trusty (1) make.1.gz

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NAME

       make - GNU make utility to maintain groups of programs

SYNOPSIS

       make [ -f makefile ] [ options ] ... [ targets ] ...

WARNING

       This  man  page is an extract of the documentation of GNU make.  It is updated only occasionally, because
       the GNU project does not use nroff.   For  complete,  current  documentation,  refer  to  the  Info  file
       make.info which is made from the Texinfo source file make.texi.

DESCRIPTION

       The  purpose of the make utility is to determine automatically which pieces of a large program need to be
       recompiled, and issue the commands to recompile them.  The manual describes  the  GNU  implementation  of
       make,  which  was  written  by  Richard  Stallman and Roland McGrath, and is currently maintained by Paul
       Smith.  Our examples show C programs, since they  are  most  common,  but  you  can  use  make  with  any
       programming  language  whose  compiler  can be run with a shell command.  In fact, make is not limited to
       programs.  You can use it to describe any task where some files must be updated automatically from others
       whenever the others change.

       To  prepare to use make, you must write a file called the makefile that describes the relationships among
       files in your program, and the states the commands for updating each file.  In a program,  typically  the
       executable file is updated from object files, which are in turn made by compiling source files.

       Once a suitable makefile exists, each time you change some source files, this simple shell command:

              make

       suffices  to  perform all necessary recompilations.  The make program uses the makefile data base and the
       last-modification times of the files to decide which of the files need to be updated.  For each of  those
       files, it issues the commands recorded in the data base.

       make  executes  commands  in  the  makefile to update one or more target names, where name is typically a
       program.  If no -f option is present, make  will  look  for  the  makefiles  GNUmakefile,  makefile,  and
       Makefile, in that order.

       Normally  you  should  call your makefile either makefile or Makefile.  (We recommend Makefile because it
       appears prominently near the beginning of a directory listing, right near other important files  such  as
       README.)   The  first  name  checked, GNUmakefile, is not recommended for most makefiles.  You should use
       this name if you have a makefile that is specific to GNU make,  and  will  not  be  understood  by  other
       versions of make.  If makefile is `-', the standard input is read.

       make  updates  a  target if it depends on prerequisite files that have been modified since the target was
       last modified, or if the target does not exist.

OPTIONS

       -b, -m
            These options are ignored for compatibility with other versions of make.

       -B, --always-make
            Unconditionally make all targets.

       -C dir, --directory=dir
            Change to directory dir before reading the makefiles or doing anything else.  If multiple -C options
            are  specified,  each  is  interpreted relative to the previous one: -C / -C etc is equivalent to -C
            /etc.  This is typically used with recursive invocations of make.

       -d   Print debugging information in addition to normal processing.  The debugging information says  which
            files  are being considered for remaking, which file-times are being compared and with what results,
            which files actually need  to  be  remade,  which  implicit  rules  are  considered  and  which  are
            applied---everything interesting about how make decides what to do.

       --debug[=FLAGS]
            Print  debugging  information  in addition to normal processing.  If the FLAGS are omitted, then the
            behavior is the same as if -d was specified.  FLAGS may be a for all debugging output (same as using
            -d),  b for basic debugging, v for more verbose basic debugging, i for showing implicit rules, j for
            details on invocation of commands, and m for debugging while remaking makefiles.

       -e, --environment-overrides
            Give variables taken from the environment precedence over variables from makefiles.

       -f file, --file=file, --makefile=FILE
            Use file as a makefile.

       -i, --ignore-errors
            Ignore all errors in commands executed to remake files.

       -I dir, --include-dir=dir
            Specifies a directory dir to search for included makefiles.  If  several  -I  options  are  used  to
            specify  several  directories,  the  directories  are  searched  in the order specified.  Unlike the
            arguments to other flags of make, directories given with -I flags may come directly after the  flag:
            -Idir  is  allowed,  as  well  as  -I  dir.   This  syntax  is  allowed for compatibility with the C
            preprocessor's -I flag.

       -j [jobs], --jobs[=jobs]
            Specifies the number of jobs (commands) to run simultaneously.  If there is more than one -j option,
            the  last  one is effective.  If the -j option is given without an argument, make will not limit the
            number of jobs that can run simultaneously.

       -k, --keep-going
            Continue as much as possible after an error.  While the target that failed, and those that depend on
            it, cannot be remade, the other dependencies of these targets can be processed all the same.

       -l [load], --load-average[=load]
            Specifies  that  no  new  jobs (commands) should be started if there are others jobs running and the
            load average is at least load (a floating-point number).  With no argument, removes a previous  load
            limit.

       -L, --check-symlink-times
            Use the latest mtime between symlinks and target.

       -n, --just-print, --dry-run, --recon
            Print the commands that would be executed, but do not execute them.

       -o file, --old-file=file, --assume-old=file
            Do not remake the file file even if it is older than its dependencies, and do not remake anything on
            account of changes in file.  Essentially the file is treated as very old and its rules are ignored.

       -p, --print-data-base
            Print the data base (rules and variable values)  that  results  from  reading  the  makefiles;  then
            execute  as  usual or as otherwise specified.  This also prints the version information given by the
            -v switch (see below).  To print the data base without trying to  remake  any  files,  use  make  -p
            -f/dev/null.

       -q, --question
            ``Question  mode''.   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, nonzero otherwise.

       -r, --no-builtin-rules
            Eliminate use of the built-in implicit rules.  Also clear out  the  default  list  of  suffixes  for
            suffix rules.

       -R, --no-builtin-variables
            Don't define any built-in variables.

       -s, --silent, --quiet
            Silent operation; do not print the commands as they are executed.

       -S, --no-keep-going, --stop
            Cancel  the  effect  of  the -k option.  This is never necessary except in a recursive make where -k
            might be inherited from the top-level make via MAKEFLAGS or if you  set  -k  in  MAKEFLAGS  in  your
            environment.

       -t, --touch
            Touch  files  (mark them up to date without really changing them) instead of running their commands.
            This is used to pretend that the commands were done, in order to fool future invocations of make.

       -v, --version
            Print the version of the make program plus a copyright, a list of authors and a notice that there is
            no warranty.

       -w, --print-directory
            Print  a  message  containing  the working directory before and after other processing.  This may be
            useful for tracking down errors from complicated nests of recursive make commands.

       --no-print-directory
            Turn off -w, even if it was turned on implicitly.

       -W file, --what-if=file, --new-file=file, --assume-new=file
            Pretend that the target file has just been modified.  When used with the -n  flag,  this  shows  you
            what  would  happen if you were to modify that file.  Without -n, it is almost the same as running a
            touch command on the given file before running make, except that the modification  time  is  changed
            only in the imagination of make.

       --warn-undefined-variables
            Warn when an undefined variable is referenced.

EXIT STATUS

       GNU  make  exits with a status of zero if all makefiles were successfully parsed and no targets that were
       built failed.  A status of one will be returned if the -q flag was used and make determines that a target
       needs to be rebuilt.  A status of two will be returned if any errors were encountered.

SEE ALSO

       The GNU Make Manual

BUGS

       See the chapter `Problems and Bugs' in The GNU Make Manual.

AUTHOR

       This  manual  page  contributed  by  Dennis Morse of Stanford University.  It has been reworked by Roland
       McGrath.  Further updates contributed by Mike Frysinger.

       Copyright (C) 1992, 1993, 1996, 1999 Free Software Foundation, Inc.  This file is part of GNU make.

       GNU make is free software; you can redistribute it and/or modify it under the terms of  the  GNU  General
       Public  License  as  published by the Free Software Foundation; either version 2, or (at your option) any
       later version.

       GNU make is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;  without  even  the
       implied  warranty  of  MERCHANTABILITY  or  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
       License for more details.

       You should have received a copy of the GNU General Public License along  with  GNU  make;  see  the  file
       COPYING.   If  not,  write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
       02110-1301, USA.