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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | SEE ALSO | BUGS | AUTHOR | COPYRIGHT | COLOPHON |
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MAKE(1) User Commands MAKE(1)
make - GNU make utility to maintain groups of programs
make [OPTION]... [TARGET]...
The make utility will 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 very 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
provides 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 description 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 makefile.
make executes commands in the makefile to update one or more
targets, where target 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 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 any or all of the following
names, comma- or space-separated. Only the first character
is significant: the rest may be omitted: all for all
debugging output (same as using -d), basic for basic
debugging, verbose for more verbose basic debugging, implicit
for showing implicit rule search operations, jobs for details
on invocation of commands, makefile for debugging while
remaking makefiles, print shows all recipes that are run even
if they are silent, and why shows the reason make decided to
rebuild each target. Use none to disable all previous
debugging flags.
-e, --environment-overrides
Give variables taken from the environment precedence over
variables from makefiles.
-E string, --eval string
Interpret string using the eval function, before parsing any
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.
--jobserver-style=style
The style of jobserver to use. The style may be one of fifo,
pipe, or sem (Windows only).
-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 (except in certain circumstances).
-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.
-O[type], --output-sync[=type]
When running multiple jobs in parallel with -j, ensure the
output of each job is collected together rather than
interspersed with output from other jobs. If type is not
specified or is target the output from the entire recipe for
each target is grouped together. If type is line the output
from each command line within a recipe is grouped together.
If type is recurse output from an entire recursive make is
grouped together. If type is none output synchronization is
disabled.
-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.
--no-silent
Cancel the effect of the -s option.
-S, --no-keep-going, --stop
Cancel the effect of the -k option.
-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.
--trace
Information about the disposition of each target is printed
(why the target is being rebuilt and what commands are run to
rebuild it).
-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.
--shuffle[=MODE]
Enable shuffling of goal and prerequisite ordering. MODE is
one of none to disable shuffle mode, random to shuffle
prerequisites in random order, reverse to consider
prerequisites in reverse order, or an integer <seed> which
enables random mode with a specific seed value. If MODE is
omitted the default is random.
-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.
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 full documentation for make is maintained as a Texinfo manual.
If the info and make programs are properly installed at your site,
the command
info make
should give you access to the complete manual.
See the chapter ``Problems and Bugs'' in The GNU Make Manual.
This manual page contributed by Dennis Morse of Stanford
University. Further updates contributed by Mike Frysinger. It
has been reworked by Roland McGrath. Maintained by Paul Smith.
Copyright © 1992-1993, 1996-2022 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 3 of the License,
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 this program. If not, see
https://www.gnu.org/licenses/ .
This page is part of the make (GNU make) project. Information
about the project can be found at
⟨http://www.gnu.org/software/make/⟩. If you have a bug report for
this manual page, see ⟨http://www.gnu.org/software/make/⟩. This
page was obtained from the tarball make-4.4.tar.gz fetched from
⟨http://ftp.gnu.org/gnu/make/⟩ on 2025-08-11. If you discover any
rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page,
or you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a
mail to [email protected]
GNU 31 May 2022 MAKE(1)
Pages that refer to this page: dh_assistant(1), dpkg-buildflags(1), dpkg-buildpackage(1), pkgdata(1), time(1), adjtime(3), pmdatrace(3), debhelper-compat-upgrade-checklist(7), sched(7), suffixes(7)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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