
Specifies a list of files or directories which should not be removed whenever the targets (or
their dependencies) are specified with the -c command line option. The specified targets may be a
list or an individual target. Multiple calls to NoClean() are legal, and prevent each specified
target from being removed by calls to the -c option.
Multiple files or directories should be specified either as separate arguments to the NoClean()
method, or as a list. NoClean() will also accept the return value of any of the construction
environment Builder methods.
Calling NoClean() for a target overrides calling Clean() for the same target, and any targets
passed to both functions will not be removed by the -c option.
Examples:
NoClean('foo.elf')
NoClean(env.Program('hello', 'hello.c'))
env.ParseConfig(command, [function, unique])
Calls the specified function to modify the environment as specified by the output of command. The
default function is env.MergeFlags(), which expects the output of a typical *-config command (for
example, gtk-config) and adds the options to the appropriate construction variables. By default,
duplicate values are not added to any construction variables; you can specify unique=0 to allow
duplicate values to be added.
Interpreted options and the construction variables they affect are as specified for the
env.ParseFlags() method (which this method calls). See that method's description, below, for a
table of options and construction variables.
ParseDepends(filename, [must_exist, only_one])
env.ParseDepends(filename, [must_exist, only_one])
Parses the contents of the specified filename as a list of dependencies in the style of Make or
mkdep, and explicitly establishes all of the listed dependencies.
By default, it is not an error if the specified filename does not exist. The optional must_exist
argument may be set to a non-zero value to have scons throw an exception and generate an error if
the file does not exist, or is otherwise inaccessible.
The optional only_one argument may be set to a non-zero value to have scons thrown an exception
and generate an error if the file contains dependency information for more than one target. This
can provide a small sanity check for files intended to be generated by, for example, the gcc -M
flag, which should typically only write dependency information for one output file into a
corresponding .d file.
The filename and all of the files listed therein will be interpreted relative to the directory of
the SConscript file which calls the ParseDepends() function.
env.ParseFlags(flags, ...)
Parses one or more strings containing typical command-line flags for GCC tool chains and returns a
dictionary with the flag values separated into the appropriate SCons construction variables. This
is intended as a companion to the env.MergeFlags() method, but allows for the values in the
returned dictionary to be modified, if necessary, before merging them into the construction
environment. (Note that env.MergeFlags() will call this method if its argument is not a
dictionary, so it is usually not necessary to call env.ParseFlags() directly unless you want to
manipulate the values.)
If the first character in any string is an exclamation mark (!), the rest of the string is
executed as a command, and the output from the command is parsed as GCC tool chain command-line
flags and added to the resulting dictionary.
Flag values are translated accordig to the prefix found, and added to the following construction
variables:
-arch CCFLAGS, LINKFLAGS
-D CPPDEFINES
-framework FRAMEWORKS
-frameworkdir= FRAMEWORKPATH
-include CCFLAGS
-isysroot CCFLAGS, LINKFLAGS
-I CPPPATH
-l LIBS
-L LIBPATH
-mno-cygwin CCFLAGS, LINKFLAGS
-mwindows LINKFLAGS
-pthread CCFLAGS, LINKFLAGS
-std= CFLAGS
-Wa, ASFLAGS, CCFLAGS
-Wl,-rpath= RPATH
-Wl,-R, RPATH
-Wl,-R RPATH
-Wl, LINKFLAGS
-Wp, CPPFLAGS
- CCFLAGS
+ CCFLAGS, LINKFLAGS
Any other strings not associated with options are assumed to be the names of libraries and added
to the $LIBS construction variable.
Examples (all of which produce the same result):
dict = env.ParseFlags('-O2 -Dfoo -Dbar=1')
dict = env.ParseFlags('-O2', '-Dfoo', '-Dbar=1')
dict = env.ParseFlags(['-O2', '-Dfoo -Dbar=1'])
dict = env.ParseFlags('-O2', '!echo -Dfoo -Dbar=1')
env.Perforce()
A factory function that returns a Builder object to be used to fetch source files from the
Perforce source code management system. The returned Builder is intended to be passed to the
SourceCode() function.
This function is deprecated. For details, see the entry for the SourceCode() function.
Example:
env.SourceCode('.', env.Perforce())
Perforce uses a number of external environment variables for its operation. Consequently, this
function adds the following variables from the user's external environment to the construction
environment's ENV dictionary: P4CHARSET, P4CLIENT, P4LANGUAGE, P4PASSWD, P4PORT, P4USER,
SystemRoot, USER, and USERNAME.
Platform(string)
The Platform() form returns a callable object that can be used to initialize a construction
environment using the platform keyword of the Environment() function.
Example:
env = Environment(platform = Platform('win32'))
The env.Platform() form applies the callable object for the specified platform string to the
environment through which the method was called.
env.Platform('posix')
Note that the win32 platform adds the SystemDrive and SystemRoot variables from the user's
external environment to the construction environment's $ENV dictionary. This is so that any
executed commands that use sockets to connect with other systems (such as fetching source files
from external CVS repository specifications like
:pserver:anonymous@cvs.sourceforge.net:/cvsroot/scons) will work on Windows systems.
Precious(target, ...)
env.Precious(target, ...)
Marks each given target as precious so it is not deleted before it is rebuilt. Normally scons
deletes a target before building it. Multiple targets can be passed in to a single call to
Precious().
env.Prepend(key=val, [...])
Appends the specified keyword arguments to the beginning of construction variables in the
environment. If the Environment does not have the specified construction variable, it is simply
added to the environment. If the values of the construction variable and the keyword argument are
the same type, then the two values will be simply added together. Otherwise, the construction
variable and the value of the keyword argument are both coerced to lists, and the lists are added
together. (See also the Append method, above.)
Example:
env.Prepend(CCFLAGS = '-g ', FOO = ['foo.yyy'])
env.PrependENVPath(name, newpath, [envname, sep, delete_existing])
This appends new path elements to the given path in the specified external environment ($ENV by
default). This will only add any particular path once (leaving the first one it encounters and
ignoring the rest, to preserve path order), and to help assure this, will normalize all paths
(using os.path.normpath and os.path.normcase). This can also handle the case where the given old
path variable is a list instead of a string, in which case a list will be returned instead of a
string.
If delete_existing is 0, then adding a path that already exists will not move it to the beginning;
it will stay where it is in the list.
Example:
print 'before:',env['ENV']['INCLUDE']
include_path = '/foo/bar:/foo'
env.PrependENVPath('INCLUDE', include_path)
print 'after:',env['ENV']['INCLUDE']
The above example will print:
before: /biz:/foo
after: /foo/bar:/foo:/biz
env.PrependUnique(key=val, delete_existing=0, [...])
Appends the specified keyword arguments to the beginning of construction variables in the
environment. If the Environment does not have the specified construction variable, it is simply
added to the environment. If the construction variable being appended to is a list, then any
value(s) that already exist in the construction variable will not be added again to the list.
However, if delete_existing is 1, existing matching values are removed first, so existing values
in the arg list move to the front of the list.
Example:
env.PrependUnique(CCFLAGS = '-g', FOO = ['foo.yyy'])
Progress(callable, [interval])
Progress(string, [interval, file, overwrite])
Progress(list_of_strings, [interval, file, overwrite])
Allows SCons to show progress made during the build by displaying a string or calling a function
while evaluating Nodes (e.g. files).
If the first specified argument is a Python callable (a function or an object that has a
__call__() method), the function will be called once every interval times a Node is evaluated.
The callable will be passed the evaluated Node as its only argument. (For future compatibility,
it's a good idea to also add *args and **kw as arguments to your function or method. This will
prevent the code from breaking if SCons ever changes the interface to call the function with
additional arguments in the future.)
An example of a simple custom progress function that prints a string containing the Node name
every 10 Nodes:
def my_progress_function(node, *args, **kw):
print 'Evaluating node %s!' % node
Progress(my_progress_function, interval=10)
A more complicated example of a custom progress display (ajcarriage return)aattthegendosoathatgthe
count every 100 evaluated Nodes. Note the use of
string will overwrite itself on a display:
import sys
class ProgressCounter(object):
count = 0
def __call__(self, node, *args, **kw):
self.count += 100
sys.stderr.write('Evaluated %s nodes\r' % self.count)
Progress(ProgressCounter(), interval=100)
If the first argument Progress() is a string, the string will be displayed every interval
evaluated Nodes. The default is to print the string on standard output; an alternate output
stream may be specified with the file= argument. The following will print a series of dots on the
error output, one dot for every 100 evaluated Nodes:
import sys
Progress('.', interval=100, file=sys.stderr)
If the string contains the verbatim substring $TARGET, it will be replaced with the Node. Note
that, for performance reasons, this is not a regular SCons variable substition, so you can not use
other variables or (carriage breturn) Tto causeweachelineltowoverwrittenhbynthe nextvline,vandathe
Node, using a
overwrite= keyword argument to make sure the previously-printed file name is overwritten with
blank spaces:
import sys
Progress('$TARGET\r', overwrite=True)
If the first argument to Progress() is a list of strings, then each string in the list will be
displayed in rotating fashion every interval evaluated Nodes. This can be used to implement a
"spinner" on the user's screen as follows:
Progress(['-\r', '\\\r', '|\r', '/\r'], interval=5)
env.RCS()
A factory function that returns a Builder object to be used to fetch source files from RCS. The
returned Builder is intended to be passed to the SourceCode() function:
This function is deprecated. For details, see the entry for the SourceCode() function.
Examples:
env.SourceCode('.', env.RCS())
Note that scons will fetch source files from RCS subdirectories automatically, so configuring RCS
as demonstrated in the above example should only be necessary if you are fetching from RCS,v files
in the same directory as the source files, or if you need to explicitly specify RCS for a specific
subdirectory.
env.Replace(key=val, [...])
Replaces construction variables in the Environment with the specified keyword arguments.
Example:
env.Replace(CCFLAGS = '-g', FOO = 'foo.xxx')
Repository(directory)
env.Repository(directory)
Specifies that directory is a repository to be searched for files. Multiple calls to Repository()
are legal, and each one adds to the list of repositories that will be searched.
To scons, a repository is a copy of the source tree, from the top-level directory on down, which
may contain both source files and derived files that can be used to build targets in the local
source tree. The canonical example would be an official source tree maintained by an integrator.
If the repository contains derived files, then the derived files should have been built using
scons, so that the repository contains the necessary signature information to allow scons to
figure out when it is appropriate to use the repository copy of a derived file, instead of
building one locally.
Note that if an up-to-date derived file already exists in a repository, scons will not make a copy
in the local directory tree. In order to guarantee that a local copy will be made, use the
Local() method.
Requires(target, prerequisite)
env.Requires(target, prerequisite)
Specifies an order-only relationship between the specified target file(s) and the specified
prerequisite file(s). The prerequisite file(s) will be (re)built, if necessary, before the target
file(s), but the target file(s) do not actually depend on the prerequisites and will not be
rebuilt simply because the prerequisite file(s) change.
Example:
env.Requires('foo', 'file-that-must-be-built-before-foo')
Return([vars..., stop=])
By default, this stops processing the current SConscript file and returns to the calling
SConscript file the values of the variables named in the vars string arguments. Multiple strings
contaning variable names may be passed to Return(). Any strings that contain white space
The optional stop= keyword argument may be set to a false value to continue processing the rest of
the SConscript file after the Return() call. This was the default behavior prior to SCons 0.98.
However, the values returned are still the values of the variables in the named vars at the point
Return() is called.
Examples:
# Returns without returning a value.
Return()
# Returns the value of the 'foo' Python variable.
Return("foo")
# Returns the values of the Python variables 'foo' and 'bar'.
Return("foo", "bar")
# Returns the values of Python variables 'val1' and 'val2'.
Return('val1 val2')
Scanner(function, [argument, keys, path_function, node_class, node_factory, scan_check, recursive])
env.Scanner(function, [argument, keys, path_function, node_class, node_factory, scan_check, recursive])
Creates a Scanner object for the specified function. See the section "Scanner Objects," below,
for a complete explanation of the arguments and behavior.
env.SCCS()
A factory function that returns a Builder object to be used to fetch source files from SCCS. The
returned Builder is intended to be passed to the SourceCode() function.
Example:
env.SourceCode('.', env.SCCS())
Note that scons will fetch source files from SCCS subdirectories automatically, so configuring
SCCS as demonstrated in the above example should only be necessary if you are fetching from s.SCCS
files in the same directory as the source files, or if you need to explicitly specify SCCS for a
specific subdirectory.
SConscript(scripts, [exports, variant_dir, duplicate])
env.SConscript(scripts, [exports, variant_dir, duplicate])
SConscript(dirs=subdirs, [name=script, exports, variant_dir, duplicate])
env.SConscript(dirs=subdirs, [name=script, exports, variant_dir, duplicate])
This tells scons to execute one or more subsidiary SConscript (configuration) files. Any
variables returned by a called script using Return() will be returned by the call to SConscript().
There are two ways to call the SConscript() function.
The first way you can call SConscript() is to explicitly specify one or more scripts as the first
argument. A single script may be specified as a string; multiple scripts must be specified as a
list (either explicitly or as created by a function like Split()). Examples:
SConscript('SConscript') # run SConscript in the current directory
SConscript('src/SConscript') # run SConscript in the src directory
SConscript(['src/SConscript', 'doc/SConscript'])
config = SConscript('MyConfig.py')
The second way you can call SConscript() is to specify a list of (sub)directory names as a
dirs=subdirs keyword argument. In this case, scons will, by default, execute a subsidiary
configuration file named SConscript in each of the specified directories. You may specify a name
other than SConscript by supplying an optional name=script keyword argument. The first three
examples below have the same effect as the first three examples above:
SConscript(dirs='.') # run SConscript in the current directory
SConscript(dirs='src') # run SConscript in the src directory
SConscript(dirs=['src', 'doc'])
SConscript(dirs=['sub1', 'sub2'], name='MySConscript')
The optional exports argument provides a list of variable names or a dictionary of named values to
export to the script(s). These variables are locally exported only to the specified script(s),
and do not affect the global pool of variables used by the Export() function. The subsidiary
script(s) must use the Import() function to import the variables. Examples:
foo = SConscript('sub/SConscript', exports='env')
SConscript('dir/SConscript', exports=['env', 'variable'])
SConscript(dirs='subdir', exports='env variable')
SConscript(dirs=['one', 'two', 'three'], exports='shared_info')
If the optional variant_dir argument is present, it causes an effect equivalent to the
VariantDir() method described below. (If variant_dir is not present, the duplicate argument is
ignored.) The variant_dir argument is interpreted relative to the directory of the calling
SConscript file. See the description of the VariantDir() function below for additional details
and restrictions.
If variant_dir is present, the source directory is the directory in which the SConscript file
resides and the SConscript file is evaluated as if it were in the variant_dir directory:
SConscript('src/SConscript', variant_dir = 'build')
is equivalent to
VariantDir('build', 'src')
SConscript('build/SConscript')
This later paradigm is often used when the sources are in the same directory as the SConstruct:
SConscript('SConscript', variant_dir = 'build')
is equivalent to
VariantDir('build', '.')
SConscript('build/SConscript')
Here are some composite examples:
# collect the configuration information and use it to build src and doc
shared_info = SConscript('MyConfig.py')
SConscript('src/SConscript', exports='shared_info')
SConscript('doc/SConscript', exports='shared_info')
# build debugging and production versions. SConscript
# can use Dir('.').path to determine variant.
SConscript('SConscript', variant_dir='debug', duplicate=0)
SConscript('SConscript', variant_dir='prod', duplicate=0)
# build debugging and production versions. SConscript
# is passed flags to use.
opts = { 'CPPDEFINES' : ['DEBUG'], 'CCFLAGS' : '-pgdb' }
SConscript('SConscript', variant_dir='debug', duplicate=0, exports=opts)
opts = { 'CPPDEFINES' : ['NODEBUG'], 'CCFLAGS' : '-O' }
SConscript('SConscript', variant_dir='prod', duplicate=0, exports=opts)
# build common documentation and compile for different architectures
SConscript('doc/SConscript', variant_dir='build/doc', duplicate=0)
SConscript('src/SConscript', variant_dir='build/x86', duplicate=0)
SConscript('src/SConscript', variant_dir='build/ppc', duplicate=0)
SConscriptChdir(value)
env.SConscriptChdir(value)
By default, scons changes its working directory to the directory in which each subsidiary
SConscript file lives. This behavior may be disabled by specifying either:
SConscriptChdir(0)
env.SConscriptChdir(0)
in which case scons will stay in the top-level directory while reading all SConscript files.
(This may be necessary when building from repositories, when all the directories in which
SConscript files may be found don't necessarily exist locally.) You may enable and disable this
ability by calling SConscriptChdir() multiple times.
Example:
env = Environment()
SConscriptChdir(0)
SConscript('foo/SConscript') # will not chdir to foo
env.SConscriptChdir(1)
SConscript('bar/SConscript') # will chdir to bar
SConsignFile([file, dbm_module])
env.SConsignFile([file, dbm_module])
This tells scons to store all file signatures in the specified database file. If the file name is
omitted, .sconsign is used by default. (The actual file name(s) stored on disk may have an
appropriated suffix appended by the dbm_module.) If file is not an absolute path name, the file
is placed in the same directory as the top-level SConstruct file.
If file is None, then scons will store file signatures in a separate .sconsign file in each
directory, not in one global database file. (This was the default behavior prior to SCons 0.96.91
and 0.97.)
The optional dbm_module argument can be used to specify which Python database module The default
is to use a custom SCons.dblite module that uses pickled Python data structures, and which works
on all Python versions.
Examples:
# Explicitly stores signatures in ".sconsign.dblite"
# in the top-level SConstruct directory (the
# default behavior).
SConsignFile()
# Stores signatures in the file "etc/scons-signatures"
# relative to the top-level SConstruct directory.
SConsignFile("etc/scons-signatures")
# Stores signatures in the specified absolute file name.
SConsignFile("/home/me/SCons/signatures")
# Stores signatures in a separate .sconsign file
# in each directory.
SConsignFile(None)
env.SetDefault(key=val, [...])
Sets construction variables to default values specified with the keyword arguments if (and only
if) the variables are not already set. The following statements are equivalent:
env.SetDefault(FOO = 'foo')
if 'FOO' not in env: env['FOO'] = 'foo'
SetOption(name, value)
env.SetOption(name, value)
This function provides a way to set a select subset of the scons command line options from a
SConscript file. The options supported are:
clean which corresponds to -c, --clean and --remove;
duplicate
which corresponds to --duplicate;
help which corresponds to -h and --help;
implicit_cache
which corresponds to --implicit-cache;
max_drift
which corresponds to --max-drift;
no_exec
which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
num_jobs
which corresponds to -j and --jobs;
random
which corresponds to --random; and
stack_size
which corresponds to --stack-size.
See the documentation for the corresponding command line object for information about each specific
option.
Example:
SetOption('max_drift', 1)
SideEffect(side_effect, target)
env.SideEffect(side_effect, target)
Declares side_effect as a side effect of building target. Both side_effect and target can be a
list, a file name, or a node. A side effect is a target file that is created or updated as a side
effect of building other targets. For example, a Windows PDB file is created as a side effect of
building the .obj files for a static library, and various log files are created updated as side
effects of various TeX commands. If a target is a side effect of multiple build commands, scons
will ensure that only one set of commands is executed at a time. Consequently, you only need to
use this method for side-effect targets that are built as a result of multiple build commands.
Because multiple build commands may update the same side effect file, by default the side_effect
target is not automatically removed when the target is removed by the -c option. (Note, however,
that the side_effect might be removed as part of cleaning the directory in which it lives.) If
you want to make sure the side_effect is cleaned whenever a specific target is cleaned, you must
specify this explicitly with the Clean() or env.Clean() function.
SourceCode(entries, builder)
env.SourceCode(entries, builder)
This function and its associate factory functions are deprecated. There is no replacement. The
intended use was to keep a local tree in sync with an archive, but in actuality the function only
causes the archive to be fetched on the first run. Synchronizing with the archive is best done
external to &SCons;.
Arrange for non-existent source files to be fetched from a source code management system using the
specified builder. The specified entries may be a Node, string or list of both, and may represent
either individual source files or directories in which source files can be found.
For any non-existent source files, scons will search up the directory tree and use the first
SourceCode() builder it finds. The specified builder may be None, in which case scons will not
use a builder to fetch source files for the specified entries, even if a SourceCode() builder has
been specified for a directory higher up the tree.
scons will, by default, fetch files from SCCS or RCS subdirectories without explicit
configuration. This takes some extra processing time to search for the necessary source code
management files on disk. You can avoid these extra searches and speed up your build a little by
disabling these searches as follows:
env.SourceCode('.', None)
Note that if the specified builder is one you create by hand, it must have an associated
construction environment to use when fetching a source file.
scons provides a set of canned factory functions that return appropriate Builders for various
popular source code management systems. Canonical examples of invocation include:
env.SourceCode('.', env.BitKeeper('/usr/local/BKsources'))
env.SourceCode('src', env.CVS('/usr/local/CVSROOT'))
env.SourceCode('/', env.RCS())
env.SourceCode(['f1.c', 'f2.c'], env.SCCS())
env.SourceCode('no_source.c', None)
SourceSignatures(type)
env.SourceSignatures(type)
Note: Although it is not yet officially deprecated, use of this function is discouraged. See the
Decider() function for a more flexible and straightforward way to configure SCons' decision-
making.
The SourceSignatures() function tells scons how to decide if a source file (a file that is not
built from any other files) has changed since the last time it was used to build a particular
target file. Legal values are MD5 or timestamp.
If the environment method is used, the specified type of source signature is only used when
deciding whether targets built with that environment are up-to-date or must be rebuilt. If the
global function is used, the specified type of source signature becomes the default used for all
decisions about whether targets are up-to-date.
MD5 means scons decides that a source file has changed if the MD5 checksum of its contents has
changed since the last time it was used to rebuild a particular target file.
timestamp means scons decides that a source file has changed if its timestamp (modification time)
has changed since the last time it was used to rebuild a particular target file. (Note that
although this is similar to the behavior of Make, by default it will also rebuild if the
dependency is older than the last time it was used to rebuild the target file.)
There is no different between the two behaviors for Python Value() node objects.
MD5 signatures take longer to compute, but are more accurate than timestamp signatures. The
default value is MD5.
Note that the default TargetSignatures() setting (see below) is to use this SourceSignatures()
setting for any target files that are used to build other target files. Consequently, changing
the value of SourceSignatures() will, by default, affect the up-to-date decision for all files in
the build (or all files built with a specific construction environment when env.SourceSignatures()
is used).
Split(arg)
env.Split(arg)
Returns a list of file names or other objects. If arg is a string, it will be split on strings of
white-space characters within the string, making it easier to write long lists of file names. If
arg is already a list, the list will be returned untouched. If arg is any other type of object,
it will be returned as a list containing just the object.
Example:
files = Split("f1.c f2.c f3.c")
files = env.Split("f4.c f5.c f6.c")
files = Split("""
f7.c
f8.c
f9.c
""")
env.subst(input, [raw, target, source, conv])
Performs construction variable interpolation on the specified string or sequence argument input.
By default, leading or trailing white space will be removed from the result. and all sequences of
white space will be compressed to a single space character. Additionally, any $( and $) character
sequences will be stripped from the returned string, The optional raw argument may be set to 1 if
you want to preserve white space and $(-$) sequences. The raw argument may be set to 2 if you
want to strip all characters between any $( and $) pairs (as is done for signature calculation).
If the input is a sequence (list or tuple), the individual elements of the sequence will be
expanded, and the results will be returned as a list.
The optional target and source keyword arguments must be set to lists of target and source nodes,
respectively, if you want the $TARGET, $TARGETS, $SOURCE and $SOURCES to be available for
expansion. This is usually necessary if you are calling env.subst() from within a Python function
used as an SCons action.
Returned string values or sequence elements are converted to their string representation by
default. The optional conv argument may specify a conversion function that will be used in place
of the default. For example, if you want Python objects (including SCons Nodes) to be returned as
Python objects, you can use the Python lambda idiom to pass in an unnamed function that simply
returns its unconverted argument.
Example:
print env.subst("The C compiler is: $CC")
def compile(target, source, env):
sourceDir = env.subst("${SOURCE.srcdir}",
target=target,
source=source)
source_nodes = env.subst('$EXPAND_TO_NODELIST',
conv=lambda x: x)
Tag(node, tags)
Annotates file or directory Nodes with information about how the Package() Builder should package
those files or directories. All tags are optional.
Examples:
# makes sure the built library will be installed with 0644 file
# access mode
Tag( Library( 'lib.c' ), UNIX_ATTR="0644" )
# marks file2.txt to be a documentation file
Tag( 'file2.txt', DOC )
TargetSignatures(type)
env.TargetSignatures(type)
Note: Although it is not yet officially deprecated, use of this function is discouraged. See the
Decider() function for a more flexible and straightforward way to configure SCons' decision-
making.
The TargetSignatures() function tells scons how to decide if a target file (a file that is built
from any other files) has changed since the last time it was used to build some other target file.
Legal values are build; content (or its synonym MD5); timestamp; or source.
If the environment method is used, the specified type of target signature is only used for targets
built with that environment. If the global function is used, the specified type of signature
becomes the default used for all target files that don't have an explicit target signature type
specified for their environments.
content (or its synonym MD5) means scons decides that a target file has changed if the MD5
checksum of its contents has changed since the last time it was used to rebuild some other target
file. This means scons will open up MD5 sum the contents of target files after they're built, and
may decide that it does not need to rebuild "downstream" target files if a file was rebuilt with
exactly the same contents as the last time.
timestamp means scons decides that a target file has changed if its timestamp (modification time)
has changed since the last time it was used to rebuild some other target file. (Note that
although this is similar to the behavior of Make, by default it will also rebuild if the
dependency is older than the last time it was used to rebuild the target file.)
source means scons decides that a target file has changed as specified by the corresponding
SourceSignatures() setting (MD5 or timestamp). This means that scons will treat all input files
to a target the same way, regardless of whether they are source files or have been built from
other files.
build means scons decides that a target file has changed if it has been rebuilt in this invocation
or if its content or timestamp have changed as specified by the corresponding SourceSignatures()
setting. This "propagates" the status of a rebuilt file so that other "downstream" target files
will always be rebuilt, even if the contents or the timestamp have not changed.
build signatures are fastest because content (or MD5) signatures take longer to compute, but are
more accurate than timestamp signatures, and can prevent unnecessary "downstream" rebuilds when a
target file is rebuilt to the exact same contents as the previous build. The source setting
provides the most consistent behavior when other target files may be rebuilt from both source and
target input files. The default value is source.
Because the default setting is source, using SourceSignatures() is generally preferable to
TargetSignatures(), so that the up-to-date decision will be consistent for all files (or all files
built with a specific construction environment). Use of TargetSignatures() provides specific
control for how built target files affect their "downstream" dependencies.
Tool(string, [toolpath, **kw])
env.Tool(string, [toolpath, **kw])
The Tool() form of the function returns a callable object that can be used to initialize a
construction environment using the tools keyword of the Environment() method. The object may be
called with a construction environment as an argument, in which case the object will add the
necessary variables to the construction environment and the name of the tool will be added to the
$TOOLS construction variable.
Additional keyword arguments are passed to the tool's generate() method.
Examples:
env = Environment(tools = [ Tool('msvc') ])
env = Environment()
t = Tool('msvc')
t(env) # adds 'msvc' to the TOOLS variable
u = Tool('opengl', toolpath = ['tools'])
u(env) # adds 'opengl' to the TOOLS variable
The env.Tool() form of the function applies the callable object for the specified tool string to
the environment through which the method was called.
Additional keyword arguments are passed to the tool's generate() method.
env.Tool('gcc')
env.Tool('opengl', toolpath = ['build/tools'])
Value(value, [built_value])
env.Value(value, [built_value])
Returns a Node object representing the specified Python value. Value Nodes can be used as
dependencies of targets. If the result of calling str(value) changes between SCons runs, any
targets depending on Value(value) will be rebuilt. (This is true even when using timestamps to
decide if files are up-to-date.) When using timestamp source signatures, Value Nodes' timestamps
are equal to the system time when the Node is created.
The returned Value Node object has a write() method that can be used to "build" a Value Node by
setting a new value. The optional built_value argument can be specified when the Value Node is
created to indicate the Node should already be considered "built." There is a corresponding
read() method that will return the built value of the Node.
Examples:
env = Environment()
def create(target, source, env):
# A function that will write a 'prefix=$SOURCE'
# string into the file name specified as the
# $TARGET.
f = open(str(target[0]), 'wb')
f.write('prefix=' + source[0].get_contents())
# Fetch the prefix= argument, if any, from the command
# line, and use /usr/local as the default.
prefix = ARGUMENTS.get('prefix', '/usr/local')
# Attach a .Config() builder for the above function action
# to the construction environment.
env['BUILDERS']['Config'] = Builder(action = create)
env.Config(target = 'package-config', source = Value(prefix))
def build_value(target, source, env):
# A function that "builds" a Python Value by updating
# the the Python value with the contents of the file
# specified as the source of the Builder call ($SOURCE).
target[0].write(source[0].get_contents())
output = env.Value('before')
input = env.Value('after')
# Attach a .UpdateValue() builder for the above function
# action to the construction environment.
env['BUILDERS']['UpdateValue'] = Builder(action = build_value)
env.UpdateValue(target = Value(output), source = Value(input))
VariantDir(variant_dir, src_dir, [duplicate])
env.VariantDir(variant_dir, src_dir, [duplicate])
Use the VariantDir() function to create a copy of your sources in another location: if a name
under variant_dir is not found but exists under src_dir, the file or directory is copied to
variant_dir. Target files can be built in a different directory than the original sources by
simply refering to the sources (and targets) within the variant tree.
VariantDir() can be called multiple times with the same src_dir to set up multiple builds with
different options (variants). The src_dir location must be in or underneath the SConstruct file's
directory, and variant_dir may not be underneath src_dir.
The default behavior is for scons to physically duplicate the source files in the variant tree.
Thus, a build performed in the variant tree is guaranteed to be identical to a build performed in
the source tree even if intermediate source files are generated during the build, or preprocessors
or other scanners search for included files relative to the source file, or individual compilers
or other invoked tools are hard-coded to put derived files in the same directory as source files.
If possible on the platform, the duplication is performed by linking rather than copying; see also
the --duplicate command-line option. Moreover, only the files needed for the build are
duplicated; files and directories that are not used are not present in variant_dir.
Duplicating the source tree may be disabled by setting the duplicate argument to 0 (zero). This
will cause scons to invoke Builders using the path names of source files in src_dir and the path
names of derived files within variant_dir. This is always more efficient than duplicate=1, and is
usually safe for most builds (but see above for cases that may cause problems).
Note that VariantDir() works most naturally with a subsidiary SConscript file. However, you would
then call the subsidiary SConscript file not in the source directory, but in the variant_dir,
regardless of the value of duplicate. This is how you tell scons which variant of a source tree
to build:
# run src/SConscript in two variant directories
VariantDir('build/variant1', 'src')
SConscript('build/variant1/SConscript')
VariantDir('build/variant2', 'src')
SConscript('build/variant2/SConscript')
See also the SConscript() function, described above, for another way to specify a variant
directory in conjunction with calling a subsidiary SConscript file.
Examples:
# use names in the build directory, not the source directory
VariantDir('build', 'src', duplicate=0)
Program('build/prog', 'build/source.c')
# this builds both the source and docs in a separate subtree
VariantDir('build', '.', duplicate=0)
SConscript(dirs=['build/src','build/doc'])
# same as previous example, but only uses SConscript
SConscript(dirs='src', variant_dir='build/src', duplicate=0)
SConscript(dirs='doc', variant_dir='build/doc', duplicate=0)
WhereIs(program, [path, pathext, reject])
env.WhereIs(program, [path, pathext, reject])
Searches for the specified executable program, returning the full path name to the program if it
is found, and returning None if not. Searches the specified path, the value of the calling
environment's PATH (env['ENV']['PATH']), or the user's current external PATH (os.environ['PATH'])
by default. On Windows systems, searches for executable programs with any of the file extensions
listed in the specified pathext, the calling environment's PATHEXT (env['ENV']['PATHEXT']) or the
user's current PATHEXT (os.environ['PATHEXT']) by default. Will not select any path name or names
in the specified reject list, if any.
SConscript Variables
In addition to the global functions and methods, scons supports a number of Python variables that can be
used in SConscript files to affect how you want the build to be performed. These variables may be
accessed from custom Python modules that you import into an SConscript file by adding the following to
the Python module:
from SCons.Script import *
ARGLIST
A list keyword=value arguments specified on the command line. Each element in the list is a tuple
containing the (keyword,value) of the argument. The separate keyword and value elements of the
tuple can be accessed by subscripting for element [0] and [1] of the tuple, respectively.
Example:
print "first keyword, value =", ARGLIST[0][0], ARGLIST[0][1]
print "second keyword, value =", ARGLIST[1][0], ARGLIST[1][1]
third_tuple = ARGLIST[2]
print "third keyword, value =", third_tuple[0], third_tuple[1]
for key, value in ARGLIST:
# process key and value
ARGUMENTS
A dictionary of all the keyword=value arguments specified on the command line. The dictionary is
not in order, and if a given keyword has more than one value assigned to it on the command line,
the last (right-most) value is the one in the ARGUMENTS dictionary.
Example:
if ARGUMENTS.get('debug', 0):
env = Environment(CCFLAGS = '-g')
else:
env = Environment()
BUILD_TARGETS
A list of the targets which scons will actually try to build, regardless of whether they were
specified on the command line or via the Default() function or method. The elements of this list
may be strings or nodes, so you should run the list through the Python str function to make sure
any Node path names are converted to strings.
Because this list may be taken from the list of targets specified using the Default() function or
method, the contents of the list may change on each successive call to Default(). See the
DEFAULT_TARGETS list, below, for additional information.
Example:
if 'foo' in BUILD_TARGETS:
print "Don't forget to test the `foo' program!"
if 'special/program' in BUILD_TARGETS:
SConscript('special')
Note that the BUILD_TARGETS list only contains targets expected listed on the command line or via
calls to the Default() function or method. It does not contain all dependent targets that will be
built as a result of making the sure the explicitly-specified targets are up to date.
COMMAND_LINE_TARGETS
A list of the targets explicitly specified on the command line. If there are no targets specified
on the command line, the list is empty. This can be used, for example, to take specific actions
only when a certain target or targets is explicitly being built.
Example:
if 'foo' in COMMAND_LINE_TARGETS:
print "Don't forget to test the `foo' program!"
if 'special/program' in COMMAND_LINE_TARGETS:
SConscript('special')
DEFAULT_TARGETS
A list of the target nodes that have been specified using the Default() function or method. The
elements of the list are nodes, so you need to run them through the Python str function to get at
the path name for each Node.
Example:
print str(DEFAULT_TARGETS[0])
if 'foo' in map(str, DEFAULT_TARGETS):
print "Don't forget to test the `foo' program!"
The contents of the DEFAULT_TARGETS list change on on each successive call to the Default()
function:
print map(str, DEFAULT_TARGETS) # originally []
Default('foo')
print map(str, DEFAULT_TARGETS) # now a node ['foo']
Default('bar')
print map(str, DEFAULT_TARGETS) # now a node ['foo', 'bar']
Default(None)
print map(str, DEFAULT_TARGETS) # back to []
Consequently, be sure to use DEFAULT_TARGETS only after you've made all of your Default() calls,
or else simply be careful of the order of these statements in your SConscript files so that you
don't look for a specific default target before it's actually been added to the list.
Construction Variables
A construction environment has an associated dictionary of construction variables that are used by built-
in or user-supplied build rules. Construction variables must follow the same rules for Python
identifiers: the initial character must be an underscore or letter, followed by any number of
underscores, letters, or digits.
A number of useful construction variables are automatically defined by scons for each supported platform,
and additional construction variables can be defined by the user. The following is a list of the
automatically defined construction variables:
AR The static library archiver.
ARCHITECTURE
Specifies the system architecture for which the package is being built. The default is the system
architecture of the machine on which SCons is running. This is used to fill in the Architecture:
field in an Ipkg control file, and as part of the name of a generated RPM file.
ARCOM The command line used to generate a static library from object files.
ARCOMSTR
The string displayed when an object file is generated from an assembly-language source file. If
this is not set, then $ARCOM (the command line) is displayed.
env = Environment(ARCOMSTR = "Archiving $TARGET")
ARFLAGS
General options passed to the static library archiver.
AS The assembler.
ASCOM The command line used to generate an object file from an assembly-language source file.
ASCOMSTR
The string displayed when an object file is generated from an assembly-language source file. If
this is not set, then $ASCOM (the command line) is displayed.
env = Environment(ASCOMSTR = "Assembling $TARGET")
ASFLAGS
General options passed to the assembler.
ASPPCOM
The command line used to assemble an assembly-language source file into an object file after first
running the file through the C preprocessor. Any options specified in the $ASFLAGS and $CPPFLAGS
construction variables are included on this command line.
ASPPCOMSTR
The string displayed when an object file is generated from an assembly-language source file after
first running the file through the C preprocessor. If this is not set, then $ASPPCOM (the command
line) is displayed.
env = Environment(ASPPCOMSTR = "Assembling $TARGET")
ASPPFLAGS
General options when an assembling an assembly-language source file into an object file after
first running the file through the C preprocessor. The default is to use the value of $ASFLAGS.
BIBTEX The bibliography generator for the TeX formatter and typesetter and the LaTeX structured formatter
and typesetter.
BIBTEXCOM
The command line used to call the bibliography generator for the TeX formatter and typesetter and
the LaTeX structured formatter and typesetter.
BIBTEXCOMSTR
The string displayed when generating a bibliography for TeX or LaTeX. If this is not set, then
$BIBTEXCOM (the command line) is displayed.
env = Environment(BIBTEXCOMSTR = "Generating bibliography $TARGET")
BIBTEXFLAGS
General options passed to the bibliography generator for the TeX formatter and typesetter and the
LaTeX structured formatter and typesetter.
BITKEEPER
The BitKeeper executable.
BITKEEPERCOM
The command line for fetching source files using BitKeeper.
BITKEEPERCOMSTR
The string displayed when fetching a source file using BitKeeper. If this is not set, then
$BITKEEPERCOM (the command line) is displayed.
BITKEEPERGET
The command ($BITKEEPER) and subcommand for fetching source files using BitKeeper.
BITKEEPERGETFLAGS
Options that are passed to the BitKeeper get subcommand.
BUILDERS
A dictionary mapping the names of the builders available through this environment to underlying
Builder objects. Builders named Alias, CFile, CXXFile, DVI, Library, Object, PDF, PostScript, and
Program are available by default. If you initialize this variable when an Environment is created:
env = Environment(BUILDERS = {'NewBuilder' : foo})
the default Builders will no longer be available. To use a new Builder object in addition to the
default Builders, add your new Builder object like this:
env = Environment()
env.Append(BUILDERS = {'NewBuilder' : foo})
or this:
env = Environment()
env['BUILDERS]['NewBuilder'] = foo
CC The C compiler.
CCCOM The command line used to compile a C source file to a (static) object file. Any options specified
in the $CFLAGS, $CCFLAGS and $CPPFLAGS construction variables are included on this command line.
CCCOMSTR
The string displayed when a C source file is compiled to a (static) object file. If this is not
set, then $CCCOM (the command line) is displayed.
env = Environment(CCCOMSTR = "Compiling static object $TARGET")
CCFLAGS
General options that are passed to the C and C++ compilers.
CCPCHFLAGS
Options added to the compiler command line to support building with precompiled headers. The
default value expands expands to the appropriate Microsoft Visual C++ command-line options when
the $PCH construction variable is set.
CCPDBFLAGS
Options added to the compiler command line to support storing debugging information in a Microsoft
Visual C++ PDB file. The default value expands expands to appropriate Microsoft Visual C++
command-line options when the $PDB construction variable is set.
The Visual C++ compiler option that SCons uses by default to generate PDB information is /Z7.
This works correctly with parallel (-j) builds because it embeds the debug information in the
intermediate object files, as opposed to sharing a single PDB file between multiple object files.
This is also the only way to get debug information embedded into a static library. Using the /Zi
instead may yield improved link-time performance, although parallel builds will no longer work.
You can generate PDB files with the /Zi switch by overriding the default $CCPDBFLAGS variable as
follows:
env['CCPDBFLAGS'] = ['${(PDB and "/Zi /Fd%s" % File(PDB)) or ""}']
An alternative would be to use the /Zi to put the debugging information in a separate .pdb file
for each object file by overriding the $CCPDBFLAGS variable as follows:
env['CCPDBFLAGS'] = '/Zi /Fd${TARGET}.pdb'
CCVERSION
The version number of the C compiler. This may or may not be set, depending on the specific C
compiler being used.
CFILESUFFIX
The suffix for C source files. This is used by the internal CFile builder when generating C files
from Lex (.l) or YACC (.y) input files. The default suffix, of course, is .c (lower case). On
case-insensitive systems (like Windows), SCons also treats .C (upper case) files as C files.
CFLAGS General options that are passed to the C compiler (C only; not C++).
CHANGE_SPECFILE
A hook for modifying the file that controls the packaging build (the .spec for RPM, the control
for Ipkg, the .wxs for MSI). If set, the function will be called after the SCons template for the
file has been written. XXX
CHANGED_SOURCES
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
CHANGED_TARGETS
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
CHANGELOG
The name of a file containing the change log text to be included in the package. This is included
as the %changelog section of the RPM .spec file.
_concat
A function used to produce variables like $_CPPINCFLAGS. It takes four or five arguments: a prefix
to concatenate onto each element, a list of elements, a suffix to concatenate onto each element,
an environment for variable interpolation, and an optional function that will be called to
transform the list before concatenation.
env['_CPPINCFLAGS'] = '$( ${_concat(INCPREFIX, CPPPATH, INCSUFFIX, __env__, RDirs)} $)',
CONFIGUREDIR
The name of the directory in which Configure context test files are written. The default is
.sconf_temp in the top-level directory containing the SConstruct file.
CONFIGURELOG
The name of the Configure context log file. The default is config.log in the top-level directory
containing the SConstruct file.
_CPPDEFFLAGS
An automatically-generated construction variable containing the C preprocessor command-line
options to define values. The value of $_CPPDEFFLAGS is created by appending $CPPDEFPREFIX and
$CPPDEFSUFFIX to the beginning and end of each definition in $CPPDEFINES.
CPPDEFINES
A platform independent specification of C preprocessor definitions. The definitions will be added
to command lines through the automatically-generated $_CPPDEFFLAGS construction variable (see
above), which is constructed according to the type of value of $CPPDEFINES:
If $CPPDEFINES is a string, the values of the $CPPDEFPREFIXand$CPPDEFSUFFIX construction variables
will be added to the beginning and end.
# Will add -Dxyz to POSIX compiler command lines,
# and /Dxyz to Microsoft Visual C++ command lines.
env = Environment(CPPDEFINES='xyz')
If $CPPDEFINES is a list, the values of the $CPPDEFPREFIXand$CPPDEFSUFFIX construction variables
will be appended to the beginning and end of each element in the list. If any element is a list
or tuple, then the first item is the name being defined and the second item is its value:
# Will add -DB=2 -DA to POSIX compiler command lines,
# and /DB=2 /DA to Microsoft Visual C++ command lines.
env = Environment(CPPDEFINES=[('B', 2), 'A'])
If $CPPDEFINES is a dictionary, the values of the $CPPDEFPREFIXand$CPPDEFSUFFIX construction
variables will be appended to the beginning and end of each item from the dictionary. The key of
each dictionary item is a name being defined to the dictionary item's corresponding value; if the
value is None, then the name is defined without an explicit value. Note that the resulting flags
are sorted by keyword to ensure that the order of the options on the command line is consistent
each time scons is run.
# Will add -DA -DB=2 to POSIX compiler command lines,
# and /DA /DB=2 to Microsoft Visual C++ command lines.
env = Environment(CPPDEFINES={'B':2, 'A':None})
CPPDEFPREFIX
The prefix used to specify preprocessor definitions on the C compiler command line. This will be
appended to the beginning of each definition in the $CPPDEFINES construction variable when the
$_CPPDEFFLAGS variable is automatically generated.
CPPDEFSUFFIX
The suffix used to specify preprocessor definitions on the C compiler command line. This will be
appended to the end of each definition in the $CPPDEFINES construction variable when the
$_CPPDEFFLAGS variable is automatically generated.
CPPFLAGS
User-specified C preprocessor options. These will be included in any command that uses the C
preprocessor, including not just compilation of C and C++ source files via the $CCCOM, $SHCCCOM,
$CXXCOM and $SHCXXCOM command lines, but also the $FORTRANPPCOM, $SHFORTRANPPCOM, $F77PPCOM and
$SHF77PPCOM command lines used to compile a Fortran source file, and the $ASPPCOM command line
used to assemble an assembly language source file, after first running each file through the C
preprocessor. Note that this variable does not contain -I (or similar) include search path
options that scons generates automatically from $CPPPATH. See $_CPPINCFLAGS, below, for the
variable that expands to those options.
_CPPINCFLAGS
An automatically-generated construction variable containing the C preprocessor command-line
options for specifying directories to be searched for include files. The value of $_CPPINCFLAGS
is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in
$CPPPATH.
CPPPATH
The list of directories that the C preprocessor will search for include directories. The C/C++
implicit dependency scanner will search these directories for include files. Don't explicitly put
include directory arguments in CCFLAGS or CXXFLAGS because the result will be non-portable and the
directories will not be searched by the dependency scanner. Note: directory names in CPPPATH will
be looked-up relative to the SConscript directory when they are used in a command. To force scons
to look-up a directory relative to the root of the source tree use #:
env = Environment(CPPPATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(CPPPATH=include)
The directory list will be added to command lines through the automatically-generated
$_CPPINCFLAGS construction variable, which is constructed by appending the values of the
$INCPREFIXand$INCSUFFIX construction variables to the beginning and end of each directory in
$CPPPATH. Any command lines you define that need the CPPPATH directory list should include
$_CPPINCFLAGS:
env = Environment(CCCOM="my_compiler $_CPPINCFLAGS -c -o $TARGET $SOURCE")
CPPSUFFIXES
The list of suffixes of files that will be scanned for C preprocessor implicit dependencies
(#include lines). The default list is:
[".c", ".C", ".cxx", ".cpp", ".c++", ".cc",
".h", ".H", ".hxx", ".hpp", ".hh",
".F", ".fpp", ".FPP",
".m", ".mm",
".S", ".spp", ".SPP"]
CVS The CVS executable.
CVSCOFLAGS
Options that are passed to the CVS checkout subcommand.
CVSCOM The command line used to fetch source files from a CVS repository.
CVSCOMSTR
The string displayed when fetching a source file from a CVS repository. If this is not set, then
$CVSCOM (the command line) is displayed.
CVSFLAGS
General options that are passed to CVS. By default, this is set to -d $CVSREPOSITORY to specify
from where the files must be fetched.
CVSREPOSITORY
The path to the CVS repository. This is referenced in the default $CVSFLAGS value.
CXX The C++ compiler.
CXXCOM The command line used to compile a C++ source file to an object file. Any options specified in
the $CXXFLAGS and $CPPFLAGS construction variables are included on this command line.
CXXCOMSTR
The string displayed when a C++ source file is compiled to a (static) object file. If this is not
set, then $CXXCOM (the command line) is displayed.
env = Environment(CXXCOMSTR = "Compiling static object $TARGET")
CXXFILESUFFIX
The suffix for C++ source files. This is used by the internal CXXFile builder when generating C++
files from Lex (.ll) or YACC (.yy) input files. The default suffix is .cc. SCons also treats
files with the suffixes .cpp, .cxx, .c++, and .C++ as C++ files, and files with .mm suffixes as
Objective C++ files. On case-sensitive systems (Linux, UNIX, and other POSIX-alikes), SCons also
treats .C (upper case) files as C++ files.
CXXFLAGS
General options that are passed to the C++ compiler. By default, this includes the value of
$CCFLAGS, so that setting $CCFLAGS affects both C and C++ compilation. If you want to add
C++-specific flags, you must set or override the value of $CXXFLAGS.
CXXVERSION
The version number of the C++ compiler. This may or may not be set, depending on the specific C++
compiler being used.
DESCRIPTION
A long description of the project being packaged. This is included in the relevant section of the
file that controls the packaging build.
DESCRIPTION_lang
A language-specific long description for the specified lang. This is used to populate a
%description -l section of an RPM .spec file.
Dir A function that converts a string into a Dir instance relative to the target being built.
Dirs A function that converts a list of strings into a list of Dir instances relative to the target
being built.
DSUFFIXES
The list of suffixes of files that will be scanned for imported D package files. The default list
is:
['.d']
DVIPDF The TeX DVI file to PDF file converter.
DVIPDFCOM
The command line used to convert TeX DVI files into a PDF file.
DVIPDFCOMSTR
The string displayed when a TeX DVI file is converted into a PDF file. If this is not set, then
$DVIPDFCOM (the command line) is displayed.
DVIPDFFLAGS
General options passed to the TeX DVI file to PDF file converter.
DVIPS The TeX DVI file to PostScript converter.
DVIPSFLAGS
General options passed to the TeX DVI file to PostScript converter.
ENV A dictionary of environment variables to use when invoking commands. When $ENV is used in a
command all list values will be joined using the path separator and any other non-string values
will simply be coerced to a string. Note that, by default, scons does not propagate the
environment in force when you execute scons to the commands used to build target files. This is
so that builds will be guaranteed repeatable regardless of the environment variables set at the
time scons is invoked.
If you want to propagate your environment variables to the commands executed to build target
files, you must do so explicitly:
import os
env = Environment(ENV = os.environ)
Note that you can choose only to propagate certain environment variables. A common example is the
system PATH environment variable, so that scons uses the same utilities as the invoking shell (or
other process):
import os
env = Environment(ENV = {'PATH' : os.environ['PATH']})
ESCAPE A function that will be called to escape shell special characters in command lines. The function
should take one argument: the command line string to escape; and should return the escaped command
line.
F77 The Fortran 77 compiler. You should normally set the $FORTRAN variable, which specifies the
default Fortran compiler for all Fortran versions. You only need to set $F77 if you need to use a
specific compiler or compiler version for Fortran 77 files.
F77COM The command line used to compile a Fortran 77 source file to an object file. You only need to set
$F77COM if you need to use a specific command line for Fortran 77 files. You should normally set
the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.
F77COMSTR
The string displayed when a Fortran 77 source file is compiled to an object file. If this is not
set, then $F77COM or $FORTRANCOM (the command line) is displayed.
F77FILESUFFIXES
The list of file extensions for which the F77 dialect will be used. By default, this is ['.f77']
F77FLAGS
General user-specified options that are passed to the Fortran 77 compiler. Note that this
variable does not contain -I (or similar) include search path options that scons generates
automatically from $F77PATH. See $_F77INCFLAGS below, for the variable that expands to those
options. You only need to set $F77FLAGS if you need to define specific user options for Fortran
77 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified
options passed to the default Fortran compiler for all Fortran versions.
_F77INCFLAGS
An automatically-generated construction variable containing the Fortran 77 compiler command-line
options for specifying directories to be searched for include files. The value of $_F77INCFLAGS
is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in
$F77PATH.
F77PATH
The list of directories that the Fortran 77 compiler will search for include directories. The
implicit dependency scanner will search these directories for include files. Don't explicitly put
include directory arguments in $F77FLAGS because the result will be non-portable and the
directories will not be searched by the dependency scanner. Note: directory names in $F77PATH will
be looked-up relative to the SConscript directory when they are used in a command. To force scons
to look-up a directory relative to the root of the source tree use #: You only need to set
$F77PATH if you need to define a specific include path for Fortran 77 files. You should normally
set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler
for all Fortran versions.
env = Environment(F77PATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(F77PATH=include)
The directory list will be added to command lines through the automatically-generated
$_F77INCFLAGS construction variable, which is constructed by appending the values of the
$INCPREFIXand$INCSUFFIX construction variables to the beginning and end of each directory in
$F77PATH. Any command lines you define that need the F77PATH directory list should include
$_F77INCFLAGS:
env = Environment(F77COM="my_compiler $_F77INCFLAGS -c -o $TARGET $SOURCE")
F77PPCOM
The command line used to compile a Fortran 77 source file to an object file after first running
the file through the C preprocessor. Any options specified in the $F77FLAGS and $CPPFLAGS
construction variables are included on this command line. You only need to set $F77PPCOM if you
need to use a specific C-preprocessor command line for Fortran 77 files. You should normally set
the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all
Fortran versions.
F77PPCOMSTR
The string displayed when a Fortran 77 source file is compiled to an object file after first
running the file through the C preprocessor. If this is not set, then $F77PPCOM or $FORTRANPPCOM
(the command line) is displayed.
F77PPFILESUFFIXES
The list of file extensions for which the compilation + preprocessor pass for F77 dialect will be
used. By default, this is empty
F90 The Fortran 90 compiler. You should normally set the $FORTRAN variable, which specifies the
default Fortran compiler for all Fortran versions. You only need to set $F90 if you need to use a
specific compiler or compiler version for Fortran 90 files.
F90COM The command line used to compile a Fortran 90 source file to an object file. You only need to set
$F90COM if you need to use a specific command line for Fortran 90 files. You should normally set
the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.
F90COMSTR
The string displayed when a Fortran 90 source file is compiled to an object file. If this is not
set, then $F90COM or $FORTRANCOM (the command line) is displayed.
F90FILESUFFIXES
The list of file extensions for which the F90 dialect will be used. By default, this is ['.f90']
F90FLAGS
General user-specified options that are passed to the Fortran 90 compiler. Note that this
variable does not contain -I (or similar) include search path options that scons generates
automatically from $F90PATH. See $_F90INCFLAGS below, for the variable that expands to those
options. You only need to set $F90FLAGS if you need to define specific user options for Fortran
90 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified
options passed to the default Fortran compiler for all Fortran versions.
_F90INCFLAGS
An automatically-generated construction variable containing the Fortran 90 compiler command-line
options for specifying directories to be searched for include files. The value of $_F90INCFLAGS
is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in
$F90PATH.
F90PATH
The list of directories that the Fortran 90 compiler will search for include directories. The
implicit dependency scanner will search these directories for include files. Don't explicitly put
include directory arguments in $F90FLAGS because the result will be non-portable and the
directories will not be searched by the dependency scanner. Note: directory names in $F90PATH will
be looked-up relative to the SConscript directory when they are used in a command. To force scons
to look-up a directory relative to the root of the source tree use #: You only need to set
$F90PATH if you need to define a specific include path for Fortran 90 files. You should normally
set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler
for all Fortran versions.
env = Environment(F90PATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(F90PATH=include)
The directory list will be added to command lines through the automatically-generated
$_F90INCFLAGS construction variable, which is constructed by appending the values of the
$INCPREFIXand$INCSUFFIX construction variables to the beginning and end of each directory in
$F90PATH. Any command lines you define that need the F90PATH directory list should include
$_F90INCFLAGS:
env = Environment(F90COM="my_compiler $_F90INCFLAGS -c -o $TARGET $SOURCE")
F90PPCOM
The command line used to compile a Fortran 90 source file to an object file after first running
the file through the C preprocessor. Any options specified in the $F90FLAGS and $CPPFLAGS
construction variables are included on this command line. You only need to set $F90PPCOM if you
need to use a specific C-preprocessor command line for Fortran 90 files. You should normally set
the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all
Fortran versions.
F90PPCOMSTR
The string displayed when a Fortran 90 source file is compiled after first running the file
through the C preprocessor. If this is not set, then $F90PPCOM or $FORTRANPPCOM (the command
line) is displayed.
F90PPFILESUFFIXES
The list of file extensions for which the compilation + preprocessor pass for F90 dialect will be
used. By default, this is empty
F95 The Fortran 95 compiler. You should normally set the $FORTRAN variable, which specifies the
default Fortran compiler for all Fortran versions. You only need to set $F95 if you need to use a
specific compiler or compiler version for Fortran 95 files.
F95COM The command line used to compile a Fortran 95 source file to an object file. You only need to set
$F95COM if you need to use a specific command line for Fortran 95 files. You should normally set
the $FORTRANCOM variable, which specifies the default command line for all Fortran versions.
F95COMSTR
The string displayed when a Fortran 95 source file is compiled to an object file. If this is not
set, then $F95COM or $FORTRANCOM (the command line) is displayed.
F95FILESUFFIXES
The list of file extensions for which the F95 dialect will be used. By default, this is ['.f95']
F95FLAGS
General user-specified options that are passed to the Fortran 95 compiler. Note that this
variable does not contain -I (or similar) include search path options that scons generates
automatically from $F95PATH. See $_F95INCFLAGS below, for the variable that expands to those
options. You only need to set $F95FLAGS if you need to define specific user options for Fortran
95 files. You should normally set the $FORTRANFLAGS variable, which specifies the user-specified
options passed to the default Fortran compiler for all Fortran versions.
_F95INCFLAGS
An automatically-generated construction variable containing the Fortran 95 compiler command-line
options for specifying directories to be searched for include files. The value of $_F95INCFLAGS
is created by appending $INCPREFIX and $INCSUFFIX to the beginning and end of each directory in
$F95PATH.
F95PATH
The list of directories that the Fortran 95 compiler will search for include directories. The
implicit dependency scanner will search these directories for include files. Don't explicitly put
include directory arguments in $F95FLAGS because the result will be non-portable and the
directories will not be searched by the dependency scanner. Note: directory names in $F95PATH will
be looked-up relative to the SConscript directory when they are used in a command. To force scons
to look-up a directory relative to the root of the source tree use #: You only need to set
$F95PATH if you need to define a specific include path for Fortran 95 files. You should normally
set the $FORTRANPATH variable, which specifies the include path for the default Fortran compiler
for all Fortran versions.
env = Environment(F95PATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(F95PATH=include)
The directory list will be added to command lines through the automatically-generated
$_F95INCFLAGS construction variable, which is constructed by appending the values of the
$INCPREFIXand$INCSUFFIX construction variables to the beginning and end of each directory in
$F95PATH. Any command lines you define that need the F95PATH directory list should include
$_F95INCFLAGS:
env = Environment(F95COM="my_compiler $_F95INCFLAGS -c -o $TARGET $SOURCE")
F95PPCOM
The command line used to compile a Fortran 95 source file to an object file after first running
the file through the C preprocessor. Any options specified in the $F95FLAGS and $CPPFLAGS
construction variables are included on this command line. You only need to set $F95PPCOM if you
need to use a specific C-preprocessor command line for Fortran 95 files. You should normally set
the $FORTRANPPCOM variable, which specifies the default C-preprocessor command line for all
Fortran versions.
F95PPCOMSTR
The string displayed when a Fortran 95 source file is compiled to an object file after first
running the file through the C preprocessor. If this is not set, then $F95PPCOM or $FORTRANPPCOM
(the command line) is displayed.
F95PPFILESUFFIXES
The list of file extensions for which the compilation + preprocessor pass for F95 dialect will be
used. By default, this is empty
File A function that converts a string into a File instance relative to the target being built.
FORTRAN
The default Fortran compiler for all versions of Fortran.
FORTRANCOM
The command line used to compile a Fortran source file to an object file. By default, any options
specified in the $FORTRANFLAGS, $CPPFLAGS, $_CPPDEFFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS
construction variables are included on this command line.
FORTRANCOMSTR
The string displayed when a Fortran source file is compiled to an object file. If this is not
set, then $FORTRANCOM (the command line) is displayed.
FORTRANFILESUFFIXES
The list of file extensions for which the FORTRAN dialect will be used. By default, this is ['.f',
'.for', '.ftn']
FORTRANFLAGS
General user-specified options that are passed to the Fortran compiler. Note that this variable
does not contain -I (or similar) include or module search path options that scons generates
automatically from $FORTRANPATH. See $_FORTRANINCFLAGSand$_FORTRANMODFLAG, below, for the
variables that expand those options.
_FORTRANINCFLAGS
An automatically-generated construction variable containing the Fortran compiler command-line
options for specifying directories to be searched for include files and module files. The value
of $_FORTRANINCFLAGS is created by prepending/appending $INCPREFIX and $INCSUFFIX to the beginning
and end of each directory in $FORTRANPATH.
FORTRANMODDIR
Directory location where the Fortran compiler should place any module files it generates. This
variable is empty, by default. Some Fortran compilers will internally append this directory in the
search path for module files, as well.
FORTRANMODDIRPREFIX
The prefix used to specify a module directory on the Fortran compiler command line. This will be
appended to the beginning of the directory in the $FORTRANMODDIR construction variables when the
$_FORTRANMODFLAG variables is automatically generated.
FORTRANMODDIRSUFFIX
The suffix used to specify a module directory on the Fortran compiler command line. This will be
appended to the beginning of the directory in the $FORTRANMODDIR construction variables when the
$_FORTRANMODFLAG variables is automatically generated.
_FORTRANMODFLAG
An automatically-generated construction variable containing the Fortran compiler command-line
option for specifying the directory location where the Fortran compiler should place any module
files that happen to get generated during compilation. The value of $_FORTRANMODFLAG is created
by prepending/appending $FORTRANMODDIRPREFIX and $FORTRANMODDIRSUFFIX to the beginning and end of
the directory in $FORTRANMODDIR.
FORTRANMODPREFIX
The module file prefix used by the Fortran compiler. SCons assumes that the Fortran compiler
follows the quasi-standard naming convention for module files of module_name.mod. As a result,
this variable is left empty, by default. For situations in which the compiler does not
necessarily follow the normal convention, the user may use this variable. Its value will be
appended to every module file name as scons attempts to resolve dependencies.
FORTRANMODSUFFIX
The module file suffix used by the Fortran compiler. SCons assumes that the Fortran compiler
follows the quasi-standard naming convention for module files of module_name.mod. As a result,
this variable is set to ".mod", by default. For situations in which the compiler does not
necessarily follow the normal convention, the user may use this variable. Its value will be
appended to every module file name as scons attempts to resolve dependencies.
FORTRANPATH
The list of directories that the Fortran compiler will search for include files and (for some
compilers) module files. The Fortran implicit dependency scanner will search these directories for
include files (but not module files since they are autogenerated and, as such, may not actually
exist at the time the scan takes place). Don't explicitly put include directory arguments in
FORTRANFLAGS because the result will be non-portable and the directories will not be searched by
the dependency scanner. Note: directory names in FORTRANPATH will be looked-up relative to the
SConscript directory when they are used in a command. To force scons to look-up a directory
relative to the root of the source tree use #:
env = Environment(FORTRANPATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(FORTRANPATH=include)
The directory list will be added to command lines through the automatically-generated
$_FORTRANINCFLAGS construction variable, which is constructed by appending the values of the
$INCPREFIXand$INCSUFFIX construction variables to the beginning and end of each directory in
$FORTRANPATH. Any command lines you define that need the FORTRANPATH directory list should
include $_FORTRANINCFLAGS:
env = Environment(FORTRANCOM="my_compiler $_FORTRANINCFLAGS -c -o $TARGET $SOURCE")
FORTRANPPCOM
The command line used to compile a Fortran source file to an object file after first running the
file through the C preprocessor. By default, any options specified in the $FORTRANFLAGS,
$CPPFLAGS, $_CPPDEFFLAGS, $_FORTRANMODFLAG, and $_FORTRANINCFLAGS construction variables are
included on this command line.
FORTRANPPCOMSTR
The string displayed when a Fortran source file is compiled to an object file after first running
the file through the C preprocessor. If this is not set, then $FORTRANPPCOM (the command line) is
displayed.
FORTRANPPFILESUFFIXES
The list of file extensions for which the compilation + preprocessor pass for FORTRAN dialect will
be used. By default, this is ['.fpp', '.FPP']
FORTRANSUFFIXES
The list of suffixes of files that will be scanned for Fortran implicit dependencies (INCLUDE
lines and USE statements). The default list is:
[".f", ".F", ".for", ".FOR", ".ftn", ".FTN", ".fpp", ".FPP",
".f77", ".F77", ".f90", ".F90", ".f95", ".F95"]
FRAMEWORKPATH
On Mac OS X with gcc, a list containing the paths to search for frameworks. Used by the compiler
to find framework-style includes like #include <Fmwk/Header.h>. Used by the linker to find user-
specified frameworks when linking (see $FRAMEWORKS). For example:
env.AppendUnique(FRAMEWORKPATH='#myframeworkdir')
will add
... -Fmyframeworkdir
to the compiler and linker command lines.
_FRAMEWORKPATH
On Mac OS X with gcc, an automatically-generated construction variable containing the linker
command-line options corresponding to $FRAMEWORKPATH.
FRAMEWORKPATHPREFIX
On Mac OS X with gcc, the prefix to be used for the FRAMEWORKPATH entries. (see $FRAMEWORKPATH).
The default value is -F.
FRAMEWORKPREFIX
On Mac OS X with gcc, the prefix to be used for linking in frameworks (see $FRAMEWORKS). The
default value is -framework.
_FRAMEWORKS
On Mac OS X with gcc, an automatically-generated construction variable containing the linker
command-line options for linking with FRAMEWORKS.
FRAMEWORKS
On Mac OS X with gcc, a list of the framework names to be linked into a program or shared library
or bundle. The default value is the empty list. For example:
env.AppendUnique(FRAMEWORKS=Split('System Cocoa SystemConfiguration'))
FRAMEWORKSFLAGS
On Mac OS X with gcc, general user-supplied frameworks options to be added at the end of a command
line building a loadable module. (This has been largely superseded by the $FRAMEWORKPATH,
$FRAMEWORKPATHPREFIX, $FRAMEWORKPREFIX and $FRAMEWORKS variables described above.)
GS The Ghostscript program used to convert PostScript to PDF files.
GSCOM The Ghostscript command line used to convert PostScript to PDF files.
GSCOMSTR
The string displayed when Ghostscript is used to convert a PostScript file to a PDF file. If this
is not set, then $GSCOM (the command line) is displayed.
GSFLAGS
General options passed to the Ghostscript program when converting PostScript to PDF files.
HOST_ARCH
Sets the host architecture for Visual Studio compiler. If not set, default to the detected host
architecture: note that this may depend on the python you are using. This variable must be passed
as an argument to the Environment() constructor; setting it later has no effect.
Valid values are the same as for $TARGET_ARCH.
This is currently only used on Windows, but in the future it will be used on other OSes as well.
HOST_OS
The name of the host operating system used to create the Environment.
If a platform is specified when creating the Environment, then
that Platform's logic will handle setting this value.
This value is immutable, and should not be changed by the user after
the Environment is initialized.
Currently only set for Win32.
IDLSUFFIXES
The list of suffixes of files that will be scanned for IDL implicit dependencies (#include or
import lines). The default list is:
[".idl", ".IDL"]
IMPLICIT_COMMAND_DEPENDENCIES
Controls whether or not SCons will add implicit dependencies for the commands executed to build
targets.
By default, SCons will add to each target an implicit dependency on the command represented by the
first argument on any command line it executes. The specific file for the dependency is found by
searching the PATH variable in the ENV environment used to execute the command.
If the construction variable $IMPLICIT_COMMAND_DEPENDENCIES is set to a false value (None, False,
0, etc.), then the implicit dependency will not be added to the targets built with that
construction environment.
env = Environment(IMPLICIT_COMMAND_DEPENDENCIES = 0)
INCPREFIX
The prefix used to specify an include directory on the C compiler command line. This will be
appended to the beginning of each directory in the $CPPPATH and $FORTRANPATH construction
variables when the $_CPPINCFLAGS and $_FORTRANINCFLAGS variables are automatically generated.
INCSUFFIX
The suffix used to specify an include directory on the C compiler command line. This will be
appended to the end of each directory in the $CPPPATH and $FORTRANPATH construction variables when
the $_CPPINCFLAGS and $_FORTRANINCFLAGS variables are automatically generated.
INSTALL
A function to be called to install a file into a destination file name. The default function
copies the file into the destination (and sets the destination file's mode and permission bits to
match the source file's). The function takes the following arguments:
def install(dest, source, env):
dest is the path name of the destination file. source is the path name of the source file. env
is the construction environment (a dictionary of construction values) in force for this file
installation.
INSTALLSTR
The string displayed when a file is installed into a destination file name. The default is:
Install file: "$SOURCE" as "$TARGET"
INTEL_C_COMPILER_VERSION
Set by the "intelc" Tool to the major version number of the Intel C compiler selected for use.
JAR The Java archive tool.
JARCHDIR
The directory to which the Java archive tool should change (using the -C option).
JARCOM The command line used to call the Java archive tool.
JARCOMSTR
The string displayed when the Java archive tool is called If this is not set, then $JARCOM (the
command line) is displayed.
env = Environment(JARCOMSTR = "JARchiving $SOURCES into $TARGET")
JARFLAGS
General options passed to the Java archive tool. By default this is set to cf to create the
necessary jar file.
JARSUFFIX
The suffix for Java archives: .jar by default.
JAVABOOTCLASSPATH
Specifies the list of directories that will be added to the &javac; command line via the
-bootclasspath option. The individual directory names will be separated by the operating system's
path separate character (: on UNIX/Linux/POSIX, ; on Windows).
JAVAC The Java compiler.
JAVACCOM
The command line used to compile a directory tree containing Java source files to corresponding
Java class files. Any options specified in the $JAVACFLAGS construction variable are included on
this command line.
JAVACCOMSTR
The string displayed when compiling a directory tree of Java source files to corresponding Java
class files. If this is not set, then $JAVACCOM (the command line) is displayed.
env = Environment(JAVACCOMSTR = "Compiling class files $TARGETS from $SOURCES")
JAVACFLAGS
General options that are passed to the Java compiler.
JAVACLASSDIR
The directory in which Java class files may be found. This is stripped from the beginning of any
Java .class file names supplied to the JavaH builder.
JAVACLASSPATH
Specifies the list of directories that will be searched for Java .class file. The directories in
this list will be added to the &javac; and &javah; command lines via the -classpath option. The
individual directory names will be separated by the operating system's path separate character (:
on UNIX/Linux/POSIX, ; on Windows).
Note that this currently just adds the specified directory via the -classpath option. &SCons;
does not currently search the $JAVACLASSPATH directories for dependency .class files.
JAVACLASSSUFFIX
The suffix for Java class files; .class by default.
JAVAH The Java generator for C header and stub files.
JAVAHCOM
The command line used to generate C header and stub files from Java classes. Any options
specified in the $JAVAHFLAGS construction variable are included on this command line.
JAVAHCOMSTR
The string displayed when C header and stub files are generated from Java classes. If this is not
set, then $JAVAHCOM (the command line) is displayed.
env = Environment(JAVAHCOMSTR = "Generating header/stub file(s) $TARGETS from $SOURCES")
JAVAHFLAGS
General options passed to the C header and stub file generator for Java classes.
JAVASOURCEPATH
Specifies the list of directories that will be searched for input .java file. The directories in
this list will be added to the &javac; command line via the -sourcepath option. The individual
directory names will be separated by the operating system's path separate character (: on
UNIX/Linux/POSIX, ; on Windows).
Note that this currently just adds the specified directory via the -sourcepath option. &SCons;
does not currently search the $JAVASOURCEPATH directories for dependency .java files.
JAVASUFFIX
The suffix for Java files; .java by default.
JAVAVERSION
Specifies the Java version being used by the Java() builder. This is not currently used to select
one version of the Java compiler vs. another. Instead, you should set this to specify the version
of Java supported by your &javac; compiler. The default is 1.4.
This is sometimes necessary because Java 1.5 changed the file names that are created for nested
anonymous inner classes, which can cause a mismatch with the files that &SCons; expects will be
generated by the &javac; compiler. Setting $JAVAVERSION to 1.5 (or 1.6, as appropriate) can make
&SCons; realize that a Java 1.5 or 1.6 build is actually up to date.
LATEX The LaTeX structured formatter and typesetter.
LATEXCOM
The command line used to call the LaTeX structured formatter and typesetter.
LATEXCOMSTR
The string displayed when calling the LaTeX structured formatter and typesetter. If this is not
set, then $LATEXCOM (the command line) is displayed.
env = Environment(LATEXCOMSTR = "Building $TARGET from LaTeX input $SOURCES")
LATEXFLAGS
General options passed to the LaTeX structured formatter and typesetter.
LATEXRETRIES
The maximum number of times that LaTeX will be re-run if the .log generated by the $LATEXCOM
command indicates that there are undefined references. The default is to try to resolve undefined
references by re-running LaTeX up to three times.
LATEXSUFFIXES
The list of suffixes of files that will be scanned for LaTeX implicit dependencies (\include or
\import files). The default list is:
[".tex", ".ltx", ".latex"]
LDMODULE
The linker for building loadable modules. By default, this is the same as $SHLINK.
LDMODULECOM
The command line for building loadable modules. On Mac OS X, this uses the $LDMODULE,
$LDMODULEFLAGS and $FRAMEWORKSFLAGS variables. On other systems, this is the same as $SHLINK.
LDMODULECOMSTR
The string displayed when building loadable modules. If this is not set, then $LDMODULECOM (the
command line) is displayed.
LDMODULEFLAGS
General user options passed to the linker for building loadable modules.
LDMODULEPREFIX
The prefix used for loadable module file names. On Mac OS X, this is null; on other systems, this
is the same as $SHLIBPREFIX.
LDMODULESUFFIX
The suffix used for loadable module file names. On Mac OS X, this is null; on other systems, this
is the same as $SHLIBSUFFIX.
LEX The lexical analyzer generator.
LEXCOM The command line used to call the lexical analyzer generator to generate a source file.
LEXCOMSTR
The string displayed when generating a source file using the lexical analyzer generator. If this
is not set, then $LEXCOM (the command line) is displayed.
env = Environment(LEXCOMSTR = "Lex'ing $TARGET from $SOURCES")
LEXFLAGS
General options passed to the lexical analyzer generator.
_LIBDIRFLAGS
An automatically-generated construction variable containing the linker command-line options for
specifying directories to be searched for library. The value of $_LIBDIRFLAGS is created by
appending $LIBDIRPREFIX and $LIBDIRSUFFIX to the beginning and end of each directory in $LIBPATH.
LIBDIRPREFIX
The prefix used to specify a library directory on the linker command line. This will be appended
to the beginning of each directory in the $LIBPATH construction variable when the $_LIBDIRFLAGS
variable is automatically generated.
LIBDIRSUFFIX
The suffix used to specify a library directory on the linker command line. This will be appended
to the end of each directory in the $LIBPATH construction variable when the $_LIBDIRFLAGS variable
is automatically generated.
LIBEMITTER
TODO
_LIBFLAGS
An automatically-generated construction variable containing the linker command-line options for
specifying libraries to be linked with the resulting target. The value of $_LIBFLAGS is created
by appending $LIBLINKPREFIX and $LIBLINKSUFFIX to the beginning and end of each filename in $LIBS.
LIBLINKPREFIX
The prefix used to specify a library to link on the linker command line. This will be appended to
the beginning of each library in the $LIBS construction variable when the $_LIBFLAGS variable is
automatically generated.
LIBLINKSUFFIX
The suffix used to specify a library to link on the linker command line. This will be appended to
the end of each library in the $LIBS construction variable when the $_LIBFLAGS variable is
automatically generated.
LIBPATH
The list of directories that will be searched for libraries. The implicit dependency scanner will
search these directories for include files. Don't explicitly put include directory arguments in
$LINKFLAGS or $SHLINKFLAGS because the result will be non-portable and the directories will not be
searched by the dependency scanner. Note: directory names in LIBPATH will be looked-up relative to
the SConscript directory when they are used in a command. To force scons to look-up a directory
relative to the root of the source tree use #:
env = Environment(LIBPATH='#/libs')
The directory look-up can also be forced using the Dir() function:
libs = Dir('libs')
env = Environment(LIBPATH=libs)
The directory list will be added to command lines through the automatically-generated
$_LIBDIRFLAGS construction variable, which is constructed by appending the values of the
$LIBDIRPREFIXand$LIBDIRSUFFIX construction variables to the beginning and end of each directory in
$LIBPATH. Any command lines you define that need the LIBPATH directory list should include
$_LIBDIRFLAGS:
env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")
LIBPREFIX
The prefix used for (static) library file names. A default value is set for each platform (posix,
win32, os2, etc.), but the value is overridden by individual tools (ar, mslib, sgiar, sunar, tlib,
etc.) to reflect the names of the libraries they create.
LIBPREFIXES
A list of all legal prefixes for library file names. When searching for library dependencies,
SCons will look for files with these prefixes, the base library name, and suffixes in the
$LIBSUFFIXES list.
LIBS A list of one or more libraries that will be linked with any executable programs created by this
environment.
The library list will be added to command lines through the automatically-generated $_LIBFLAGS
construction variable, which is constructed by appending the values of the
$LIBLINKPREFIXand$LIBLINKSUFFIX construction variables to the beginning and end of each filename
in $LIBS. Any command lines you define that need the LIBS library list should include $_LIBFLAGS:
env = Environment(LINKCOM="my_linker $_LIBDIRFLAGS $_LIBFLAGS -o $TARGET $SOURCE")
If you add a File object to the $LIBS list, the name of that file will be added to $_LIBFLAGS, and
thus the link line, as is, without $LIBLINKPREFIX or $LIBLINKSUFFIX. For example:
env.Append(LIBS=File('/tmp/mylib.so'))
In all cases, scons will add dependencies from the executable program to all the libraries in this
list.
LIBSUFFIX
The suffix used for (static) library file names. A default value is set for each platform (posix,
win32, os2, etc.), but the value is overridden by individual tools (ar, mslib, sgiar, sunar, tlib,
etc.) to reflect the names of the libraries they create.
LIBSUFFIXES
A list of all legal suffixes for library file names. When searching for library dependencies,
SCons will look for files with prefixes, in the $LIBPREFIXES list, the base library name, and
these suffixes.
LICENSE
The abbreviated name of the license under which this project is released (gpl, lpgl, bsd etc.).
See http://www.opensource.org/licenses/alphabetical for a list of license names.
LINESEPARATOR
The separator used by the Substfile() and Textfile() builders. This value is used between sources
when constructing the target. It defaults to the current system line separator.
LINGUAS_FILE
The $LINGUAS_FILE defines file(s) containing list of additional linguas to be processed by
POInit(), POUpdate() or MOFiles() builders. It also affects Translate() builder. If the variable
contains a string, it defines name of the list file. The $LINGUAS_FILE may be a list of file names
as well. If $LINGUAS_FILE is set to True (or non-zero numeric value), the list will be read from
default file named LINGUAS.
LINK The linker.
LINKCOM
The command line used to link object files into an executable.
LINKCOMSTR
The string displayed when object files are linked into an executable. If this is not set, then
$LINKCOM (the command line) is displayed.
env = Environment(LINKCOMSTR = "Linking $TARGET")
LINKFLAGS
General user options passed to the linker. Note that this variable should not contain -l (or
similar) options for linking with the libraries listed in $LIBS, nor -L (or similar) library
search path options that scons generates automatically from $LIBPATH. See $_LIBFLAGS above, for
the variable that expands to library-link options, and $_LIBDIRFLAGS above, for the variable that
expands to library search path options.
M4 The M4 macro preprocessor.
M4COM The command line used to pass files through the M4 macro preprocessor.
M4COMSTR
The string displayed when a file is passed through the M4 macro preprocessor. If this is not set,
then $M4COM (the command line) is displayed.
M4FLAGS
General options passed to the M4 macro preprocessor.
MAKEINDEX
The makeindex generator for the TeX formatter and typesetter and the LaTeX structured formatter
and typesetter.
MAKEINDEXCOM
The command line used to call the makeindex generator for the TeX formatter and typesetter and the
LaTeX structured formatter and typesetter.
MAKEINDEXCOMSTR
The string displayed when calling the makeindex generator for the TeX formatter and typesetter and
the LaTeX structured formatter and typesetter. If this is not set, then $MAKEINDEXCOM (the
command line) is displayed.
MAKEINDEXFLAGS
General options passed to the makeindex generator for the TeX formatter and typesetter and the
LaTeX structured formatter and typesetter.
MAXLINELENGTH
The maximum number of characters allowed on an external command line. On Win32 systems, link
lines longer than this many characters are linked via a temporary file name.
MIDL The Microsoft IDL compiler.
MIDLCOM
The command line used to pass files to the Microsoft IDL compiler.
MIDLCOMSTR
The string displayed when the Microsoft IDL copmiler is called. If this is not set, then $MIDLCOM
(the command line) is displayed.
MIDLFLAGS
General options passed to the Microsoft IDL compiler.
MOSUFFIX
Suffix used for MO files (default: '.mo'). See &t-link-msgfmt; tool and MOFiles() builder.
MSGFMT Absolute path to msgfmt(1) binary, found by Detect(). See &t-link-msgfmt; tool and MOFiles()
builder.
MSGFMTCOM
Complete command line to run msgfmt(1) program. See &t-link-msgfmt; tool and MOFiles() builder.
MSGFMTCOMSTR
String to display when msgfmt(1) is invoked (default: '', which means ``print $MSGFMTCOM''). See
&t-link-msgfmt; tool and MOFiles() builder.
MSGFMTFLAGS
Additional flags to msgfmt(1). See &t-link-msgfmt; tool and MOFiles() builder.
MSGINIT
Path to msginit(1) program (found via Detect()). See &t-link-msginit; tool and POInit() builder.
MSGINITCOM
Complete command line to run msginit(1) program. See &t-link-msginit; tool and POInit() builder.
MSGINITCOMSTR
String to display when msginit(1) is invoked (default: '', which means ``print $MSGINITCOM'').
See &t-link-msginit; tool and POInit() builder.
MSGINITFLAGS
List of additional flags to msginit(1) (default: []). See &t-link-msginit; tool and POInit()
builder.
_MSGINITLOCALE
Internal ``macro''. Computes locale (language) name based on target filename (default:
'${TARGET.filebase}' ).
MSGMERGE
Absolute path to msgmerge(1) binary as found by Detect(). See &t-link-msgmerge; tool and
POUpdate() builder.
MSGMERGECOM
Complete command line to run msgmerge(1) command. See &t-link-msgmerge; tool and POUpdate()
builder.
MSGMERGECOMSTR
String to be displayed when msgmerge(1) is invoked (default: '', which means ``print
$MSGMERGECOM''). See &t-link-msgmerge; tool and POUpdate() builder.
MSGMERGEFLAGS
Additional flags to msgmerge(1) command. See &t-link-msgmerge; tool and POUpdate() builder.
MSSDK_DIR
The directory containing the Microsoft SDK (either Platform SDK or Windows SDK) to be used for
compilation.
MSSDK_VERSION
The version string of the Microsoft SDK (either Platform SDK or Windows SDK) to be used for
compilation. Supported versions include 6.1, 6.0A, 6.0, 2003R2 and 2003R1.
MSVC_BATCH
When set to any true value, specifies that SCons should batch compilation of object files when
calling the Microsoft Visual C/C++ compiler. All compilations of source files from the same
source directory that generate target files in a same output directory and were configured in
SCons using the same construction environment will be built in a single call to the compiler.
Only source files that have changed since their object files were built will be passed to each
compiler invocation (via the $CHANGED_SOURCES construction variable). Any compilations where the
object (target) file base name (minus the .obj) does not match the source file base name will be
compiled separately.
MSVC_USE_SCRIPT
Use a batch script to set up Microsoft Visual Studio compiler
$MSVC_USE_SCRIPToverrides$MSVC_VERSIONand$TARGET_ARCH. If set to the name of a Visual Studio .bat
file (e.g. vcvars.bat), SCons will run that bat file and extract the relevant variables from the
result (typically %INCLUDE%, %LIB%, and %PATH%). Setting MSVC_USE_SCRIPT to None bypasses the
Visual Studio autodetection entirely; use this if you are running SCons in a Visual Studio cmd
window and importing the shell's environment variables.
MSVC_VERSION
Sets the preferred version of Microsoft Visual C/C++ to use.
If $MSVC_VERSION is not set, SCons will (by default) select the latest version of Visual C/C++
installed on your system. If the specified version isn't installed, tool initialization will
fail. This variable must be passed as an argument to the Environment() constructor; setting it
later has no effect. Set it to an unexpected value (e.g. "XXX") to see the valid values on your
system.
MSVS When the Microsoft Visual Studio tools are initialized, they set up this dictionary with the
following keys:
VERSION: the version of MSVS being used (can be set via $MSVS_VERSION)
VERSIONS: the available versions of MSVS installed
VCINSTALLDIR: installed directory of Visual C++
VSINSTALLDIR: installed directory of Visual Studio
FRAMEWORKDIR: installed directory of the .NET framework
FRAMEWORKVERSIONS: list of installed versions of the .NET framework, sorted latest to oldest.
FRAMEWORKVERSION: latest installed version of the .NET framework
FRAMEWORKSDKDIR: installed location of the .NET SDK.
PLATFORMSDKDIR: installed location of the Platform SDK.
PLATFORMSDK_MODULES: dictionary of installed Platform SDK modules, where the dictionary keys are
keywords for the various modules, and the values are 2-tuples where the first is the release date,
and the second is the version number.
If a value isn't set, it wasn't available in the registry.
MSVS_ARCH
Sets the architecture for which the generated project(s) should build.
The default value is x86. amd64 is also supported by &SCons; for some Visual Studio versions.
Trying to set $MSVS_ARCH to an architecture that's not supported for a given Visual Studio version
will generate an error.
MSVS_PROJECT_GUID
The string placed in a generated Microsoft Visual Studio project file as the value of the
ProjectGUID attribute. There is no default value. If not defined, a new GUID is generated.
MSVS_SCC_AUX_PATH
The path name placed in a generated Microsoft Visual Studio project file as the value of the
SccAuxPath attribute if the MSVS_SCC_PROVIDER construction variable is also set. There is no
default value.
MSVS_SCC_CONNECTION_ROOT
The root path of projects in your SCC workspace, i.e the path under which all project and solution
files will be generated. It is used as a reference path from which the relative paths of the
generated Microsoft Visual Studio project and solution files are computed. The relative project
file path is placed as the value of the SccLocalPath attribute of the project file and as the
values of the SccProjectFilePathRelativizedFromConnection[i] (where [i] ranges from 0 to the
number of projects in the solution) attributes of the GlobalSection(SourceCodeControl) section of
the Microsoft Visual Studio solution file. Similarly the relative solution file path is placed as
the values of the SccLocalPath[i] (where [i] ranges from 0 to the number of projects in the
solution) attributes of the GlobalSection(SourceCodeControl) section of the Microsoft Visual
Studio solution file. This is used only if the MSVS_SCC_PROVIDER construction variable is also
set. The default value is the current working directory.
MSVS_SCC_PROJECT_NAME
The project name placed in a generated Microsoft Visual Studio project file as the value of the
SccProjectName attribute if the MSVS_SCC_PROVIDER construction variable is also set. In this case
the string is also placed in the SccProjectName0 attribute of the GlobalSection(SourceCodeControl)
section of the Microsoft Visual Studio solution file. There is no default value.
MSVS_SCC_PROVIDER
The string placed in a generated Microsoft Visual Studio project file as the value of the
SccProvider attribute. The string is also placed in the SccProvider0 attribute of the
GlobalSection(SourceCodeControl) section of the Microsoft Visual Studio solution file. There is
no default value.
MSVS_VERSION
Sets the preferred version of Microsoft Visual Studio to use.
If $MSVS_VERSION is not set, &SCons; will (by default) select the latest version of Visual Studio
installed on your system. So, if you have version 6 and version 7 (MSVS .NET) installed, it will
prefer version 7. You can override this by specifying the MSVS_VERSION variable in the
Environment initialization, setting it to the appropriate version ('6.0' or '7.0', for example).
If the specified version isn't installed, tool initialization will fail.
This is obsolete: use $MSVC_VERSION instead. If $MSVS_VERSION is set and
$MSVC_VERSIONisnot,$MSVC_VERSIONwillbesetautomaticallyto$MSVS_VERSION. If both are set to
different values, scons will raise an error.
MSVSBUILDCOM
The build command line placed in a generated Microsoft Visual Studio project file. The default is
to have Visual Studio invoke SCons with any specified build targets.
MSVSCLEANCOM
The clean command line placed in a generated Microsoft Visual Studio project file. The default is
to have Visual Studio invoke SCons with the -c option to remove any specified targets.
MSVSENCODING
The encoding string placed in a generated Microsoft Visual Studio project file. The default is
encoding Windows-1252.
MSVSPROJECTCOM
The action used to generate Microsoft Visual Studio project files.
MSVSPROJECTSUFFIX
The suffix used for Microsoft Visual Studio project (DSP) files. The default value is .vcproj
when using Visual Studio version 7.x (.NET) or later version, and .dsp when using earlier versions
of Visual Studio.
MSVSREBUILDCOM
The rebuild command line placed in a generated Microsoft Visual Studio project file. The default
is to have Visual Studio invoke SCons with any specified rebuild targets.
MSVSSCONS
The SCons used in generated Microsoft Visual Studio project files. The default is the version of
SCons being used to generate the project file.
MSVSSCONSCOM
The default SCons command used in generated Microsoft Visual Studio project files.
MSVSSCONSCRIPT
The sconscript file (that is, SConstruct or SConscript file) that will be invoked by Visual Studio
project files (through the $MSVSSCONSCOM variable). The default is the same sconscript file that
contains the call to MSVSProject() to build the project file.
MSVSSCONSFLAGS
The SCons flags used in generated Microsoft Visual Studio project files.
MSVSSOLUTIONCOM
The action used to generate Microsoft Visual Studio solution files.
MSVSSOLUTIONSUFFIX
The suffix used for Microsoft Visual Studio solution (DSW) files. The default value is .sln when
using Visual Studio version 7.x (.NET), and .dsw when using earlier versions of Visual Studio.
MT The program used on Windows systems to embed manifests into DLLs and EXEs. See also
$WINDOWS_EMBED_MANIFEST.
MTEXECOM
The Windows command line used to embed manifests into executables. See also $MTSHLIBCOM.
MTFLAGS
Flags passed to the $MT manifest embedding program (Windows only).
MTSHLIBCOM
The Windows command line used to embed manifests into shared libraries (DLLs). See also
$MTEXECOM.
MWCW_VERSION
The version number of the MetroWerks CodeWarrior C compiler to be used.
MWCW_VERSIONS
A list of installed versions of the MetroWerks CodeWarrior C compiler on this system.
NAME Specfies the name of the project to package.
no_import_lib
When set to non-zero, suppresses creation of a corresponding Windows static import lib by the
SharedLibrary builder when used with MinGW, Microsoft Visual Studio or Metrowerks. This also
suppresses creation of an export (.exp) file when using Microsoft Visual Studio.
OBJPREFIX
The prefix used for (static) object file names.
OBJSUFFIX
The suffix used for (static) object file names.
P4 The Perforce executable.
P4COM The command line used to fetch source files from Perforce.
P4COMSTR
The string displayed when fetching a source file from Perforce. If this is not set, then $P4COM
(the command line) is displayed.
P4FLAGS
General options that are passed to Perforce.
PACKAGEROOT
Specifies the directory where all files in resulting archive will be placed if applicable. The
default value is "$NAME-$VERSION".
PACKAGETYPE
Selects the package type to build. Currently these are available:
* msi - Microsoft Installer
* rpm - Redhat Package Manger
* ipkg - Itsy Package Management System
* tarbz2 - compressed tar
* targz - compressed tar
* zip - zip file
* src_tarbz2 - compressed tar source
* src_targz - compressed tar source
* src_zip - zip file source
This may be overridden with the "package_type" command line option.
PACKAGEVERSION
The version of the package (not the underlying project). This is currently only used by the rpm
packager and should reflect changes in the packaging, not the underlying project code itself.
PCH The Microsoft Visual C++ precompiled header that will be used when compiling object files. This
variable is ignored by tools other than Microsoft Visual C++. When this variable is defined SCons
will add options to the compiler command line to cause it to use the precompiled header, and will
also set up the dependencies for the PCH file. Example:
env['PCH'] = 'StdAfx.pch'
PCHCOM The command line used by the PCH() builder to generated a precompiled header.
PCHCOMSTR
The string displayed when generating a precompiled header. If this is not set, then $PCHCOM (the
command line) is displayed.
PCHPDBFLAGS
A construction variable that, when expanded, adds the /yD flag to the command line only if the
$PDB construction variable is set.
PCHSTOP
This variable specifies how much of a source file is precompiled. This variable is ignored by
tools other than Microsoft Visual C++, or when the PCH variable is not being used. When this
variable is define it must be a string that is the name of the header that is included at the end
of the precompiled portion of the source files, or the empty string if the "#pragma hrdstop"
construct is being used:
env['PCHSTOP'] = 'StdAfx.h'
PDB The Microsoft Visual C++ PDB file that will store debugging information for object files, shared
libraries, and programs. This variable is ignored by tools other than Microsoft Visual C++. When
this variable is defined SCons will add options to the compiler and linker command line to cause
them to generate external debugging information, and will also set up the dependencies for the PDB
file. Example:
env['PDB'] = 'hello.pdb'
The Visual C++ compiler switch that SCons uses by default to generate PDB information is /Z7.
This works correctly with parallel (-j) builds because it embeds the debug information in the
intermediate object files, as opposed to sharing a single PDB file between multiple object files.
This is also the only way to get debug information embedded into a static library. Using the /Zi
instead may yield improved link-time performance, although parallel builds will no longer work.
You can generate PDB files with the /Zi switch by overriding the default $CCPDBFLAGS variable; see
the entry for that variable for specific examples.
PDFCOM A deprecated synonym for $DVIPDFCOM.
PDFLATEX
The &pdflatex; utility.
PDFLATEXCOM
The command line used to call the &pdflatex; utility.
PDFLATEXCOMSTR
The string displayed when calling the &pdflatex; utility. If this is not set, then $PDFLATEXCOM
(the command line) is displayed.
env = Environment(PDFLATEX;COMSTR = "Building $TARGET from LaTeX input $SOURCES")
PDFLATEXFLAGS
General options passed to the &pdflatex; utility.
PDFPREFIX
The prefix used for PDF file names.
PDFSUFFIX
The suffix used for PDF file names.
PDFTEX The &pdftex; utility.
PDFTEXCOM
The command line used to call the &pdftex; utility.
PDFTEXCOMSTR
The string displayed when calling the &pdftex; utility. If this is not set, then $PDFTEXCOM (the
command line) is displayed.
env = Environment(PDFTEXCOMSTR = "Building $TARGET from TeX input $SOURCES")
PDFTEXFLAGS
General options passed to the &pdftex; utility.
PKGCHK On Solaris systems, the package-checking program that will be used (along with $PKGINFO) to look
for installed versions of the Sun PRO C++ compiler. The default is /usr/sbin/pgkchk.
PKGINFO
On Solaris systems, the package information program that will be used (along with $PKGCHK) to look
for installed versions of the Sun PRO C++ compiler. The default is pkginfo.
PLATFORM
The name of the platform used to create the Environment. If no platform is specified when the
Environment is created, scons autodetects the platform.
env = Environment(tools = [])
if env['PLATFORM'] == 'cygwin':
Tool('mingw')(env)
else:
Tool('msvc')(env)
POAUTOINIT
The $POAUTOINIT variable, if set to True (on non-zero numeric value), let the &t-link-msginit;
tool to automatically initialize missing PO files with msginit(1). This applies to both, POInit()
and POUpdate() builders (and others that use any of them).
POCREATE_ALIAS
Common alias for all PO files created with POInit() builder (default: 'po-create'). See &t-link-
msginit; tool and POInit() builder.
POSUFFIX
Suffix used for PO files (default: '.po') See &t-link-msginit; tool and POInit() builder.
POTDOMAIN
The $POTDOMAIN defines default domain, used to generate POT filename as $POTDOMAIN.pot when no POT
file name is provided by the user. This applies to POTUpdate(), POInit() and POUpdate() builders
(and builders, that use them, e.g. Translate()). Normally (if $POTDOMAIN is not defined), the
builders use messages.pot as default POT file name.
POTSUFFIX
Suffix used for PO Template files (default: '.pot'). See &t-link-xgettext; tool and POTUpdate()
builder.
POTUPDATE_ALIAS
Name of the common phony target for all PO Templates created with POUpdate()(default:'pot-
update'). See &t-link-xgettext; tool and POTUpdate() builder.
POUPDATE_ALIAS
Common alias for all PO files being defined with POUpdate()builder(default:'po-update'). See &t-
link-msgmerge; tool and POUpdate() builder.
PRINT_CMD_LINE_FUNC
A Python function used to print the command lines as they are executed (assuming command printing
is not disabled by the -q or -s options or their equivalents). The function should take four
arguments: s, the command being executed (a string), target, the target being built (file node,
list, or string name(s)), source, the source(s) used (file node, list, or string name(s)), and
env, the environment being used.
The function must do the printing itself. The default implementation, used if this variable is
not set or is None, is:
def print_cmd_line(s, target, source, env):
sys.stdout.write(s + "\n")
Here's an example of a more interesting function:
def print_cmd_line(s, target, source, env):
sys.stdout.write("Building %s -> %s...\n" %
(' and '.join([str(x) for x in source]),
' and '.join([str(x) for x in target])))
env=Environment(PRINT_CMD_LINE_FUNC=print_cmd_line)
env.Program('foo', 'foo.c')
This just prints "Building targetname from sourcename..." instead of the actual commands. Such a
function could also log the actual commands to a log file, for example.
PROGEMITTER
TODO
PROGPREFIX
The prefix used for executable file names.
PROGSUFFIX
The suffix used for executable file names.
PSCOM The command line used to convert TeX DVI files into a PostScript file.
PSCOMSTR
The string displayed when a TeX DVI file is converted into a PostScript file. If this is not set,
then $PSCOM (the command line) is displayed.
PSPREFIX
The prefix used for PostScript file names.
PSSUFFIX
The prefix used for PostScript file names.
QT_AUTOSCAN
Turn off scanning for mocable files. Use the Moc Builder to explicitly specify files to run moc
on.
QT_BINPATH
The path where the qt binaries are installed. The default value is '$QTDIR/bin'.
QT_CPPPATH
The path where the qt header files are installed. The default value is '$QTDIR/include'. Note:
If you set this variable to None, the tool won't change the $CPPPATH construction variable.
QT_DEBUG
Prints lots of debugging information while scanning for moc files.
QT_LIB Default value is 'qt'. You may want to set this to 'qt-mt'. Note: If you set this variable to
None, the tool won't change the $LIBS variable.
QT_LIBPATH
The path where the qt libraries are installed. The default value is '$QTDIR/lib'. Note: If you
set this variable to None, the tool won't change the $LIBPATH construction variable.
QT_MOC Default value is '$QT_BINPATH/moc'.
QT_MOCCXXPREFIX
Default value is ''. Prefix for moc output files, when source is a cxx file.
QT_MOCCXXSUFFIX
Default value is '.moc'. Suffix for moc output files, when source is a cxx file.
QT_MOCFROMCXXCOM
Command to generate a moc file from a cpp file.
QT_MOCFROMCXXCOMSTR
The string displayed when generating a moc file from a cpp file. If this is not set, then
$QT_MOCFROMCXXCOM (the command line) is displayed.
QT_MOCFROMCXXFLAGS
Default value is '-i'. These flags are passed to moc, when moccing a C++ file.
QT_MOCFROMHCOM
Command to generate a moc file from a header.
QT_MOCFROMHCOMSTR
The string displayed when generating a moc file from a cpp file. If this is not set, then
$QT_MOCFROMHCOM (the command line) is displayed.
QT_MOCFROMHFLAGS
Default value is ''. These flags are passed to moc, when moccing a header file.
QT_MOCHPREFIX
Default value is 'moc_'. Prefix for moc output files, when source is a header.
QT_MOCHSUFFIX
Default value is '$CXXFILESUFFIX'. Suffix for moc output files, when source is a header.
QT_UIC Default value is '$QT_BINPATH/uic'.
QT_UICCOM
Command to generate header files from .ui files.
QT_UICCOMSTR
The string displayed when generating header files from .ui files. If this is not set, then
$QT_UICCOM (the command line) is displayed.
QT_UICDECLFLAGS
Default value is ''. These flags are passed to uic, when creating a a h file from a .ui file.
QT_UICDECLPREFIX
Default value is ''. Prefix for uic generated header files.
QT_UICDECLSUFFIX
Default value is '.h'. Suffix for uic generated header files.
QT_UICIMPLFLAGS
Default value is ''. These flags are passed to uic, when creating a cxx file from a .ui file.
QT_UICIMPLPREFIX
Default value is 'uic_'. Prefix for uic generated implementation files.
QT_UICIMPLSUFFIX
Default value is '$CXXFILESUFFIX'. Suffix for uic generated implementation files.
QT_UISUFFIX
Default value is '.ui'. Suffix of designer input files.
QTDIR The qt tool tries to take this from os.environ. It also initializes all QT_* construction
variables listed below. (Note that all paths are constructed with python's os.path.join() method,
but are listed here with the '/' separator for easier reading.) In addition, the construction
environment variables $CPPPATH, $LIBPATH and $LIBS may be modified and the variables
$PROGEMITTER,$SHLIBEMITTERand$LIBEMITTER are modified. Because the build-performance is affected
when using this tool, you have to explicitly specify it at Environment creation:
Environment(tools=['default','qt'])
The qt tool supports the following operations:
Automatic moc file generation from header files. You do not have to specify moc files explicitly,
the tool does it for you. However, there are a few preconditions to do so: Your header file must
have the same filebase as your implementation file and must stay in the same directory. It must
have one of the suffixes .h, .hpp, .H, .hxx, .hh. You can turn off automatic moc file generation
by setting QT_AUTOSCAN to 0. See also the corresponding Moc()() builder method.
Automatic moc file generation from cxx files. As stated in the qt documentation, include the moc
file at the end of the cxx file. Note that you have to include the file, which is generated by the
transformation ${QT_MOCCXXPREFIX}<basename>${QT_MOCCXXSUFFIX}, by default <basename>.moc. A
warning is generated after building the moc file, if you do not include the correct file. If you
are using VariantDir, you may need to specify duplicate=1. You can turn off automatic moc file
generation by setting QT_AUTOSCAN to 0. See also the corresponding Moc() builder method.
Automatic handling of .ui files. The implementation files generated from .ui files are handled
much the same as yacc or lex files. Each .ui file given as a source of Program, Library or
SharedLibrary will generate three files, the declaration file, the implementation file and a moc
file. Because there are also generated headers, you may need to specify duplicate=1 in calls to
VariantDir. See also the corresponding Uic() builder method.
RANLIB The archive indexer.
RANLIBCOM
The command line used to index a static library archive.
RANLIBCOMSTR
The string displayed when a static library archive is indexed. If this is not set, then
$RANLIBCOM (the command line) is displayed.
env = Environment(RANLIBCOMSTR = "Indexing $TARGET")
RANLIBFLAGS
General options passed to the archive indexer.
RC The resource compiler used to build a Microsoft Visual C++ resource file.
RCCOM The command line used to build a Microsoft Visual C++ resource file.
RCCOMSTR
The string displayed when invoking the resource compiler to build a Microsoft Visual C++ resource
file. If this is not set, then $RCCOM (the command line) is displayed.
RCFLAGS
The flags passed to the resource compiler by the RES builder.
RCINCFLAGS
An automatically-generated construction variable containing the command-line options for
specifying directories to be searched by the resource compiler. The value of $RCINCFLAGS is
created by appending $RCINCPREFIX and $RCINCSUFFIX to the beginning and end of each directory in
$CPPPATH.
RCINCPREFIX
The prefix (flag) used to specify an include directory on the resource compiler command line.
This will be appended to the beginning of each directory in the $CPPPATH construction variable
when the $RCINCFLAGS variable is expanded.
RCINCSUFFIX
The suffix used to specify an include directory on the resource compiler command line. This will
be appended to the end of each directory in the $CPPPATH construction variable when the
$RCINCFLAGS variable is expanded.
RCS The RCS executable. Note that this variable is not actually used for the command to fetch source
files from RCS; see the $RCS_CO construction variable, below.
RCS_CO The RCS "checkout" executable, used to fetch source files from RCS.
RCS_COCOM
The command line used to fetch (checkout) source files from RCS.
RCS_COCOMSTR
The string displayed when fetching a source file from RCS. If this is not set, then $RCS_COCOM
(the command line) is displayed.
RCS_COFLAGS
Options that are passed to the $RCS_CO command.
RDirs A function that converts a string into a list of Dir instances by searching the repositories.
REGSVR The program used on Windows systems to register a newly-built DLL library whenever the
SharedLibrary() builder is passed a keyword argument of register=1.
REGSVRCOM
The command line used on Windows systems to register a newly-built DLL library whenever the
SharedLibrary() builder is passed a keyword argument of register=1.
REGSVRCOMSTR
The string displayed when registering a newly-built DLL file. If this is not set, then $REGSVRCOM
(the command line) is displayed.
REGSVRFLAGS
Flags passed to the DLL registration program on Windows systems when a newly-built DLL library is
registered. By default, this includes the /s that prevents dialog boxes from popping up and
requiring user attention.
RMIC The Java RMI stub compiler.
RMICCOM
The command line used to compile stub and skeleton class files from Java classes that contain RMI
implementations. Any options specified in the $RMICFLAGS construction variable are included on
this command line.
RMICCOMSTR
The string displayed when compiling stub and skeleton class files from Java classes that contain
RMI implementations. If this is not set, then $RMICCOM (the command line) is displayed.
env = Environment(RMICCOMSTR = "Generating stub/skeleton class files $TARGETS from $SOURCES")
RMICFLAGS
General options passed to the Java RMI stub compiler.
_RPATH An automatically-generated construction variable containing the rpath flags to be used when
linking a program with shared libraries. The value of $_RPATH is created by appending
$RPATHPREFIX and $RPATHSUFFIX to the beginning and end of each directory in $RPATH.
RPATH A list of paths to search for shared libraries when running programs. Currently only used in the
GNU (gnulink), IRIX (sgilink) and Sun (sunlink) linkers. Ignored on platforms and toolchains that
don't support it. Note that the paths added to RPATH are not transformed by scons in any way: if
you want an absolute path, you must make it absolute yourself.
RPATHPREFIX
The prefix used to specify a directory to be searched for shared libraries when running programs.
This will be appended to the beginning of each directory in the $RPATH construction variable when
the $_RPATH variable is automatically generated.
RPATHSUFFIX
The suffix used to specify a directory to be searched for shared libraries when running programs.
This will be appended to the end of each directory in the $RPATH construction variable when the
$_RPATH variable is automatically generated.
RPCGEN The RPC protocol compiler.
RPCGENCLIENTFLAGS
Options passed to the RPC protocol compiler when generating client side stubs. These are in
addition to any flags specified in the $RPCGENFLAGS construction variable.
RPCGENFLAGS
General options passed to the RPC protocol compiler.
RPCGENHEADERFLAGS
Options passed to the RPC protocol compiler when generating a header file. These are in addition
to any flags specified in the $RPCGENFLAGS construction variable.
RPCGENSERVICEFLAGS
Options passed to the RPC protocol compiler when generating server side stubs. These are in
addition to any flags specified in the $RPCGENFLAGS construction variable.
RPCGENXDRFLAGS
Options passed to the RPC protocol compiler when generating XDR routines. These are in addition
to any flags specified in the $RPCGENFLAGS construction variable.
SCANNERS
A list of the available implicit dependency scanners. New file scanners may be added by appending
to this list, although the more flexible approach is to associate scanners with a specific
Builder. See the sections "Builder Objects" and "Scanner Objects," below, for more information.
SCCS The SCCS executable.
SCCSCOM
The command line used to fetch source files from SCCS.
SCCSCOMSTR
The string displayed when fetching a source file from a CVS repository. If this is not set, then
$SCCSCOM (the command line) is displayed.
SCCSFLAGS
General options that are passed to SCCS.
SCCSGETFLAGS
Options that are passed specifically to the SCCS "get" subcommand. This can be set, for example,
to -e to check out editable files from SCCS.
SCONS_HOME
The (optional) path to the SCons library directory, initialized from the external environment. If
set, this is used to construct a shorter and more efficient search path in the $MSVSSCONS command
line executed from Microsoft Visual Studio project files.
SHCC The C compiler used for generating shared-library objects.
SHCCCOM
The command line used to compile a C source file to a shared-library object file. Any options
specified in the $SHCFLAGS, $SHCCFLAGS and $CPPFLAGS construction variables are included on this
command line.
SHCCCOMSTR
The string displayed when a C source file is compiled to a shared object file. If this is not
set, then $SHCCCOM (the command line) is displayed.
env = Environment(SHCCCOMSTR = "Compiling shared object $TARGET")
SHCCFLAGS
Options that are passed to the C and C++ compilers to generate shared-library objects.
SHCFLAGS
Options that are passed to the C compiler (only; not C++) to generate shared-library objects.
SHCXX The C++ compiler used for generating shared-library objects.
SHCXXCOM
The command line used to compile a C++ source file to a shared-library object file. Any options
specified in the $SHCXXFLAGS and $CPPFLAGS construction variables are included on this command
line.
SHCXXCOMSTR
The string displayed when a C++ source file is compiled to a shared object file. If this is not
set, then $SHCXXCOM (the command line) is displayed.
env = Environment(SHCXXCOMSTR = "Compiling shared object $TARGET")
SHCXXFLAGS
Options that are passed to the C++ compiler to generate shared-library objects.
SHELL A string naming the shell program that will be passed to the $SPAWN function. See the $SPAWN
construction variable for more information.
SHF77 The Fortran 77 compiler used for generating shared-library objects. You should normally set the
$SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You
only need to set $SHF77 if you need to use a specific compiler or compiler version for Fortran 77
files.
SHF77COM
The command line used to compile a Fortran 77 source file to a shared-library object file. You
only need to set $SHF77COM if you need to use a specific command line for Fortran 77 files. You
should normally set the $SHFORTRANCOM variable, which specifies the default command line for all
Fortran versions.
SHF77COMSTR
The string displayed when a Fortran 77 source file is compiled to a shared-library object file.
If this is not set, then $SHF77COM or $SHFORTRANCOM (the command line) is displayed.
SHF77FLAGS
Options that are passed to the Fortran 77 compiler to generated shared-library objects. You only
need to set $SHF77FLAGS if you need to define specific user options for Fortran 77 files. You
should normally set the $SHFORTRANFLAGS variable, which specifies the user-specified options
passed to the default Fortran compiler for all Fortran versions.
SHF77PPCOM
The command line used to compile a Fortran 77 source file to a shared-library object file after
first running the file through the C preprocessor. Any options specified in the $SHF77FLAGS and
$CPPFLAGS construction variables are included on this command line. You only need to set
$SHF77PPCOM if you need to use a specific C-preprocessor command line for Fortran 77 files. You
should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor
command line for all Fortran versions.
SHF77PPCOMSTR
The string displayed when a Fortran 77 source file is compiled to a shared-library object file
after first running the file through the C preprocessor. If this is not set, then $SHF77PPCOM or
$SHFORTRANPPCOM (the command line) is displayed.
SHF90 The Fortran 90 compiler used for generating shared-library objects. You should normally set the
$SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You
only need to set $SHF90 if you need to use a specific compiler or compiler version for Fortran 90
files.
SHF90COM
The command line used to compile a Fortran 90 source file to a shared-library object file. You
only need to set $SHF90COM if you need to use a specific command line for Fortran 90 files. You
should normally set the $SHFORTRANCOM variable, which specifies the default command line for all
Fortran versions.
SHF90COMSTR
The string displayed when a Fortran 90 source file is compiled to a shared-library object file.
If this is not set, then $SHF90COM or $SHFORTRANCOM (the command line) is displayed.
SHF90FLAGS
Options that are passed to the Fortran 90 compiler to generated shared-library objects. You only
need to set $SHF90FLAGS if you need to define specific user options for Fortran 90 files. You
should normally set the $SHFORTRANFLAGS variable, which specifies the user-specified options
passed to the default Fortran compiler for all Fortran versions.
SHF90PPCOM
The command line used to compile a Fortran 90 source file to a shared-library object file after
first running the file through the C preprocessor. Any options specified in the $SHF90FLAGS and
$CPPFLAGS construction variables are included on this command line. You only need to set
$SHF90PPCOM if you need to use a specific C-preprocessor command line for Fortran 90 files. You
should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor
command line for all Fortran versions.
SHF90PPCOMSTR
The string displayed when a Fortran 90 source file is compiled to a shared-library object file
after first running the file through the C preprocessor. If this is not set, then $SHF90PPCOM or
$SHFORTRANPPCOM (the command line) is displayed.
SHF95 The Fortran 95 compiler used for generating shared-library objects. You should normally set the
$SHFORTRAN variable, which specifies the default Fortran compiler for all Fortran versions. You
only need to set $SHF95 if you need to use a specific compiler or compiler version for Fortran 95
files.
SHF95COM
The command line used to compile a Fortran 95 source file to a shared-library object file. You
only need to set $SHF95COM if you need to use a specific command line for Fortran 95 files. You
should normally set the $SHFORTRANCOM variable, which specifies the default command line for all
Fortran versions.
SHF95COMSTR
The string displayed when a Fortran 95 source file is compiled to a shared-library object file.
If this is not set, then $SHF95COM or $SHFORTRANCOM (the command line) is displayed.
SHF95FLAGS
Options that are passed to the Fortran 95 compiler to generated shared-library objects. You only
need to set $SHF95FLAGS if you need to define specific user options for Fortran 95 files. You
should normally set the $SHFORTRANFLAGS variable, which specifies the user-specified options
passed to the default Fortran compiler for all Fortran versions.
SHF95PPCOM
The command line used to compile a Fortran 95 source file to a shared-library object file after
first running the file through the C preprocessor. Any options specified in the $SHF95FLAGS and
$CPPFLAGS construction variables are included on this command line. You only need to set
$SHF95PPCOM if you need to use a specific C-preprocessor command line for Fortran 95 files. You
should normally set the $SHFORTRANPPCOM variable, which specifies the default C-preprocessor
command line for all Fortran versions.
SHF95PPCOMSTR
The string displayed when a Fortran 95 source file is compiled to a shared-library object file
after first running the file through the C preprocessor. If this is not set, then $SHF95PPCOM or
$SHFORTRANPPCOM (the command line) is displayed.
SHFORTRAN
The default Fortran compiler used for generating shared-library objects.
SHFORTRANCOM
The command line used to compile a Fortran source file to a shared-library object file.
SHFORTRANCOMSTR
The string displayed when a Fortran source file is compiled to a shared-library object file. If
this is not set, then $SHFORTRANCOM (the command line) is displayed.
SHFORTRANFLAGS
Options that are passed to the Fortran compiler to generate shared-library objects.
SHFORTRANPPCOM
The command line used to compile a Fortran source file to a shared-library object file after first
running the file through the C preprocessor. Any options specified in the $SHFORTRANFLAGS and
$CPPFLAGS construction variables are included on this command line.
SHFORTRANPPCOMSTR
The string displayed when a Fortran source file is compiled to a shared-library object file after
first running the file through the C preprocessor. If this is not set, then $SHFORTRANPPCOM (the
command line) is displayed.
SHLIBEMITTER
TODO
SHLIBPREFIX
The prefix used for shared library file names.
SHLIBSUFFIX
The suffix used for shared library file names.
SHLIBVERSION
When this construction variable is defined, a versioned shared library is created. This modifies
the $SHLINKFLAGS as required, adds the version number to the library name, and creates the
symlinks that are needed. $SHLIBVERSION needs to be of the form X.Y.Z, where X and Y are numbers,
and Z is a number but can also contain letters to designate alpha, beta, or release candidate
patch levels.
SHLINK The linker for programs that use shared libraries.
SHLINKCOM
The command line used to link programs using shared libraries.
SHLINKCOMSTR
The string displayed when programs using shared libraries are linked. If this is not set, then
$SHLINKCOM (the command line) is displayed.
env = Environment(SHLINKCOMSTR = "Linking shared $TARGET")
SHLINKFLAGS
General user options passed to the linker for programs using shared libraries. Note that this
variable should not contain -l (or similar) options for linking with the libraries listed in
$LIBS, nor -L (or similar) include search path options that scons generates automatically from
$LIBPATH. See $_LIBFLAGS above, for the variable that expands to library-link options, and
$_LIBDIRFLAGS above, for the variable that expands to library search path options.
SHOBJPREFIX
The prefix used for shared object file names.
SHOBJSUFFIX
The suffix used for shared object file names.
SOURCE A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
SOURCE_URL
The URL (web address) of the location from which the project was retrieved. This is used to fill
in the Source: field in the controlling information for Ipkg and RPM packages.
SOURCES
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
SPAWN A command interpreter function that will be called to execute command line strings. The function
must expect the following arguments:
def spawn(shell, escape, cmd, args, env):
sh is a string naming the shell program to use. escape is a function that can be called to escape
shell special characters in the command line. cmd is the path to the command to be executed.
args is the arguments to the command. env is a dictionary of the environment variables in which
the command should be executed.
SUBST_DICT
The dictionary used by the Substfile() or Textfile() builders for substitution values. It can be
anything acceptable to the dict() constructor, so in addition to a dictionary, lists of tuples are
also acceptable.
SUBSTFILEPREFIX
The prefix used for Substfile() file names, the null string by default.
SUBSTFILESUFFIX
The suffix used for Substfile() file names, the null string by default.
SUMMARY
A short summary of what the project is about. This is used to fill in the Summary: field in the
controlling information for Ipkg and RPM packages, and as the Description: field in MSI packages.
SWIG The scripting language wrapper and interface generator.
SWIGCFILESUFFIX
The suffix that will be used for intermediate C source files generated by the scripting language
wrapper and interface generator. The default value is _wrap$CFILESUFFIX. By default, this value
is used whenever the -c++ option is not specified as part of the $SWIGFLAGS construction variable.
SWIGCOM
The command line used to call the scripting language wrapper and interface generator.
SWIGCOMSTR
The string displayed when calling the scripting language wrapper and interface generator. If this
is not set, then $SWIGCOM (the command line) is displayed.
SWIGCXXFILESUFFIX
The suffix that will be used for intermediate C++ source files generated by the scripting language
wrapper and interface generator. The default value is _wrap$CFILESUFFIX. By default, this value
is used whenever the -c++ option is specified as part of the $SWIGFLAGS construction variable.
SWIGDIRECTORSUFFIX
The suffix that will be used for intermediate C++ header files generated by the scripting language
wrapper and interface generator. These are only generated for C++ code when the SWIG 'directors'
feature is turned on. The default value is _wrap.h.
SWIGFLAGS
General options passed to the scripting language wrapper and interface generator. This is where
you should set -python, -perl5, -tcl, or whatever other options you want to specify to SWIG. If
you set the -c++ option in this variable, scons will, by default, generate a C++ intermediate
source file with the extension that is specified as the $CXXFILESUFFIX variable.
_SWIGINCFLAGS
An automatically-generated construction variable containing the SWIG command-line options for
specifying directories to be searched for included files. The value of $_SWIGINCFLAGS is created
by appending $SWIGINCPREFIX and $SWIGINCSUFFIX to the beginning and end of each directory in
$SWIGPATH.
SWIGINCPREFIX
The prefix used to specify an include directory on the SWIG command line. This will be appended
to the beginning of each directory in the $SWIGPATH construction variable when the $_SWIGINCFLAGS
variable is automatically generated.
SWIGINCSUFFIX
The suffix used to specify an include directory on the SWIG command line. This will be appended
to the end of each directory in the $SWIGPATH construction variable when the $_SWIGINCFLAGS
variable is automatically generated.
SWIGOUTDIR
Specifies the output directory in which the scripting language wrapper and interface generator
should place generated language-specific files. This will be used by SCons to identify the files
that will be generated by the &swig; call, and translated into the swig -outdir option on the
command line.
SWIGPATH
The list of directories that the scripting language wrapper and interface generate will search for
included files. The SWIG implicit dependency scanner will search these directories for include
files. The default is to use the same path specified as $CPPPATH.
Don't explicitly put include directory arguments in SWIGFLAGS; the result will be non-portable and
the directories will not be searched by the dependency scanner. Note: directory names in SWIGPATH
will be looked-up relative to the SConscript directory when they are used in a command. To force
scons to look-up a directory relative to the root of the source tree use #:
env = Environment(SWIGPATH='#/include')
The directory look-up can also be forced using the Dir() function:
include = Dir('include')
env = Environment(SWIGPATH=include)
The directory list will be added to command lines through the automatically-generated
$_SWIGINCFLAGS construction variable, which is constructed by appending the values of the
$SWIGINCPREFIXand$SWIGINCSUFFIX construction variables to the beginning and end of each directory
in $SWIGPATH. Any command lines you define that need the SWIGPATH directory list should include
$_SWIGINCFLAGS:
env = Environment(SWIGCOM="my_swig -o $TARGET $_SWIGINCFLAGS $SORUCES")
SWIGVERSION
The version number of the SWIG tool.
TAR The tar archiver.
TARCOM The command line used to call the tar archiver.
TARCOMSTR
The string displayed when archiving files using the tar archiver. If this is not set, then
$TARCOM (the command line) is displayed.
env = Environment(TARCOMSTR = "Archiving $TARGET")
TARFLAGS
General options passed to the tar archiver.
TARGET A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
TARGET_ARCH
Sets the target architecture for Visual Studio compiler (i.e. the arch of the binaries generated
by the compiler). If not set, default to $HOST_ARCH, or, if that is unset, to the architecture of
the running machine's OS (note that the python build or architecture has no effect). This
variable must be passed as an argument to the Environment() constructor; setting it later has no
effect. This is currently only used on Windows, but in the future it will be used on other OSes
as well.
Valid values for Windows are x86, i386 (for 32 bits); amd64, emt64, x86_64 (for 64 bits); and ia64
(Itanium). For example, if you want to compile 64-bit binaries, you would set
TARGET_ARCH='x86_64' in your SCons environment.
TARGET_OS
The name of the target operating system for the compiled objects
created by this Environment.
This defaults to the value of HOST_OS, and the user can override it.
Currently only set for Win32.
TARGETS
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
TARSUFFIX
The suffix used for tar file names.
TEMPFILEPREFIX
The prefix for a temporary file used to execute lines longer than $MAXLINELENGTH. The default is
'@'. This may be set for toolchains that use other values, such as '-@' for the diab compiler or
'-via' for ARM toolchain.
TEX The TeX formatter and typesetter.
TEXCOM The command line used to call the TeX formatter and typesetter.
TEXCOMSTR
The string displayed when calling the TeX formatter and typesetter. If this is not set, then
$TEXCOM (the command line) is displayed.
env = Environment(TEXCOMSTR = "Building $TARGET from TeX input $SOURCES")
TEXFLAGS
General options passed to the TeX formatter and typesetter.
TEXINPUTS
List of directories that the LaTeX program will search for include directories. The LaTeX
implicit dependency scanner will search these directories for \include and \import files.
TEXTFILEPREFIX
The prefix used for Textfile() file names, the null string by default.
TEXTFILESUFFIX
The suffix used for Textfile() file names; .txt by default.
TOOLS A list of the names of the Tool specifications that are part of this construction environment.
UNCHANGED_SOURCES
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
UNCHANGED_TARGETS
A reserved variable name that may not be set or used in a construction environment. (See
"Variable Substitution," below.)
VENDOR The person or organization who supply the packaged software. This is used to fill in the Vendor:
field in the controlling information for RPM packages, and the Manufacturer: field in the
controlling information for MSI packages.
VERSION
The version of the project, specified as a string.
WIN32_INSERT_DEF
A deprecated synonym for $WINDOWS_INSERT_DEF.
WIN32DEFPREFIX
A deprecated synonym for $WINDOWSDEFPREFIX.
WIN32DEFSUFFIX
A deprecated synonym for $WINDOWSDEFSUFFIX.
WIN32EXPPREFIX
A deprecated synonym for $WINDOWSEXPSUFFIX.
WIN32EXPSUFFIX
A deprecated synonym for $WINDOWSEXPSUFFIX.
WINDOWS_EMBED_MANIFEST
Set this variable to True or 1 to embed the compiler-generated manifest (normally
${TARGET}.manifest) into all Windows exes and DLLs built with this environment, as a resource
during their link step. This is done using $MT and $MTEXECOM and $MTSHLIBCOM.
WINDOWS_INSERT_DEF
When this is set to true, a library build of a Windows shared library (.dll file) will also build
a corresponding .def file at the same time, if a .def file is not already listed as a build
target. The default is 0 (do not build a .def file).
WINDOWS_INSERT_MANIFEST
When this is set to true, scons will be aware of the .manifest files generated by Microsoft Visua
C/C++ 8.
WINDOWSDEFPREFIX
The prefix used for Windows .def file names.
WINDOWSDEFSUFFIX
The suffix used for Windows .def file names.
WINDOWSEXPPREFIX
The prefix used for Windows .exp file names.
WINDOWSEXPSUFFIX
The suffix used for Windows .exp file names.
WINDOWSPROGMANIFESTPREFIX
The prefix used for executable program .manifest files generated by Microsoft Visual C/C++.
WINDOWSPROGMANIFESTSUFFIX
The suffix used for executable program .manifest files generated by Microsoft Visual C/C++.
WINDOWSSHLIBMANIFESTPREFIX
The prefix used for shared library .manifest files generated by Microsoft Visual C/C++.
WINDOWSSHLIBMANIFESTSUFFIX
The suffix used for shared library .manifest files generated by Microsoft Visual C/C++.
X_IPK_DEPENDS
This is used to fill in the Depends: field in the controlling information for Ipkg packages.
X_IPK_DESCRIPTION
This is used to fill in the Description: field in the controlling information for Ipkg packages.
The default value is $SUMMARY0DESCRIPTION
X_IPK_MAINTAINER
This is used to fill in the Maintainer: field in the controlling information for Ipkg packages.
X_IPK_PRIORITY
This is used to fill in the Priority: field in the controlling information for Ipkg packages.
X_IPK_SECTION
This is used to fill in the Section: field in the controlling information for Ipkg packages.
X_MSI_LANGUAGE
This is used to fill in the Language: attribute in the controlling information for MSI packages.
X_MSI_LICENSE_TEXT
The text of the software license in RTF format. Carriage return characters will be replaced with
the RTF equivalent \\par.
X_MSI_UPGRADE_CODE
TODO
X_RPM_AUTOREQPROV
This is used to fill in the AutoReqProv: field in the RPM .spec file.
X_RPM_BUILD
internal, but overridable
X_RPM_BUILDREQUIRES
This is used to fill in the BuildRequires: field in the RPM .spec file.
X_RPM_BUILDROOT
internal, but overridable
X_RPM_CLEAN
internal, but overridable
X_RPM_CONFLICTS
This is used to fill in the Conflicts: field in the RPM .spec file.
X_RPM_DEFATTR
This value is used as the default attributes for the files in the RPM package. The default value
is (-,root,root).
X_RPM_DISTRIBUTION
This is used to fill in the Distribution: field in the RPM .spec file.
X_RPM_EPOCH
This is used to fill in the Epoch: field in the controlling information for RPM packages.
X_RPM_EXCLUDEARCH
This is used to fill in the ExcludeArch: field in the RPM .spec file.
X_RPM_EXLUSIVEARCH
This is used to fill in the ExclusiveArch: field in the RPM .spec file.
X_RPM_GROUP
This is used to fill in the Group: field in the RPM .spec file.
X_RPM_GROUP_lang
This is used to fill in the Group(lang): field in the RPM .spec file. Note that lang is not
literal and should be replaced by the appropriate language code.
X_RPM_ICON
This is used to fill in the Icon: field in the RPM .spec file.
X_RPM_INSTALL
internal, but overridable
X_RPM_PACKAGER
This is used to fill in the Packager: field in the RPM .spec file.
X_RPM_POSTINSTALL
This is used to fill in the %post: section in the RPM .spec file.
X_RPM_POSTUNINSTALL
This is used to fill in the %postun: section in the RPM .spec file.
X_RPM_PREFIX
This is used to fill in the Prefix: field in the RPM .spec file.
X_RPM_PREINSTALL
This is used to fill in the %pre: section in the RPM .spec file.
X_RPM_PREP
internal, but overridable
X_RPM_PREUNINSTALL
This is used to fill in the %preun: section in the RPM .spec file.
X_RPM_PROVIDES
This is used to fill in the Provides: field in the RPM .spec file.
X_RPM_REQUIRES
This is used to fill in the Requires: field in the RPM .spec file.
X_RPM_SERIAL
This is used to fill in the Serial: field in the RPM .spec file.
X_RPM_URL
This is used to fill in the Url: field in the RPM .spec file.
XGETTEXT
Path to xgettext(1) program (found via Detect()). See &t-link-xgettext; tool and POTUpdate()
builder.
XGETTEXTCOM
Complete xgettext command line. See &t-link-xgettext; tool and POTUpdate() builder.
XGETTEXTCOMSTR
A string that is shown when xgettext(1) command is invoked (default: '', which means "print
$XGETTEXTCOM"). See &t-link-xgettext; tool and POTUpdate() builder.
_XGETTEXTDOMAIN
Internal "macro". Generates xgettext domain name form source and target (default:
'${TARGET.filebase}').
XGETTEXTFLAGS
Additional flags to xgettext(1). See &t-link-xgettext; tool and POTUpdate() builder.
XGETTEXTFROM
Name of file containing list of xgettext(1)'s source files. Autotools' users know this as
POTFILES.in so they will in most cases set XGETTEXTFROM="POTFILES.in" here. The $XGETTEXTFROM
files have same syntax and semantics as the well known GNU POTFILES.in. See &t-link-xgettext;
tool and POTUpdate() builder.
_XGETTEXTFROMFLAGS
Internal "macro". Genrates list of -D<dir> flags from the $XGETTEXTPATH list.
XGETTEXTFROMPREFIX
This flag is used to add single $XGETTEXTFROM file to xgettext(1)'s commandline (default: '-f').
XGETTEXTFROMSUFFIX
(default: '')
XGETTEXTPATH
List of directories, there xgettext(1) will look for source files (default: []). <note>This
variable works only together with $XGETTEXTFROM </para></note> See also &t-link-xgettext; tool and
POTUpdate() builder.
_XGETTEXTPATHFLAGS
Internal "macro". Generates list of -f<file> flags from $XGETTEXTFROM.
XGETTEXTPATHPREFIX
This flag is used to add single search path to xgettext(1)'s commandline (default: '-D').
XGETTEXTPATHSUFFIX
(default: '')
YACC The parser generator.
YACCCOM
The command line used to call the parser generator to generate a source file.
YACCCOMSTR
The string displayed when generating a source file using the parser generator. If this is not
set, then $YACCCOM (the command line) is displayed.
env = Environment(YACCCOMSTR = "Yacc'ing $TARGET from $SOURCES")
YACCFLAGS
General options passed to the parser generator. If $YACCFLAGS contains a -d option, SCons assumes
that the call will also create a .h file (if the yacc source file ends in a .y suffix) or a .hpp
file (if the yacc source file ends in a .yy suffix)
YACCHFILESUFFIX
The suffix of the C header file generated by the parser generator when the -d option is used.
Note that setting this variable does not cause the parser generator to generate a header file with
the specified suffix, it exists to allow you to specify what suffix the parser generator will use
of its own accord. The default value is .h.
YACCHXXFILESUFFIX
The suffix of the C++ header file generated by the parser generator when the -d option is used.
Note that setting this variable does not cause the parser generator to generate a header file with
the specified suffix, it exists to allow you to specify what suffix the parser generator will use
of its own accord. The default value is .hpp, except on Mac OS X, where the default is
${TARGET.suffix}.h. because the default &bison; parser generator just appends .h to the name of
the generated C++ file.
YACCVCGFILESUFFIX
The suffix of the file containing the VCG grammar automaton definition when the --graph= option is
used. Note that setting this variable does not cause the parser generator to generate a VCG file
with the specified suffix, it exists to allow you to specify what suffix the parser generator will
use of its own accord. The default value is .vcg.
ZIP The zip compression and file packaging utility.
ZIPCOM The command line used to call the zip utility, or the internal Python function used to create a
zip archive.
ZIPCOMPRESSION
The compression flag from the Python zipfile module used by the internal Python function to
control whether the zip archive is compressed or not. The default value is zipfile.ZIP_DEFLATED,
which creates a compressed zip archive. This value has no effect if the zipfile module is
unavailable.
ZIPCOMSTR
The string displayed when archiving files using the zip utility. If this is not set, then $ZIPCOM
(the command line or internal Python function) is displayed.
env = Environment(ZIPCOMSTR = "Zipping $TARGET")
ZIPFLAGS
General options passed to the zip utility.
ZIPSUFFIX
The suffix used for zip file names.
Construction variables can be retrieved and set using the Dictionary method of the construction
environment:
dict = env.Dictionary()
dict["CC"] = "cc"
or using the [] operator:
env["CC"] = "cc"
Construction variables can also be passed to the construction environment constructor:
env = Environment(CC="cc")
or when copying a construction environment using the Clone method:
env2 = env.Clone(CC="cl.exe")
Configure Contexts
scons supports configure contexts, an integrated mechanism similar to the various AC_CHECK macros in GNU
autoconf for testing for the existence of C header files, libraries, etc. In contrast to autoconf, scons
does not maintain an explicit cache of the tested values, but uses its normal dependency tracking to keep
the checked values up to date. However, users may override this behaviour with the --config command line
option.
The following methods can be used to perform checks:
Configure(env, [custom_tests, conf_dir, log_file, config_h, clean, help])
env.Configure([custom_tests, conf_dir, log_file, config_h, clean, help])
This creates a configure context, which can be used to perform checks. env specifies the
environment for building the tests. This environment may be modified when performing checks.
custom_tests is a dictionary containing custom tests. See also the section about custom tests
below. By default, no custom tests are added to the configure context. conf_dir specifies a
directory where the test cases are built. Note that this directory is not used for building
normal targets. The default value is the directory #/.sconf_temp. log_file specifies a file
which collects the output from commands that are executed to check for the existence of header
files, libraries, etc. The default is the file #/config.log. If you are using the VariantDir()
method, you may want to specify a subdirectory under your variant directory. config_h specifies a
C header file where the results of tests will be written, e.g. #define HAVE_STDIO_H, #define
HAVE_LIBM, etc. The default is to not write a config.h file. You can specify the same config.h
file in multiple calls to Configure, in which case scons will concatenate all results in the
specified file. Note that SCons uses its normal dependency checking to decide if it's necessary
to rebuild the specified config_h file. This means that the file is not necessarily re-built each
time scons is run, but is only rebuilt if its contents will have changed and some target that
depends on the config_h file is being built.
The optional clean and help arguments can be used to suppress execution of the configuration tests
when the -c/--clean or -H/-h/--help options are used, respectively. The default behavior is
always to execute configure context tests, since the results of the tests may affect the list of
targets to be cleaned or the help text. If the configure tests do not affect these, then you may
add the clean=False or help=False arguments (or both) to avoid unnecessary test execution.
A created Configure instance has the following associated methods:
SConf.Finish(context)
sconf.Finish()
This method should be called after configuration is done. It returns the environment as modified
by the configuration checks performed. After this method is called, no further checks can be
performed with this configuration context. However, you can create a new Configure context to
perform additional checks. Only one context should be active at a time.
The following Checks are predefined. (This list will likely grow larger as time goes by and
developers contribute new useful tests.)
SConf.CheckHeader(context, header, [include_quotes, language])
sconf.CheckHeader(header, [include_quotes, language])
Checks if header is usable in the specified language. header may be a list, in which case the
last item in the list is the header file to be checked, and the previous list items are header
files whose #include lines should precede the header line being checked for. The optional
argument include_quotes must be a two character string, where the first character denotes the
opening quote and the second character denotes the closing quote. By default, both characters
are " (double quote). The optional argument language should be either C or C++ and selects the
compiler to be used for the check. Returns 1 on success and 0 on failure.
SConf.CheckCHeader(context, header, [include_quotes])
sconf.CheckCHeader(header, [include_quotes])
This is a wrapper around SConf.CheckHeader which checks if header is usable in the C language.
header may be a list, in which case the last item in the list is the header file to be checked,
and the previous list items are header files whose #include lines should precede the header line
being checked for. The optional argument include_quotes must be a two character string, where the
first character denotes the opening quote and the second character denotes the closing quote (both
default to "). Returns 1 on success and 0 on failure.
SConf.CheckCXXHeader(context, header, [include_quotes])
sconf.CheckCXXHeader(header, [include_quotes])
This is a wrapper around SConf.CheckHeader which checks if header is usable in the C++ language.
header may be a list, in which case the last item in the list is the header file to be checked,
and the previous list items are header files whose #include lines should precede the header line
being checked for. The optional argument include_quotes must be a two character string, where the
first character denotes the opening quote and the second character denotes the closing quote (both
default to "). Returns 1 on success and 0 on failure.
SConf.CheckFunc(context,, function_name, [header, language])
sconf.CheckFunc(function_name, [header, language])
Checks if the specified C or C++ function is available. function_name is the name of the function
to check for. The optional header argument is a string that will be placed at the top of the test
file that will be compiled to check if the function exists; the default is:
#ifdef __cplusplus
extern "C"
#endif
char function_name();
The optional language argument should be C or C++ and selects the compiler to be used for the check; the
default is "C".
SConf.CheckLib(context, [library, symbol, header, language, autoadd=1])
sconf.CheckLib([library, symbol, header, language, autoadd=1])
Checks if library provides symbol. If the value of autoadd is 1 and the library provides the
specified symbol, appends the library to the LIBS construction environment variable. library may
also be None (the default), in which case symbol is checked with the current LIBS variable, or a
list of library names, in which case each library in the list will be checked for symbol. If
symbol is not set or is None, then SConf.CheckLib() just checks if you can link against the
specified library. The optional language argument should be C or C++ and selects the compiler to
be used for the check; the default is "C". The default value for autoadd is 1. This method
returns 1 on success and 0 on error.
SConf.CheckLibWithHeader(context, library, header, language, [call, autoadd])
sconf.CheckLibWithHeader(library, header, language, [call, autoadd])
In contrast to the SConf.CheckLib call, this call provides a more sophisticated way to check
against libraries. Again, library specifies the library or a list of libraries to check. header
specifies a header to check for. header may be a list, in which case the last item in the list is
the header file to be checked, and the previous list items are header files whose #include lines
should precede the header line being checked for. language may be one of
'C','c','CXX','cxx','C++' and 'c++'. call can be any valid expression (with a trailing ';'). If
call is not set, the default simply checks that you can link against the specified library.
autoadd specifies whether to add the library to the environment (only if the check succeeds). This
method returns 1 on success and 0 on error.
SConf.CheckType(context, type_name, [includes, language])
sconf.CheckType(type_name, [includes, language])
Checks for the existence of a type defined by typedef. type_name specifies the typedef name to
check for. includes is a string containing one or more #include lines that will be inserted into
the program that will be run to test for the existence of the type. The optional language
argument should be C or C++ and selects the compiler to be used for the check; the default is "C".
Example:
sconf.CheckType('foo_type', '#include "my_types.h"', 'C++')
Configure.CheckCC(self)
Checks whether the C compiler (as defined by the CC construction variable) works by trying to
compile a small source file.
By default, SCons only detects if there is a program with the correct name, not if it is a
functioning compiler.
This uses the exact same command than the one used by the object builder for C source file, so it
can be used to detect if a particular compiler flag works or not.
Configure.CheckCXX(self)
Checks whether the C++ compiler (as defined by the CXX construction variable) works by trying to
compile a small source file. By default, SCons only detects if there is a program with the correct
name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for CXX source files, so
it can be used to detect if a particular compiler flag works or not.
Configure.CheckSHCC(self)
Checks whether the C compiler (as defined by the SHCC construction variable) works by trying to
compile a small source file. By default, SCons only detects if there is a program with the correct
name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for C source file, so it
can be used to detect if a particular compiler flag works or not. This does not check whether the
object code can be used to build a shared library, only that the compilation (not link) succeeds.
Configure.CheckSHCXX(self)
Checks whether the C++ compiler (as defined by the SHCXX construction variable) works by trying to
compile a small source file. By default, SCons only detects if there is a program with the correct
name, not if it is a functioning compiler.
This uses the exact same command than the one used by the object builder for CXX source files, so
it can be used to detect if a particular compiler flag works or not. This does not check whether
the object code can be used to build a shared library, only that the compilation (not link)
succeeds.
Example of a typical Configure usage:
env = Environment()
conf = Configure( env )
if not conf.CheckCHeader( 'math.h' ):
print 'We really need math.h!'
Exit(1)
if conf.CheckLibWithHeader( 'qt', 'qapp.h', 'c++',
'QApplication qapp(0,0);' ):
# do stuff for qt - usage, e.g.
conf.env.Append( CPPFLAGS = '-DWITH_QT' )
env = conf.Finish()
SConf.CheckTypeSize(context, type_name, [header, language, expect])
sconf.CheckTypeSize(type_name, [header, language, expect])
Checks for the size of a type defined by typedef. type_name specifies the typedef name to check
for. The optional header argument is a string that will be placed at the top of the test file
that will be compiled to check if the function exists; the default is empty. The optional
language argument should be C or C++ and selects the compiler to be used for the check; the
default is "C". The optional expect argument should be an integer. If this argument is used, the
function will only check whether the type given in type_name has the expected size (in bytes).
For example, CheckTypeSize('short', expect = 2) will return success only if short is two bytes.
SConf.CheckDeclaration(context, symbol, [includes, language])
sconf.CheckDeclaration(symbol, [includes, language])
Checks if the specified symbol is declared. includes is a string containing one or more #include
lines that will be inserted into the program that will be run to test for the existence of the
type. The optional language argument should be C or C++ and selects the compiler to be used for
the check; the default is "C".
SConf.Define(context, symbol, [value, comment])
sconf.Define(symbol, [value, comment])
This function does not check for anything, but defines a preprocessor symbol that will be added to
the configuration header file. It is the equivalent of AC_DEFINE, and defines the symbol name
with the optional value and the optional comment comment.
Examples:
env = Environment()
conf = Configure( env )
# Puts the following line in the config header file:
# #define A_SYMBOL
conf.Define('A_SYMBOL')
# Puts the following line in the config header file:
# #define A_SYMBOL 1
conf.Define('A_SYMBOL', 1)
Be careful about quoting string values, though:
env = Environment()
conf = Configure( env )
# Puts the following line in the config header file:
# #define A_SYMBOL YA
conf.Define('A_SYMBOL', "YA")
# Puts the following line in the config header file:
# #define A_SYMBOL "YA"
conf.Define('A_SYMBOL', '"YA"')
For comment:
env = Environment()
conf = Configure( env )
# Puts the following lines in the config header file:
# /* Set to 1 if you have a symbol */
# #define A_SYMBOL 1
conf.Define('A_SYMBOL', 1, 'Set to 1 if you have a symbol')
You can define your own custom checks. in addition to the predefined checks. These are passed in a
dictionary to the Configure function. This dictionary maps the names of the checks to user defined
Python callables (either Python functions or class instances implementing the __call__ method). The
first argument of the call is always a CheckContext instance followed by the arguments, which must be
supplied by the user of the check. These CheckContext instances define the following methods:
CheckContext.Message(self, text)
Usually called before the check is started. text will be displayed to the user, e.g. 'Checking
for library X...'
CheckContext.Result(self,, res)
Usually called after the check is done. res can be either an integer or a string. In the former
case, 'yes' (res != 0) or 'no' (res == 0) is displayed to the user, in the latter case the given
string is displayed.
CheckContext.TryCompile(self, text, extension)
Checks if a file with the specified extension (e.g. '.c') containing text can be compiled using
the environment's Object builder. Returns 1 on success and 0 on failure.
CheckContext.TryLink(self, text, extension)
Checks, if a file with the specified extension (e.g. '.c') containing text can be compiled using
the environment's Program builder. Returns 1 on success and 0 on failure.
CheckContext.TryRun(self, text, extension)
Checks, if a file with the specified extension (e.g. '.c') containing text can be compiled using
the environment's Program builder. On success, the program is run. If the program executes
successfully (that is, its return status is 0), a tuple (1, outputStr) is returned, where
outputStr is the standard output of the program. If the program fails execution (its return
status is non-zero), then (0, '') is returned.
CheckContext.TryAction(self, action, [text, extension])
Checks if the specified action with an optional source file (contents text , extension extension =
'' ) can be executed. action may be anything which can be converted to a scons Action. On
success, (1, outputStr) is returned, where outputStr is the content of the target file. On
failure (0, '') is returned.
CheckContext.TryBuild(self, builder, [text, extension])
Low level implementation for testing specific builds; the methods above are based on this method.
Given the Builder instance builder and the optional text of a source file with optional extension,
this method returns 1 on success and 0 on failure. In addition, self.lastTarget is set to the
build target node, if the build was successful.
Example for implementing and using custom tests:
def CheckQt(context, qtdir):
context.Message( 'Checking for qt ...' )
lastLIBS = context.env['LIBS']
lastLIBPATH = context.env['LIBPATH']
lastCPPPATH= context.env['CPPPATH']
context.env.Append(LIBS = 'qt', LIBPATH = qtdir + '/lib', CPPPATH = qtdir + '/include' )
ret = context.TryLink("""
#include <qapp.h>
int main(int argc, char **argv) {
QApplication qapp(argc, argv);
return 0;
}
""")
if not ret:
context.env.Replace(LIBS = lastLIBS, LIBPATH=lastLIBPATH, CPPPATH=lastCPPPATH)
context.Result( ret )
return ret
env = Environment()
conf = Configure( env, custom_tests = { 'CheckQt' : CheckQt } )
if not conf.CheckQt('/usr/lib/qt'):
print 'We really need qt!'
Exit(1)
env = conf.Finish()
Command-Line Construction Variables
Often when building software, some variables must be specified at build time. For example, libraries
needed for the build may be in non-standard locations, or site-specific compiler options may need to be
passed to the compiler. scons provides a Variables object to support overriding construction variables
on the command line:
$ scons VARIABLE=foo
The variable values can also be specified in a text-based SConscript file. To create a Variables object,
call the Variables() function:
Variables([files], [args])
This creates a Variables object that will read construction variables from the file or list of
filenames specified in files. If no files are specified, or the files argument is None, then no
files will be read. The optional argument args is a dictionary of values that will override
anything read from the specified files; it is primarily intended to be passed the ARGUMENTS
dictionary that holds variables specified on the command line. Example:
vars = Variables('custom.py')
vars = Variables('overrides.py', ARGUMENTS)
vars = Variables(None, {FOO:'expansion', BAR:7})
Variables objects have the following methods:
Add(key, [help, default, validator, converter])
This adds a customizable construction variable to the Variables object. key is the name of the
variable. help is the help text for the variable. default is the default value of the variable;
if the default value is None and there is no explicit value specified, the construction variable
will not be added to the construction environment. validator is called to validate the value of
the variable, and should take three arguments: key, value, and environment. The recommended way
to handle an invalid value is to raise an exception (see example below). converter is called to
convert the value before putting it in the environment, and should take either a value, or the
value and environment, as parameters. The converter must return a value, which will be converted
into a string before being validated by the validator (if any) and then added to the environment.
Examples:
vars.Add('CC', 'The C compiler')
def validate_color(key, val, env):
if not val in ['red', 'blue', 'yellow']:
raise Exception("Invalid color value '%s'" % val)
vars.Add('COLOR', validator=valid_color)
AddVariables(list)
A wrapper script that adds multiple customizable construction variables to a Variables object.
list is a list of tuple or list objects that contain the arguments for an individual call to the
Add method.
opt.AddVariables(
('debug', '', 0),
('CC', 'The C compiler'),
('VALIDATE', 'An option for testing validation',
'notset', validator, None),
)
Update(env, [args])
This updates a construction environment env with the customized construction variables. Any
specified variables that are not configured for the Variables object will be saved and may be
retrieved with the UnknownVariables() method, below.
Normally this method is not called directly, but is called indirectly by passing the Variables
object to the Environment() function:
env = Environment(variables=vars)
The text file(s) that were specified when the Variables object was created are executed as Python
scripts, and the values of (global) Python variables set in the file are added to the construction
environment.
Example:
CC = 'my_cc'
UnknownVariables()
Returns a dictionary containing any variables that were specified either in the files or the
dictionary with which the Variables object was initialized, but for which the Variables object was
not configured.
env = Environment(variables=vars)
for key, value in vars.UnknownVariables():
print "unknown variable: %s=%s" % (key, value)
Save(filename, env)
This saves the currently set variables into a script file named filename that can be used on the
next invocation to automatically load the current settings. This method combined with the
Variables method can be used to support caching of variables between runs.
env = Environment()
vars = Variables(['variables.cache', 'custom.py'])
vars.Add(...)
vars.Update(env)
vars.Save('variables.cache', env)
GenerateHelpText(env, [sort])
This generates help text documenting the customizable construction variables suitable to passing
in to the Help() function. env is the construction environment that will be used to get the
actual values of customizable variables. Calling with an optional sort function will cause the
output to be sorted by the specified argument. The specific sort function should take two
arguments and return -1, 0 or 1 (like the standard Python cmp function).
Help(vars.GenerateHelpText(env))
Help(vars.GenerateHelpText(env, sort=cmp))
FormatVariableHelpText(env, opt, help, default, actual)
This method returns a formatted string containing the printable help text for one option. It is
normally not called directly, but is called by the GenerateHelpText() method to create the
returned help text. It may be overridden with your own function that takes the arguments
specified above and returns a string of help text formatted to your liking. Note that the
GenerateHelpText() will not put any blank lines or extra characters in between the entries, so you
must add those characters to the returned string if you want the entries separated.
def my_format(env, opt, help, default, actual):
fmt = "97s: default=%s actual=%s (%s)0
return fmt % (opt, default. actual, help)
vars.FormatVariableHelpText = my_format
To make it more convenient to work with customizable Variables, scons provides a number of functions that
make it easy to set up various types of Variables:
BoolVariable(key, help, default)
Return a tuple of arguments to set up a Boolean option. The option will use the specified name
key, have a default value of default, and display the specified help text. The option will
interpret the values y, yes, t, true, 1, on and all as true, and the values n, no, f, false, 0,
off and none as false.
EnumVariable(key, help, default, allowed_values, [map, ignorecase])
Return a tuple of arguments to set up an option whose value may be one of a specified list of
legal enumerated values. The option will use the specified name key, have a default value of
default, and display the specified help text. The option will only support those values in the
allowed_values list. The optional map argument is a dictionary that can be used to convert input
values into specific legal values in the allowed_values list. If the value of ignore_case is 0
(the default), then the values are case-sensitive. If the value of ignore_case is 1, then values
will be matched case-insensitive. If the value of ignore_case is 1, then values will be matched
case-insensitive, and all input values will be converted to lower case.
ListVariable(key, help, default, names, [,map])
Return a tuple of arguments to set up an option whose value may be one or more of a specified list
of legal enumerated values. The option will use the specified name key, have a default value of
default, and display the specified help text. The option will only support the values all, none,
or the values in the names list. More than one value may be specified, with all values separated
by commas. The default may be a string of comma-separated default values, or a list of the
default values. The optional map argument is a dictionary that can be used to convert input
values into specific legal values in the names list.
PackageVariable(key, help, default)
Return a tuple of arguments to set up an option whose value is a path name of a package that may
be enabled, disabled or given an explicit path name. The option will use the specified name key,
have a default value of default, and display the specified help text. The option will support the
values yes, true, on, enable or search, in which case the specified default will be used, or the
option may be set to an arbitrary string (typically the path name to a package that is being
enabled). The option will also support the values no, false, off or disable to disable use of the
specified option.
PathVariable(key, help, default, [validator])
Return a tuple of arguments to set up an option whose value is expected to be a path name. The
option will use the specified name key, have a default value of default, and display the specified
help text. An additional validator may be specified that will be called to verify that the
specified path is acceptable. SCons supplies the following ready-made validators:
PathVariable.PathExists (the default), which verifies that the specified path exists;
PathVariable.PathIsFile, which verifies that the specified path is an existing file;
PathVariable.PathIsDir, which verifies that the specified path is an existing directory;
PathVariable.PathIsDirCreate, which verifies that the specified path is a directory and will
create the specified directory if the path does not exist; and PathVariable.PathAccept, which
simply accepts the specific path name argument without validation, and which is suitable if you
want your users to be able to specify a directory path that will be created as part of the build
process, for example. You may supply your own validator function, which must take three arguments
(key, the name of the variable to be set; val, the specified value being checked; and env, the
construction environment) and should raise an exception if the specified value is not acceptable.
These functions make it convenient to create a number of variables with consistent behavior in a single
call to the AddVariables method:
vars.AddVariables(
BoolVariable('warnings', 'compilation with -Wall and similiar', 1),
EnumVariable('debug', 'debug output and symbols', 'no'
allowed_values=('yes', 'no', 'full'),
map={}, ignorecase=0), # case sensitive
ListVariable('shared',
'libraries to build as shared libraries',
'all',
names = list_of_libs),
PackageVariable('x11',
'use X11 installed here (yes = search some places)',
'yes'),
PathVariable('qtdir', 'where the root of Qt is installed', qtdir),
PathVariable('foopath', 'where the foo library is installed', foopath,
PathVariable.PathIsDir),
)
File and Directory Nodes
The File() and Dir() functions return File and Dir Nodes, respectively. python objects, respectively.
Those objects have several user-visible attributes and methods that are often useful:
path The build path of the given file or directory. This path is relative to the top-level directory
(where the SConstruct file is found). The build path is the same as the source path if
variant_dir is not being used.
abspath
The absolute build path of the given file or directory.
srcnode()
The srcnode() method returns another File or Dir object representing the source path of the given
File or Dir. The
# Get the current build dir's path, relative to top.
Dir('.').path
# Current dir's absolute path
Dir('.').abspath
# Next line is always '.', because it is the top dir's path relative to itself.
Dir('#.').path
File('foo.c').srcnode().path # source path of the given source file.
# Builders also return File objects:
foo = env.Program('foo.c')
print "foo will be built in %s"%foo.path
A Dir Node or File Node can also be used to create file and subdirectory Nodes relative to the generating
Node. A Dir Node will place the new Nodes within the directory it represents. A File node will place
the new Nodes within its parent directory (that is, "beside" the file in question). If d is a Dir
(directory) Node and f is a File (file) Node, then these methods are available:
d.Dir(name)
Returns a directory Node for a subdirectory of d named name.
d.File(name)
Returns a file Node for a file within d named name.
d.Entry(name)
Returns an unresolved Node within d named name.
f.Dir(name)
Returns a directory named name within the parent directory of f.
f.File(name)
Returns a file named name within the parent directory of f.
f.Entry(name)
Returns an unresolved Node named name within the parent directory of f.
For example:
# Get a Node for a file within a directory
incl = Dir('include')
f = incl.File('header.h')
# Get a Node for a subdirectory within a directory
dist = Dir('project-3.2.1)
src = dist.Dir('src')
# Get a Node for a file in the same directory
cfile = File('sample.c')
hfile = cfile.File('sample.h')
# Combined example
docs = Dir('docs')
html = docs.Dir('html')
index = html.File('index.html')
css = index.File('app.css')
EXTENDING SCONS
Builder Objects
scons can be extended to build different types of targets by adding new Builder objects to a construction
environment. In general, you should only need to add a new Builder object when you want to build a new
type of file or other external target. If you just want to invoke a different compiler or other tool to
build a Program, Object, Library, or any other type of output file for which scons already has an
existing Builder, it is generally much easier to use those existing Builders in a construction
environment that sets the appropriate construction variables (CC, LINK, etc.).
Builder objects are created using the Builder function. The Builder function accepts the following
arguments:
action The command line string used to build the target from the source. action can also be: a list of
strings representing the command to be executed and its arguments (suitable for enclosing white
space in an argument), a dictionary mapping source file name suffixes to any combination of
command line strings (if the builder should accept multiple source file extensions), a Python
function; an Action object (see the next section); or a list of any of the above.
An action function takes three arguments: source - a list of source nodes, target - a list of
target nodes, env - the construction environment.
prefix The prefix that will be prepended to the target file name. This may be specified as a:
* string,
* callable object - a function or other callable that takes two arguments (a construction
environment and a list of sources) and returns a prefix,
* dictionary - specifies a mapping from a specific source suffix (of the first source
specified) to a corresponding target prefix. Both the source suffix and target prefix
specifications may use environment variable substitution, and the target prefix (the
'value' entries in the dictionary) may also be a callable object. The default target
prefix may be indicated by a dictionary entry with a key value of None.
b = Builder("build_it < $SOURCE > $TARGET",
prefix = "file-")
def gen_prefix(env, sources):
return "file-" + env['PLATFORM'] + '-'
b = Builder("build_it < $SOURCE > $TARGET",
prefix = gen_prefix)
b = Builder("build_it < $SOURCE > $TARGET",
suffix = { None: "file-",
"$SRC_SFX_A": gen_prefix })
suffix The suffix that will be appended to the target file name. This may be specified in the same
manner as the prefix above. If the suffix is a string, then scons will append a '.' to the
beginning of the suffix if it's not already there. The string returned by callable object (or
obtained from the dictionary) is untouched and must append its own '.' to the beginning if one is
desired.
b = Builder("build_it < $SOURCE > $TARGET"
suffix = "-file")
def gen_suffix(env, sources):
return "." + env['PLATFORM'] + "-file"
b = Builder("build_it < $SOURCE > $TARGET",
suffix = gen_suffix)
b = Builder("build_it < $SOURCE > $TARGET",
suffix = { None: ".sfx1",
"$SRC_SFX_A": gen_suffix })
ensure_suffix
When set to any true value, causes scons to add the target suffix specified by the suffix keyword
to any target strings that have a different suffix. (The default behavior is to leave untouched
any target file name that looks like it already has any suffix.)
b1 = Builder("build_it < $SOURCE > $TARGET"
suffix = ".out")
b2 = Builder("build_it < $SOURCE > $TARGET"
suffix = ".out",
ensure_suffix)
env = Environment()
env['BUILDERS']['B1'] = b1
env['BUILDERS']['B2'] = b2
# Builds "foo.txt" because ensure_suffix is not set.
env.B1('foo.txt', 'foo.in')
# Builds "bar.txt.out" because ensure_suffix is set.
env.B2('bar.txt', 'bar.in')
src_suffix
The expected source file name suffix. This may be a string or a list of strings.
target_scanner
A Scanner object that will be invoked to find implicit dependencies for this target file. This
keyword argument should be used for Scanner objects that find implicit dependencies based only on
the target file and the construction environment, not for implicit dependencies based on source
files. (See the section "Scanner Objects" below, for information about creating Scanner objects.)
source_scanner
A Scanner object that will be invoked to find implicit dependencies in any source files used to
build this target file. This is where you would specify a scanner to find things like #include
lines in source files. The pre-built DirScanner Scanner object may be used to indicate that this
Builder should scan directory trees for on-disk changes to files that scons does not know about
from other Builder or function calls. (See the section "Scanner Objects" below, for information
about creating your own Scanner objects.)
target_factory
A factory function that the Builder will use to turn any targets specified as strings into SCons
Nodes. By default, SCons assumes that all targets are files. Other useful target_factory values
include Dir, for when a Builder creates a directory target, and Entry, for when a Builder can
create either a file or directory target.
Example:
MakeDirectoryBuilder = Builder(action=my_mkdir, target_factory=Dir)
env = Environment()
env.Append(BUILDERS = {'MakeDirectory':MakeDirectoryBuilder})
env.MakeDirectory('new_directory', [])
Note that the call to the MakeDirectory Builder needs to specify an empty source list to make the
string represent the builder's target; without that, it would assume the argument is the source,
and would try to deduce the target name from it, which in the absence of an automatically-added
prefix or suffix would lead to a matching target and source name and a circular dependency.
source_factory
A factory function that the Builder will use to turn any sources specified as strings into SCons
Nodes. By default, SCons assumes that all source are files. Other useful source_factory values
include Dir, for when a Builder uses a directory as a source, and Entry, for when a Builder can
use files or directories (or both) as sources.
Example:
CollectBuilder = Builder(action=my_mkdir, source_factory=Entry)
env = Environment()
env.Append(BUILDERS = {'Collect':CollectBuilder})
env.Collect('archive', ['directory_name', 'file_name'])
emitter
A function or list of functions to manipulate the target and source lists before dependencies are
established and the target(s) are actually built. emitter can also be a string containing a
construction variable to expand to an emitter function or list of functions, or a dictionary
mapping source file suffixes to emitter functions. (Only the suffix of the first source file is
used to select the actual emitter function from an emitter dictionary.)
An emitter function takes three arguments: source - a list of source nodes, target - a list of
target nodes, env - the construction environment. An emitter must return a tuple containing two
lists, the list of targets to be built by this builder, and the list of sources for this builder.
Example:
def e(target, source, env):
return (target + ['foo.foo'], source + ['foo.src'])
# Simple association of an emitter function with a Builder.
b = Builder("my_build < $TARGET > $SOURCE",
emitter = e)
def e2(target, source, env):
return (target + ['bar.foo'], source + ['bar.src'])
# Simple association of a list of emitter functions with a Builder.
b = Builder("my_build < $TARGET > $SOURCE",
emitter = [e, e2])
# Calling an emitter function through a construction variable.
env = Environment(MY_EMITTER = e)
b = Builder("my_build < $TARGET > $SOURCE",
emitter = '$MY_EMITTER')
# Calling a list of emitter functions through a construction variable.
env = Environment(EMITTER_LIST = [e, e2])
b = Builder("my_build < $TARGET > $SOURCE",
emitter = '$EMITTER_LIST')
# Associating multiple emitters with different file
# suffixes using a dictionary.
def e_suf1(target, source, env):
return (target + ['another_target_file'], source)
def e_suf2(target, source, env):
return (target, source + ['another_source_file'])
b = Builder("my_build < $TARGET > $SOURCE",
emitter = {'.suf1' : e_suf1,
'.suf2' : e_suf2})
multi Specifies whether this builder is allowed to be called multiple times for the same target file(s).
The default is 0, which means the builder can not be called multiple times for the same target
file(s). Calling a builder multiple times for the same target simply adds additional source files
to the target; it is not allowed to change the environment associated with the target, specify
addition environment overrides, or associate a different builder with the target.
env A construction environment that can be used to fetch source code using this Builder. (Note that
this environment is not used for normal builds of normal target files, which use the environment
that was used to call the Builder for the target file.)
generator
A function that returns a list of actions that will be executed to build the target(s) from the
source(s). The returned action(s) may be an Action object, or anything that can be converted into
an Action object (see the next section).
The generator function takes four arguments: source - a list of source nodes, target - a list of
target nodes, env - the construction environment, for_signature - a Boolean value that specifies
whether the generator is being called for generating a build signature (as opposed to actually
executing the command). Example:
def g(source, target, env, for_signature):
return [["gcc", "-c", "-o"] + target + source]
b = Builder(generator=g)
The generator and action arguments must not both be used for the same Builder.
src_builder
Specifies a builder to use when a source file name suffix does not match any of the suffixes of
the builder. Using this argument produces a multi-stage builder.
single_source
Specifies that this builder expects exactly one source file per call. Giving more than one source
file without target files results in implicitely calling the builder multiple times (once for each
source given). Giving multiple source files together with target files results in a UserError
exception.
The generator and action arguments must not both be used for the same Builder.
source_ext_match
When the specified action argument is a dictionary, the default behavior when a builder is passed
multiple source files is to make sure that the extensions of all the source files match. If it is
legal for this builder to be called with a list of source files with different extensions, this
check can be suppressed by setting source_ext_match to None or some other non-true value. When
source_ext_match is disable, scons will use the suffix of the first specified source file to
select the appropriate action from the action dictionary.
In the following example, the setting of source_ext_match prevents scons from exiting with an
error due to the mismatched suffixes of foo.in and foo.extra.
b = Builder(action={'.in' : 'build $SOURCES > $TARGET'},
source_ext_match = None)
env = Environment(BUILDERS = {'MyBuild':b})
env.MyBuild('foo.out', ['foo.in', 'foo.extra'])
env A construction environment that can be used to fetch source code using this Builder. (Note that
this environment is not used for normal builds of normal target files, which use the environment
that was used to call the Builder for the target file.)
b = Builder(action="build < $SOURCE > $TARGET")
env = Environment(BUILDERS = {'MyBuild' : b})
env.MyBuild('foo.out', 'foo.in', my_arg = 'xyzzy')
chdir A directory from which scons will execute the action(s) specified for this Builder. If the chdir
argument is a string or a directory Node, scons will change to the specified directory. If the
chdir is not a string or Node and is non-zero, then scons will change to the target file's
directory.
Note that scons will not automatically modify its expansion of construction variables like $TARGET
and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be
relative to the top-level SConstruct directory, and consequently incorrect relative to the chdir
directory. Builders created using chdir keyword argument, will need to use construction variable
expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets
and source.
b = Builder(action="build < ${SOURCE.file} > ${TARGET.file}",
chdir=1)
env = Environment(BUILDERS = {'MyBuild' : b})
env.MyBuild('sub/dir/foo.out', 'sub/dir/foo.in')
WARNING: Python only keeps one current directory location for all of the threads. This means that use of
the chdir argument will not work with the SCons -j option, because individual worker threads spawned by
SCons interfere with each other when they start changing directory.
Any additional keyword arguments supplied when a Builder object is created (that is, when the Builder()
function is called) will be set in the executing construction environment when the Builder object is
called. The canonical example here would be to set a construction variable to the repository of a source
code system.
Any additional keyword arguments supplied when a Builder object is called will only be associated with
the target created by that particular Builder call (and any other files built as a result of the call).
These extra keyword arguments are passed to the following functions: command generator functions,
function Actions, and emitter functions.
Action Objects
The Builder() function will turn its action keyword argument into an appropriate internal Action object.
You can also explicity create Action objects using the Action() global function, which can then be passed
to the Builder() function. This can be used to configure an Action object more flexibly, or it may
simply be more efficient than letting each separate Builder object create a separate Action when multiple
Builder objects need to do the same thing.
The Action() global function returns an appropriate object for the action represented by the type of the
first argument:
Action If the first argument is already an Action object, the object is simply returned.
String If the first argument is a string, a command-line Action is returned. Note that the command-line
string may be preceded by an @ (at-sign) to suppress printing of the specified command line, or by
a - (hyphen) to ignore the exit status from the specified command:
Action('$CC -c -o $TARGET $SOURCES')
# Doesn't print the line being executed.
Action('@build $TARGET $SOURCES')
# Ignores return value
Action('-build $TARGET $SOURCES')
List If the first argument is a list, then a list of Action objects is returned. An Action object is
created as necessary for each element in the list. If an element within the list is itself a
list, the internal list is the command and arguments to be executed via the command line. This
allows white space to be enclosed in an argument by defining a command in a list within a list:
Action([['cc', '-c', '-DWHITE SPACE', '-o', '$TARGET', '$SOURCES']])
Function
If the first argument is a Python function, a function Action is returned. The Python function
must take three keyword arguments, target (a Node object representing the target file), source (a
Node object representing the source file) and env (the construction environment used for building
the target file). The target and source arguments may be lists of Node objects if there is more
than one target file or source file. The actual target and source file name(s) may be retrieved
from their Node objects via the built-in Python str() function:
target_file_name = str(target)
source_file_names = map(lambda x: str(x), source)
The function should return 0 or None to indicate a successful build of the target file(s). The
function may raise an exception or return a non-zero exit status to indicate an unsuccessful
build.
def build_it(target = None, source = None, env = None):
# build the target from the source
return 0
a = Action(build_it)
If the action argument is not one of the above, None is returned.
The second argument is optional and is used to define the output which is printed when the Action is
actually performed. In the absence of this parameter, or if it's an empty string, a default output
depending on the type of the action is used. For example, a command-line action will print the executed
command. The argument must be either a Python function or a string.
In the first case, it's a function that returns a string to be printed to describe the action being
executed. The function may also be specified by the strfunction= keyword argument. Like a function to
build a file, this function must take three keyword arguments: target (a Node object representing the
target file), source (a Node object representing the source file) and env (a construction environment).
The target and source arguments may be lists of Node objects if there is more than one target file or
source file.
In the second case, you provide the string itself. The string may also be specified by the cmdstr=
keyword argument. The string typically contains variables, notably $TARGET(S) and $SOURCE(S), or
consists of just a single variable, which is optionally defined somewhere else. SCons itself heavily
uses the latter variant.
Examples:
def build_it(target, source, env):
# build the target from the source
return 0
def string_it(target, source, env):
return "building '%s' from '%s'" % (target[0], source[0])
# Use a positional argument.
f = Action(build_it, string_it)
s = Action(build_it, "building '$TARGET' from '$SOURCE'")
# Alternatively, use a keyword argument.
f = Action(build_it, strfunction=string_it)
s = Action(build_it, cmdstr="building '$TARGET' from '$SOURCE'")
# You can provide a configurable variable.
l = Action(build_it, '$STRINGIT')
The third and succeeding arguments, if present, may either be a construction variable or a list of
construction variables whose values will be included in the signature of the Action when deciding whether
a target should be rebuilt because the action changed. The variables may also be specified by a varlist=
keyword parameter; if both are present, they are combined. This is necessary whenever you want a target
to be rebuilt when a specific construction variable changes. This is not often needed for a string
action, as the expanded variables will normally be part of the command line, but may be needed if a
Python function action uses the value of a construction variable when generating the command line.
def build_it(target, source, env):
# build the target from the 'XXX' construction variable
open(target[0], 'w').write(env['XXX'])
return 0
# Use positional arguments.
a = Action(build_it, '$STRINGIT', ['XXX'])
# Alternatively, use a keyword argument.
a = Action(build_it, varlist=['XXX'])
The Action() global function can be passed the following optional keyword arguments to modify the Action
object's behavior:
chdir The chdir keyword argument specifies that scons will execute the action after changing to
the specified directory. If the chdir argument is a string or a directory Node, scons will change
to the specified directory. If the chdir argument is not a string or Node and is non-zero, then
scons will change to the target file's directory.
Note that scons will not automatically modify its expansion of construction variables like $TARGET
and $SOURCE when using the chdir keyword argument--that is, the expanded file names will still be
relative to the top-level SConstruct directory, and consequently incorrect relative to the chdir
directory. Builders created using chdir keyword argument, will need to use construction variable
expansions like ${TARGET.file} and ${SOURCE.file} to use just the filename portion of the targets
and source.
a = Action("build < ${SOURCE.file} > ${TARGET.file}",
chdir=1)
exitstatfunc The Action() global function also takes an exitstatfunc keyword argument which
specifies a function that is passed the exit status (or return value) from the specified action
and can return an arbitrary or modified value. This can be used, for example, to specify that an
Action object's return value should be ignored under special conditions and SCons should,
therefore, consider that the action always suceeds:
def always_succeed(s):
# Always return 0, which indicates success.
return 0
a = Action("build < ${SOURCE.file} > ${TARGET.file}",
exitstatfunc=always_succeed)
batch_key The batch_key keyword argument can be used to specify that the Action can create
multiple target files by processing multiple independent source files simultaneously. (The
canonical example is "batch compilation" of multiple object files by passing multiple source files
to a single invocation of a compiler such as Microsoft's Visual C / C++ compiler.) If the
batch_key argument is any non-False, non-callable Python value, the configured Action object will
cause scons to collect all targets built with the Action object and configured with the same
construction environment into single invocations of the Action object's command line or function.
Command lines will typically want to use the CHANGED_SOURCES construction variable (and possibly
CHANGED_TARGETS as well) to only pass to the command line those sources that have actually changed
since their targets were built.
Example:
a = Action('build $CHANGED_SOURCES', batch_key=True)
The batch_key argument may also be a callable function that returns a key that will be used to identify
different "batches" of target files to be collected for batch building. A batch_key function must take
the following arguments:
action The action object.
env The construction environment configured for the target.
target The list of targets for a particular configured action.
source The list of source for a particular configured action.
The returned key should typically be a tuple of values derived from the arguments, using any
appropriate logic to decide how multiple invocations should be batched. For example, a batch_key
function may decide to return the value of a specific construction variable from the env argument
which will cause scons to batch-build targets with matching values of that variable, or perhaps
return the id() of the entire construction environment, in which case scons will batch-build all
targets configured with the same construction environment. Returning None indicates that the
particular target should not be part of any batched build, but instead will be built by a separate
invocation of action's command or function. Example:
def batch_key(action, env, target, source):
tdir = target[0].dir
if tdir.name == 'special':
# Don't batch-build any target
# in the special/ subdirectory.
return None
return (id(action), id(env), tdir)
a = Action('build $CHANGED_SOURCES', batch_key=batch_key)
Miscellaneous Action Functions
scons supplies a number of functions that arrange for various common file and directory manipulations to
be performed. These are similar in concept to "tasks" in the Ant build tool, although the implementation
is slightly different. These functions do not actually perform the specified action at the time the
function is called, but instead return an Action object that can be executed at the appropriate time.
(In Object-Oriented terminology, these are actually Action Factory functions that return Action objects.)
In practice, there are two natural ways that these Action Functions are intended to be used.
First, if you need to perform the action at the time the SConscript file is being read, you can use the
Execute global function to do so:
Execute(Touch('file'))
Second, you can use these functions to supply Actions in a list for use by the Command method. This can
allow you to perform more complicated sequences of file manipulation without relying on platform-specific
external commands: that
env = Environment(TMPBUILD = '/tmp/builddir')
env.Command('foo.out', 'foo.in',
[Mkdir('$TMPBUILD'),
Copy('$TMPBUILD', '${SOURCE.dir}'),
"cd $TMPBUILD && make",
Delete('$TMPBUILD')])
Chmod(dest, mode)
Returns an Action object that changes the permissions on the specified dest file or directory to
the specified mode. Examples:
Execute(Chmod('file', 0755))
env.Command('foo.out', 'foo.in',
[Copy('$TARGET', '$SOURCE'),
Chmod('$TARGET', 0755)])
Copy(dest, src)
Returns an Action object that will copy the src source file or directory to the dest destination
file or directory. Examples:
Execute(Copy('foo.output', 'foo.input'))
env.Command('bar.out', 'bar.in',
Copy('$TARGET', '$SOURCE'))
Delete(entry, [must_exist])
Returns an Action that deletes the specified entry, which may be a file or a directory tree. If a
directory is specified, the entire directory tree will be removed. If the must_exist flag is set,
then a Python error will be thrown if the specified entry does not exist; the default is
must_exist=0, that is, the Action will silently do nothing if the entry does not exist. Examples:
Execute(Delete('/tmp/buildroot'))
env.Command('foo.out', 'foo.in',
[Delete('${TARGET.dir}'),
MyBuildAction])
Execute(Delete('file_that_must_exist', must_exist=1))
Mkdir(dir)
Returns an Action that creates the specified directory dir . Examples:
Execute(Mkdir('/tmp/outputdir'))
env.Command('foo.out', 'foo.in',
[Mkdir('/tmp/builddir'),
Copy('/tmp/builddir/foo.in', '$SOURCE'),
"cd /tmp/builddir && make",
Copy('$TARGET', '/tmp/builddir/foo.out')])
Move(dest, src)
Returns an Action that moves the specified src file or directory to the specified dest file or
directory. Examples:
Execute(Move('file.destination', 'file.source'))
env.Command('output_file', 'input_file',
[MyBuildAction,
Move('$TARGET', 'file_created_by_MyBuildAction')])
Touch(file)
Returns an Action that updates the modification time on the specified file. Examples:
Execute(Touch('file_to_be_touched'))
env.Command('marker', 'input_file',
[MyBuildAction,
Touch('$TARGET')])
Variable Substitution
Before executing a command, scons performs construction variable interpolation on the strings that make
up the command line of builders. Variables are introduced by a $ prefix. Besides construction
variables, scons provides the following variables for each command execution:
CHANGED_SOURCES
The file names of all sources of the build command that have changed since the target was last
built.
CHANGED_TARGETS
The file names of all targets that would be built from sources that have changed since the target
was last built.
SOURCE The file name of the source of the build command, or the file name of the first source if multiple
sources are being built.
SOURCES
The file names of the sources of the build command.
TARGET The file name of the target being built, or the file name of the first target if multiple targets
are being built.
TARGETS
The file names of all targets being built.
UNCHANGED_SOURCES
The file names of all sources of the build command that have not changed since the target was last
built.
UNCHANGED_TARGETS
The file names of all targets that would be built from sources that have not changed since the
target was last built.
(Note that the above variables are reserved and may not be set in a construction environment.)
For example, given the construction variable CC='cc', targets=['foo'], and sources=['foo.c', 'bar.c']:
action='$CC -c -o $TARGET $SOURCES'
would produce the command line:
cc -c -o foo foo.c bar.c
Variable names may be surrounded by curly braces ({}) to separate the name from the trailing characters.
Within the curly braces, a variable name may have a Python slice subscript appended to select one or more
items from a list. In the previous example, the string:
${SOURCES[1]}
would produce:
bar.c
Additionally, a variable name may have the following special modifiers appended within the enclosing
curly braces to modify the interpolated string:
base The base path of the file name, including the directory path but excluding any suffix.
dir The name of the directory in which the file exists.
file The file name, minus any directory portion.
filebase
Just the basename of the file, minus any suffix and minus the directory.
suffix Just the file suffix.
abspath
The absolute path name of the file.
posix The POSIX form of the path, with directories separated by / (forward slashes) not backslashes.
This is sometimes necessary on Windows systems when a path references a file on other (POSIX)
systems.
srcpath
The directory and file name to the source file linked to this file through VariantDir(). If this
file isn't linked, it just returns the directory and filename unchanged.
srcdir The directory containing the source file linked to this file through VariantDir(). If this file
isn't linked, it just returns the directory part of the filename.
rsrcpath
The directory and file name to the source file linked to this file through VariantDir(). If the
file does not exist locally but exists in a Repository, the path in the Repository is returned.
If this file isn't linked, it just returns the directory and filename unchanged.
rsrcdir
The Repository directory containing the source file linked to this file through VariantDir(). If
this file isn't linked, it just returns the directory part of the filename.
For example, the specified target will expand as follows for the corresponding modifiers:
$TARGET => sub/dir/file.x
${TARGET.base} => sub/dir/file
${TARGET.dir} => sub/dir
${TARGET.file} => file.x
${TARGET.filebase} => file
${TARGET.suffix} => .x
${TARGET.abspath} => /top/dir/sub/dir/file.x
SConscript('src/SConscript', variant_dir='sub/dir')
$SOURCE => sub/dir/file.x
${SOURCE.srcpath} => src/file.x
${SOURCE.srcdir} => src
Repository('/usr/repository')
$SOURCE => sub/dir/file.x
${SOURCE.rsrcpath} => /usr/repository/src/file.x
${SOURCE.rsrcdir} => /usr/repository/src
Note that curly braces braces may also be used to enclose arbitrary Python code to be evaluated. (In
fact, this is how the above modifiers are substituted, they are simply attributes of the Python objects
that represent TARGET, SOURCES, etc.) See the section "Python Code Substitution" below, for more
thorough examples of how this can be used.
Lastly, a variable name may be a callable Python function associated with a construction variable in the
environment. The function should take four arguments: target - a list of target nodes, source - a list
of source nodes, env - the construction environment, for_signature - a Boolean value that specifies
whether the function is being called for generating a build signature. SCons will insert whatever the
called function returns into the expanded string:
def foo(target, source, env, for_signature):
return "bar"
# Will expand $BAR to "bar baz"
env=Environment(FOO=foo, BAR="$FOO baz")
You can use this feature to pass arguments to a Python function by creating a callable class that stores
one or more arguments in an object, and then uses them when the __call__() method is called. Note that
in this case, the entire variable expansion must be enclosed by curly braces so that the arguments will
be associated with the instantiation of the class:
class foo(object):
def __init__(self, arg):
self.arg = arg
def __call__(self, target, source, env, for_signature):
return self.arg + " bar"
# Will expand $BAR to "my argument bar baz"
env=Environment(FOO=foo, BAR="${FOO('my argument')} baz")
The special pseudo-variables $( and $) may be used to surround parts of a command line that may change
without causing a rebuild--that is, which are not included in the signature of target files built with
this command. All text between $( and $) will be removed from the command line before it is added to
file signatures, and the $( and $) will be removed before the command is executed. For example, the
command line:
echo Last build occurred $( $TODAY $). > $TARGET
would execute the command:
echo Last build occurred $TODAY. > $TARGET
but the command signature added to any target files would be:
echo Last build occurred . > $TARGET
Python Code Substitution
Any python code within ${-} pairs gets evaluated by python 'eval', with the python globals set to the
current environment's set of construction variables. So in the following case:
env['COND'] = 0
env.Command('foo.out', 'foo.in',
'''echo ${COND==1 and 'FOO' or 'BAR'} > $TARGET''')
the command executed will be either
echo FOO > foo.out
or
echo BAR > foo.out
according to the current value of env['COND'] when the command is executed. The evaluation occurs when
the target is being built, not when the SConscript is being read. So if env['COND'] is changed later in
the SConscript, the final value will be used.
Here's a more interesting example. Note that all of COND, FOO, and BAR are environment variables, and
their values are substituted into the final command. FOO is a list, so its elements are interpolated
separated by spaces.
env=Environment()
env['COND'] = 0
env['FOO'] = ['foo1', 'foo2']
env['BAR'] = 'barbar'
env.Command('foo.out', 'foo.in',
'echo ${COND==1 and FOO or BAR} > $TARGET')
# Will execute this:
# echo foo1 foo2 > foo.out
SCons uses the following rules when converting construction variables into command lines:
String When the value is a string it is interpreted as a space delimited list of command line arguments.
List When the value is a list it is interpreted as a list of command line arguments. Each element of
the list is converted to a string.
Other Anything that is not a list or string is converted to a string and interpreted as a single command
line argument.
Newline
Newline characters (\n) delimit lines. The newline parsing is done after all other parsing, so it
is not possible for arguments (e.g. file names) to contain embedded newline characters. This
limitation will likely go away in a future version of SCons.
Scanner Objects
You can use the Scanner function to define objects to scan new file types for implicit dependencies. The
Scanner function accepts the following arguments:
function
This can be either: 1) a Python function that will process the Node (file) and return a list of
File Nodes representing the implicit dependencies (file names) found in the contents; or: 2) a
dictionary that maps keys (typically the file suffix, but see below for more discussion) to other
Scanners that should be called.
If the argument is actually a Python function, the function must take three or four arguments:
def scanner_function(node, env, path):
def scanner_function(node, env, path, arg=None):
The node argument is the internal SCons node representing the file. Use str(node) to fetch the
name of the file, and node.get_contents() to fetch contents of the file. Note that the file is
not guaranteed to exist before the scanner is called, so the scanner function should check that if
there's any chance that the scanned file might not exist (for example, if it's built from other
files).
The env argument is the construction environment for the scan. Fetch values from it using the
env.Dictionary() method.
The path argument is a tuple (or list) of directories that can be searched for files. This will
usually be the tuple returned by the path_function argument (see below).
The arg argument is the argument supplied when the scanner was created, if any.
name The name of the Scanner. This is mainly used to identify the Scanner internally.
argument
An optional argument that, if specified, will be passed to the scanner function (described above)
and the path function (specified below).
skeys An optional list that can be used to determine which scanner should be used for a given Node. In
the usual case of scanning for file names, this argument will be a list of suffixes for the
different file types that this Scanner knows how to scan. If the argument is a string, then it
will be expanded into a list by the current environment.
path_function
A Python function that takes four or five arguments: a construction environment, a Node for the
directory containing the SConscript file in which the first target was defined, a list of target
nodes, a list of source nodes, and an optional argument supplied when the scanner was created.
The path_function returns a tuple of directories that can be searched for files to be returned by
this Scanner object. (Note that the FindPathDirs() function can be used to return a ready-made
path_function for a given construction variable name, instead of having to write your own function
from scratch.)
node_class
The class of Node that should be returned by this Scanner object. Any strings or other objects
returned by the scanner function that are not of this class will be run through the node_factory
function.
node_factory
A Python function that will take a string or other object and turn it into the appropriate class
of Node to be returned by this Scanner object.
scan_check
An optional Python function that takes two arguments, a Node (file) and a construction
environment, and returns whether the Node should, in fact, be scanned for dependencies. This
check can be used to eliminate unnecessary calls to the scanner function when, for example, the
underlying file represented by a Node does not yet exist.
recursive
An optional flag that specifies whether this scanner should be re-invoked on the dependency files
returned by the scanner. When this flag is not set, the Node subsystem will only invoke the
scanner on the file being scanned, and not (for example) also on the files specified by the
#include lines in the file being scanned. recursive may be a callable function, in which case it
will be called with a list of Nodes found and should return a list of Nodes that should be scanned
recursively; this can be used to select a specific subset of Nodes for additional scanning.
Note that scons has a global SourceFileScanner object that is used by the Object(), SharedObject(), and
StaticObject() builders to decide which scanner should be used for different file extensions. You can
using the SourceFileScanner.add_scanner() method to add your own Scanner object to the scons
infrastructure that builds target programs or libraries from a list of source files of different types:
def xyz_scan(node, env, path):
contents = node.get_text_contents()
# Scan the contents and return the included files.
XYZScanner = Scanner(xyz_scan)
SourceFileScanner.add_scanner('.xyz', XYZScanner)
env.Program('my_prog', ['file1.c', 'file2.f', 'file3.xyz'])
SYSTEM-SPECIFIC BEHAVIOR
SCons and its configuration files are very portable, due largely to its implementation in Python. There
are, however, a few portability issues waiting to trap the unwary.
.C file suffix
SCons handles the upper-case .C file suffix differently, depending on the capabilities of the underlying
system. On a case-sensitive system such as Linux or UNIX, SCons treats a file with a .C suffix as a C++
source file. On a case-insensitive system such as Windows, SCons treats a file with a .C suffix as a C
source file.
.F file suffix
SCons handles the upper-case .F file suffix differently, depending on the capabilities of the underlying
system. On a case-sensitive system such as Linux or UNIX, SCons treats a file with a .F suffix as a
Fortran source file that is to be first run through the standard C preprocessor. On a case-insensitive
system such as Windows, SCons treats a file with a .F suffix as a Fortran source file that should not be
run through the C preprocessor.
Windows: Cygwin Tools and Cygwin Python vs. Windows Pythons
Cygwin supplies a set of tools and utilities that let users work on a Windows system using a more POSIX-
like environment. The Cygwin tools, including Cygwin Python, do this, in part, by sharing an ability to
interpret UNIX-like path names. For example, the Cygwin tools will internally translate a Cygwin path
name like /cygdrive/c/mydir to an equivalent Windows pathname of C:/mydir (equivalent to C:\mydir).
Versions of Python that are built for native Windows execution, such as the python.org and ActiveState
versions, do not have the Cygwin path name semantics. This means that using a native Windows version of
Python to build compiled programs using Cygwin tools (such as gcc, bison, and flex) may yield
unpredictable results. "Mixing and matching" in this way can be made to work, but it requires careful
attention to the use of path names in your SConscript files.
In practice, users can sidestep the issue by adopting the following rules: When using gcc, use the
Cygwin-supplied Python interpreter to run SCons; when using Microsoft Visual C/C++ (or some other Windows
compiler) use the python.org or ActiveState version of Python to run SCons.
Windows: scons.bat file
On Windows systems, SCons is executed via a wrapper scons.bat file. This has (at least) two
ramifications:
First, Windows command-line users that want to use variable assignment on the command line may have to
put double quotes around the assignments:
scons "FOO=BAR" "BAZ=BLEH"
Second, the Cygwin shell does not recognize this file as being the same as an scons command issued at the
command-line prompt. You can work around this either by executing scons.bat from the Cygwin command
line, or by creating a wrapper shell script named scons .
MinGW
The MinGW bin directory must be in your PATH environment variable or the PATH variable under the ENV
construction variable for SCons to detect and use the MinGW tools. When running under the native Windows
Python interpreter, SCons will prefer the MinGW tools over the Cygwin tools, if they are both installed,
regardless of the order of the bin directories in the PATH variable. If you have both MSVC and MinGW
installed and you want to use MinGW instead of MSVC, then you must explicitly tell SCons to use MinGW by
passing
tools=['mingw']
to the Environment() function, because SCons will prefer the MSVC tools over the MinGW tools.
EXAMPLES
To help you get started using SCons, this section contains a brief overview of some common tasks.
Basic Compilation From a Single Source File
env = Environment()
env.Program(target = 'foo', source = 'foo.c')
Note: Build the file by specifying the target as an argument ("scons foo" or "scons foo.exe"). or by
specifying a dot ("scons .").
Basic Compilation From Multiple Source Files
env = Environment()
env.Program(target = 'foo', source = Split('f1.c f2.c f3.c'))
Setting a Compilation Flag
env = Environment(CCFLAGS = '-g')
env.Program(target = 'foo', source = 'foo.c')
Search The Local Directory For .h Files
Note: You do not need to set CCFLAGS to specify -I options by hand. SCons will construct the right -I
options from CPPPATH.
env = Environment(CPPPATH = ['.'])
env.Program(target = 'foo', source = 'foo.c')
Search Multiple Directories For .h Files
env = Environment(CPPPATH = ['include1', 'include2'])
env.Program(target = 'foo', source = 'foo.c')
Building a Static Library
env = Environment()
env.StaticLibrary(target = 'foo', source = Split('l1.c l2.c'))
env.StaticLibrary(target = 'bar', source = ['l3.c', 'l4.c'])
Building a Shared Library
env = Environment()
env.SharedLibrary(target = 'foo', source = ['l5.c', 'l6.c'])
env.SharedLibrary(target = 'bar', source = Split('l7.c l8.c'))
Linking a Local Library Into a Program
env = Environment(LIBS = 'mylib', LIBPATH = ['.'])
env.Library(target = 'mylib', source = Split('l1.c l2.c'))
env.Program(target = 'prog', source = ['p1.c', 'p2.c'])
Defining Your Own Builder Object
Notice that when you invoke the Builder, you can leave off the target file suffix, and SCons will add it
automatically.
bld = Builder(action = 'pdftex < $SOURCES > $TARGET'
suffix = '.pdf',
src_suffix = '.tex')
env = Environment(BUILDERS = {'PDFBuilder' : bld})
env.PDFBuilder(target = 'foo.pdf', source = 'foo.tex')
# The following creates "bar.pdf" from "bar.tex"
env.PDFBuilder(target = 'bar', source = 'bar')
Note also that the above initialization overwrites the default Builder objects, so the Environment
created above can not be used call Builders like env.Program(), env.Object(), env.StaticLibrary(), etc.
Adding Your Own Builder Object to an Environment
bld = Builder(action = 'pdftex < $SOURCES > $TARGET'
suffix = '.pdf',
src_suffix = '.tex')
env = Environment()
env.Append(BUILDERS = {'PDFBuilder' : bld})
env.PDFBuilder(target = 'foo.pdf', source = 'foo.tex')
env.Program(target = 'bar', source = 'bar.c')
You also can use other Pythonic techniques to add to the BUILDERS construction variable, such as:
env = Environment()
env['BUILDERS]['PDFBuilder'] = bld
Defining Your Own Scanner Object
The following example shows an extremely simple scanner (the kfile_scan() function) that doesn't use a
search path at all and simply returns the file names present on any include lines in the scanned file.
This would implicitly assume that all included files live in the top-level directory:
import re
include_re = re.compile(r'^include\s+(\S+)$', re.M)
def kfile_scan(node, env, path, arg):
contents = node.get_text_contents()
includes = include_re.findall(contents)
return env.File(includes)
kscan = Scanner(name = 'kfile',
function = kfile_scan,
argument = None,
skeys = ['.k'])
scanners = Environment().Dictionary('SCANNERS')
env = Environment(SCANNERS = scanners + [kscan])
env.Command('foo', 'foo.k', 'kprocess < $SOURCES > $TARGET')
bar_in = File('bar.in')
env.Command('bar', bar_in, 'kprocess $SOURCES > $TARGET')
bar_in.target_scanner = kscan
It is important to note that you have to return a list of File nodes from the scan function, simple
strings for the file names won't do. As in the examples we are showing here, you can use the File()
function of your current Environment in order to create nodes on the fly from a sequence of file names
with relative paths.
Here is a similar but more complete example that searches a path of directories (specified as the MYPATH
construction variable) for files that actually exist:
import re
import os
include_re = re.compile(r'^include\s+(\S+)$', re.M)
def my_scan(node, env, path, arg):
contents = node.get_text_contents()
includes = include_re.findall(contents)
if includes == []:
return []
results = []
for inc in includes:
for dir in path:
file = str(dir) + os.sep + inc
if os.path.exists(file):
results.append(file)
break
return env.File(results)
scanner = Scanner(name = 'myscanner',
function = my_scan,
argument = None,
skeys = ['.x'],
path_function = FindPathDirs('MYPATH')
)
scanners = Environment().Dictionary('SCANNERS')
env = Environment(SCANNERS = scanners + [scanner],
MYPATH = ['incs'])
env.Command('foo', 'foo.x', 'xprocess < $SOURCES > $TARGET')
The FindPathDirs() function used in the previous example returns a function (actually a callable Python
object) that will return a list of directories specified in the $MYPATH construction variable. It lets
SCons detect the file incs/foo.inc , even if foo.x contains the line include foo.inc only. If you need
to customize how the search path is derived, you would provide your own path_function argument when
creating the Scanner object, as follows:
# MYPATH is a list of directories to search for files in
def pf(env, dir, target, source, arg):
top_dir = Dir('#').abspath
results = []
if 'MYPATH' in env:
for p in env['MYPATH']:
results.append(top_dir + os.sep + p)
return results
scanner = Scanner(name = 'myscanner',
function = my_scan,
argument = None,
skeys = ['.x'],
path_function = pf
)
Creating a Hierarchical Build
Notice that the file names specified in a subdirectory's SConscript file are relative to that
subdirectory.
SConstruct:
env = Environment()
env.Program(target = 'foo', source = 'foo.c')
SConscript('sub/SConscript')
sub/SConscript:
env = Environment()
# Builds sub/foo from sub/foo.c
env.Program(target = 'foo', source = 'foo.c')
SConscript('dir/SConscript')
sub/dir/SConscript:
env = Environment()
# Builds sub/dir/foo from sub/dir/foo.c
env.Program(target = 'foo', source = 'foo.c')
Sharing Variables Between SConscript Files
You must explicitly Export() and Import() variables that you want to share between SConscript files.
SConstruct:
env = Environment()
env.Program(target = 'foo', source = 'foo.c')
Export("env")
SConscript('subdirectory/SConscript')
subdirectory/SConscript:
Import("env")
env.Program(target = 'foo', source = 'foo.c')
Building Multiple Variants From the Same Source
Use the variant_dir keyword argument to the SConscript function to establish one or more separate variant
build directory trees for a given source directory:
SConstruct:
cppdefines = ['FOO']
Export("cppdefines")
SConscript('src/SConscript', variant_dir='foo')
cppdefines = ['BAR']
Export("cppdefines")
SConscript('src/SConscript', variant_dir='bar')
src/SConscript:
Import("cppdefines")
env = Environment(CPPDEFINES = cppdefines)
env.Program(target = 'src', source = 'src.c')
Note the use of the Export() method to set the "cppdefines" variable to a different value each time we
call the SConscript function.
Hierarchical Build of Two Libraries Linked With a Program
SConstruct:
env = Environment(LIBPATH = ['#libA', '#libB'])
Export('env')
SConscript('libA/SConscript')
SConscript('libB/SConscript')
SConscript('Main/SConscript')
libA/SConscript:
Import('env')
env.Library('a', Split('a1.c a2.c a3.c'))
libB/SConscript:
Import('env')
env.Library('b', Split('b1.c b2.c b3.c'))
Main/SConscript:
Import('env')
e = env.Copy(LIBS = ['a', 'b'])
e.Program('foo', Split('m1.c m2.c m3.c'))
The '#' in the LIBPATH directories specify that they're relative to the top-level directory, so they
don't turn into "Main/libA" when they're used in Main/SConscript.
Specifying only 'a' and 'b' for the library names allows SCons to append the appropriate library prefix
and suffix for the current platform (for example, 'liba.a' on POSIX systems, 'a.lib' on Windows).
Customizing construction variables from the command line.
The following would allow the C compiler to be specified on the command line or in the file custom.py.
vars = Variables('custom.py')
vars.Add('CC', 'The C compiler.')
env = Environment(variables=vars)
Help(vars.GenerateHelpText(env))
The user could specify the C compiler on the command line:
scons "CC=my_cc"
or in the custom.py file:
CC = 'my_cc'
or get documentation on the options:
$ scons -h
CC: The C compiler.
default: None
actual: cc
Using Microsoft Visual C++ precompiled headers
Since windows.h includes everything and the kitchen sink, it can take quite some time to compile it over
and over again for a bunch of object files, so Microsoft provides a mechanism to compile a set of headers
once and then include the previously compiled headers in any object file. This technology is called
precompiled headers. The general recipe is to create a file named "StdAfx.cpp" that includes a single
header named "StdAfx.h", and then include every header you want to precompile in "StdAfx.h", and finally
include "StdAfx.h" as the first header in all the source files you are compiling to object files. For
example:
StdAfx.h:
#include <windows.h>
#include <my_big_header.h>
StdAfx.cpp:
#include <StdAfx.h>
Foo.cpp:
#include <StdAfx.h>
/* do some stuff */
Bar.cpp:
#include <StdAfx.h>
/* do some other stuff */
SConstruct:
env=Environment()
env['PCHSTOP'] = 'StdAfx.h'
env['PCH'] = env.PCH('StdAfx.cpp')[0]
env.Program('MyApp', ['Foo.cpp', 'Bar.cpp'])
For more information see the document for the PCH builder, and the PCH and PCHSTOP construction
variables. To learn about the details of precompiled headers consult the MSDN documention for /Yc, /Yu,
and /Yp.
Using Microsoft Visual C++ external debugging information
Since including debugging information in programs and shared libraries can cause their size to increase
significantly, Microsoft provides a mechanism for including the debugging information in an external file
called a PDB file. SCons supports PDB files through the PDB construction variable.
SConstruct:
env=Environment()
env['PDB'] = 'MyApp.pdb'
env.Program('MyApp', ['Foo.cpp', 'Bar.cpp'])
For more information see the document for the PDB construction variable.
ENVIRONMENT
SCONS_LIB_DIR
Specifies the directory that contains the SCons Python module directory (e.g. /home/aroach/scons-
src-0.01/src/engine).
SCONSFLAGS
A string of options that will be used by scons in addition to those passed on the command line.
SEE ALSO
scons User Manual, scons Design Document, scons source code.
AUTHORS
Steven Knight <knight@baldmt.com>
Anthony Roach <aroach@electriceyeball.com>
March 2013 SCONS(1)