Provided by: make_3.81-8.1ubuntu1_amd64 bug

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

       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.