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       make - GNU make utility to maintain groups of programs


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


       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
       which is made from the Texinfo source file make.texi.


       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:


       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.


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

       -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.

            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

       -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

       -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

       -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

       -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.

            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 when an undefined variable is referenced.


       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.


       The GNU Make Manual


       See the chapter ‘Problems and Bugs’ in The GNU Make Manual.


       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.