{ "mode": "man", "parameter": "MAKE", "section": "1", "url": "https://www.chedong.com/phpMan.php/man/MAKE/1/json", "generated": "2026-06-03T11:12:02Z", "synopsis": "make [OPTION]... [TARGET]...", "sections": { "NAME": { "content": "make - GNU make utility to maintain groups of programs\n", "subsections": [] }, "SYNOPSIS": { "content": "make [OPTION]... [TARGET]...\n", "subsections": [] }, "DESCRIPTION": { "content": "The make utility will determine automatically which pieces of a large program need to be re‐\ncompiled, and issue the commands to recompile them. The manual describes the GNU implementa‐\ntion of make, which was written by Richard Stallman and Roland McGrath, and is currently\nmaintained by Paul Smith. Our examples show C programs, since they are very common, but you\ncan use make with any programming language whose compiler can be run with a shell command.\nIn fact, make is not limited to programs. You can use it to describe any task where some\nfiles must be updated automatically from others whenever the others change.\n\nTo prepare to use make, you must write a file called the makefile that describes the rela‐\ntionships among files in your program, and the states the commands for updating each file.\nIn a program, typically the executable file is updated from object files, which are in turn\nmade by compiling source files.\n\nOnce a suitable makefile exists, each time you change some source files, this simple shell\ncommand:\n\nmake\n\nsuffices to perform all necessary recompilations. The make program uses the makefile de‐\nscription and the last-modification times of the files to decide which of the files need to\nbe updated. For each of those files, it issues the commands recorded in the makefile.\n\nmake executes commands in the makefile to update one or more target names, where name is typ‐\nically a program. If no -f option is present, make will look for the makefiles GNUmakefile,\nmakefile, and Makefile, in that order.\n\nNormally you should call your makefile either makefile or Makefile. (We recommend Makefile\nbecause it appears prominently near the beginning of a directory listing, right near other\nimportant files such as README.) The first name checked, GNUmakefile, is not recommended for\nmost makefiles. You should use this name if you have a makefile that is specific to GNU\nmake, and will not be understood by other versions of make. If makefile is '-', the standard\ninput is read.\n\nmake updates a target if it depends on prerequisite files that have been modified since the\ntarget was last modified, or if the target does not exist.\n", "subsections": [] }, "OPTIONS": { "content": "", "subsections": [ { "name": "-b -m", "content": "These options are ignored for compatibility with other versions of make.\n", "flag": "-m" }, { "name": "-B --always-make", "content": "Unconditionally make all targets.\n", "flag": "-B", "long": "--always-make" }, { "name": "-C --directory", "content": "Change to directory dir before reading the makefiles or doing anything else. If multi‐\nple -C options are specified, each is interpreted relative to the previous one: -C / -C\netc is equivalent to -C /etc. This is typically used with recursive invocations of\nmake.\n", "flag": "-C", "long": "--directory" }, { "name": "-d", "content": "says which files are being considered for remaking, which file-times are being compared\nand with what results, which files actually need to be remade, which implicit rules are\nconsidered and which are applied---everything interesting about how make decides what to\ndo.\n\n--debug[=FLAGS]\nPrint debugging information in addition to normal processing. If the FLAGS are omitted,\nthen the behavior is the same as if -d was specified. FLAGS may be a for all debugging\noutput (same as using -d), b for basic debugging, v for more verbose basic debugging, i\nfor showing implicit rules, j for details on invocation of commands, and m for debugging\nwhile remaking makefiles. Use n to disable all previous debugging flags.\n", "flag": "-d" }, { "name": "-e --environment-overrides", "content": "Give variables taken from the environment precedence over variables from makefiles.\n", "flag": "-e", "long": "--environment-overrides" }, { "name": "-f --file --makefile", "content": "Use file as a makefile.\n", "flag": "-f", "long": "--makefile" }, { "name": "-i --ignore-errors", "content": "Ignore all errors in commands executed to remake files.\n", "flag": "-i", "long": "--ignore-errors" }, { "name": "-I --include-dir", "content": "Specifies a directory dir to search for included makefiles. If several -I options are\nused to specify several directories, the directories are searched in the order speci‐\nfied. Unlike the arguments to other flags of make, directories given with -I flags may\ncome directly after the flag: -Idir is allowed, as well as -I dir. This syntax is al‐\nlowed for compatibility with the C preprocessor's -I flag.\n", "flag": "-I", "long": "--include-dir" }, { "name": "-j --jobs", "content": "Specifies the number of jobs (commands) to run simultaneously. If there is more than\none -j option, the last one is effective. If the -j option is given without an argu‐\nment, make will not limit the number of jobs that can run simultaneously. When make in‐\nvokes a sub-make, all instances of make will coordinate to run the specified number of\njobs at a time; see the section PARALLEL MAKE AND THE JOBSERVER for details.\n\n--jobserver-fds [R,W]\nInternal option make uses to pass the jobserver pipe read and write file descriptor num‐\nbers to sub-makes; see the section PARALLEL MAKE AND THE JOBSERVER for details\n", "flag": "-j", "long": "--jobs" }, { "name": "-k --keep-going", "content": "Continue as much as possible after an error. While the target that failed, and those\nthat depend on it, cannot be remade, the other dependencies of these targets can be pro‐\ncessed all the same.\n", "flag": "-k", "long": "--keep-going" }, { "name": "-l --load-average", "content": "Specifies that no new jobs (commands) should be started if there are others jobs running\nand the load average is at least load (a floating-point number). With no argument, re‐\nmoves a previous load limit.\n", "flag": "-l", "long": "--load-average" }, { "name": "-L --check-symlink-times", "content": "Use the latest mtime between symlinks and target.\n", "flag": "-L", "long": "--check-symlink-times" }, { "name": "-n --just-print --dry-run --recon", "content": "Print the commands that would be executed, but do not execute them (except in certain\ncircumstances).\n", "flag": "-n", "long": "--recon" }, { "name": "-o --old-file --assume-old", "content": "Do not remake the file file even if it is older than its dependencies, and do not remake\nanything on account of changes in file. Essentially the file is treated as very old and\nits rules are ignored.\n", "flag": "-o", "long": "--assume-old" }, { "name": "-O --output-sync", "content": "When running multiple jobs in parallel with -j, ensure the output of each job is col‐\nlected together rather than interspersed with output from other jobs. If type is not\nspecified or is target the output from the entire recipe for each target is grouped to‐\ngether. If type is line the output from each command line within a recipe is grouped\ntogether. If type is recurse output from an entire recursive make is grouped together.\nIf type is none output synchronization is disabled.\n", "flag": "-O", "long": "--output-sync" }, { "name": "-p --print-data-base", "content": "Print the data base (rules and variable values) that results from reading the makefiles;\nthen execute as usual or as otherwise specified. This also prints the version informa‐\ntion given by the -v switch (see below). To print the data base without trying to re‐\nmake any files, use make -p -f/dev/null.\n", "flag": "-p", "long": "--print-data-base" }, { "name": "-q --question", "content": "``Question mode''. Do not run any commands, or print anything; just return an exit sta‐\ntus that is zero if the specified targets are already up to date, nonzero otherwise.\n", "flag": "-q", "long": "--question" }, { "name": "-r --no-builtin-rules", "content": "Eliminate use of the built-in implicit rules. Also clear out the default list of suf‐\nfixes for suffix rules.\n", "flag": "-r", "long": "--no-builtin-rules" }, { "name": "-R --no-builtin-variables", "content": "Don't define any built-in variables.\n", "flag": "-R", "long": "--no-builtin-variables" }, { "name": "-s --silent --quiet", "content": "Silent operation; do not print the commands as they are executed.\n", "flag": "-s", "long": "--quiet" }, { "name": "-S --no-keep-going --stop", "content": "Cancel the effect of the -k option. This is never necessary except in a recursive make\nwhere -k might be inherited from the top-level make via MAKEFLAGS or if you set -k in\nMAKEFLAGS in your environment.\n", "flag": "-S", "long": "--stop" }, { "name": "-t --touch", "content": "Touch files (mark them up to date without really changing them) instead of running their\ncommands. This is used to pretend that the commands were done, in order to fool future\ninvocations of make.\n", "flag": "-t", "long": "--touch" }, { "name": "--trace", "content": "Information about the disposition of each target is printed (why the target is being re‐\nbuilt and what commands are run to rebuild it).\n", "long": "--trace" }, { "name": "-v --version", "content": "Print the version of the make program plus a copyright, a list of authors and a notice\nthat there is no warranty.\n", "flag": "-v", "long": "--version" }, { "name": "-w --print-directory", "content": "Print a message containing the working directory before and after other processing.\nThis may be useful for tracking down errors from complicated nests of recursive make\ncommands.\n", "flag": "-w", "long": "--print-directory" }, { "name": "--no-print-directory", "content": "Turn off -w, even if it was turned on implicitly.\n", "long": "--no-print-directory" }, { "name": "-W --what-if --new-file --assume-new", "content": "Pretend that the target file has just been modified. When used with the -n flag, this\nshows you what would happen if you were to modify that file. Without -n, it is almost\nthe same as running a touch command on the given file before running make, except that\nthe modification time is changed only in the imagination of make.\n", "flag": "-W", "long": "--assume-new" }, { "name": "--warn-undefined-variables", "content": "Warn when an undefined variable is referenced.\n", "long": "--warn-undefined-variables" } ] }, "EXIT STATUS": { "content": "GNU make exits with a status of zero if all makefiles were successfully parsed and no targets\nthat were built failed. A status of one will be returned if the -q flag was used and make\ndetermines that a target needs to be rebuilt. A status of two will be returned if any errors\nwere encountered.\n", "subsections": [] }, "SEE ALSO": { "content": "The full documentation for make is maintained as a Texinfo manual. If the info and make pro‐\ngrams are properly installed at your site, the command\n\ninfo make\n\nshould give you access to the complete manual. Additionally, the manual is also available on‐\nline at https://www.gnu.org/software/make/manual/htmlnode/index.html\n", "subsections": [] }, "PARALLEL MAKE AND THE JOBSERVER": { "content": "Using the -j option, the user can instruct make to execute tasks in parallel. By specifying a\nnumeric argument to -j the user may specify an upper limit of the number of parallel tasks to\nbe run.\n\nWhen the build environment is such that a top level make invokes sub-makes (for instance, a\nstyle in which each sub-directory contains its own Makefile ), no individual instance of make\nknows how many tasks are running in parallel, so keeping the number of tasks under the upper\nlimit would be impossible without communication between all the make instances running. While\nsolutions like having the top level make serve as a central controller are feasible, or using\nother synchronization mechanisms like shared memory or sockets can be created, the current\nimplementation uses a simple shared pipe.\n\nThis pipe is created by the top-level make process, and passed on to all the sub-makes. The\ntop level makeprocesswrites N-1 one-byte tokens into the pipe (The top level make is assumed\nto reserve one token for itself). Whenever any of the make processes (including the top-level\nmake ) needs to run a new task, it reads a byte from the shared pipe. If there are no tokens\nleft, it must wait for a token to be written back to the pipe. Once the task is completed,\nthe make process writes a token back to the pipe (and thus, if the tokens had been exhausted,\nunblocking the first make process that was waiting to read a token). Since only N-1 tokens\nwere written into the pipe, no more than N tasks can be running at any given time.\n\nIf the job to be run is not a sub-make then make will close the jobserver pipe file descrip‐\ntors before invoking the commands, so that the command can not interfere with the jobserver,\nand the command does not find any unusual file descriptors.\n", "subsections": [] }, "BUGS": { "content": "See the chapter ``Problems and Bugs'' in The GNU Make Manual.\n", "subsections": [] }, "AUTHOR": { "content": "This manual page contributed by Dennis Morse of Stanford University. Further updates con‐\ntributed by Mike Frysinger. It has been reworked by Roland McGrath. Maintained by Paul\nSmith.\n", "subsections": [] }, "COPYRIGHT": { "content": "Copyright © 1992-1993, 1996-2016 Free Software Foundation, Inc. This file is part of GNU\nmake.\n\nGNU Make is free software; you can redistribute it and/or modify it under the terms of the\nGNU General Public License as published by the Free Software Foundation; either version 3 of\nthe License, or (at your option) any later version.\n\nGNU Make is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without\neven the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\nGNU General Public License for more details.\n\nYou should have received a copy of the GNU General Public License along with this program.\nIf not, see http://www.gnu.org/licenses/.\n\n\n\nGNU 28 February 2016 MAKE(1)", "subsections": [] } }, "summary": "make - GNU make utility to maintain groups of programs", "flags": [ { "flag": "-m", "long": null, "arg": null, "description": "These options are ignored for compatibility with other versions of make." }, { "flag": "-B", "long": "--always-make", "arg": null, "description": "Unconditionally make all targets." }, { "flag": "-C", "long": "--directory", "arg": null, "description": "Change to directory dir before reading the makefiles or doing anything else. If multi‐ ple -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." }, { "flag": "-d", "long": null, "arg": null, "description": "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. Use n to disable all previous debugging flags." }, { "flag": "-e", "long": "--environment-overrides", "arg": null, "description": "Give variables taken from the environment precedence over variables from makefiles." }, { "flag": "-f", "long": "--makefile", "arg": null, "description": "Use file as a makefile." }, { "flag": "-i", "long": "--ignore-errors", "arg": null, "description": "Ignore all errors in commands executed to remake files." }, { "flag": "-I", "long": "--include-dir", "arg": null, "description": "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 speci‐ fied. 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 al‐ lowed for compatibility with the C preprocessor's -I flag." }, { "flag": "-j", "long": "--jobs", "arg": null, "description": "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 argu‐ ment, make will not limit the number of jobs that can run simultaneously. When make in‐ vokes a sub-make, all instances of make will coordinate to run the specified number of jobs at a time; see the section PARALLEL MAKE AND THE JOBSERVER for details. --jobserver-fds [R,W] Internal option make uses to pass the jobserver pipe read and write file descriptor num‐ bers to sub-makes; see the section PARALLEL MAKE AND THE JOBSERVER for details" }, { "flag": "-k", "long": "--keep-going", "arg": null, "description": "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 pro‐ cessed all the same." }, { "flag": "-l", "long": "--load-average", "arg": null, "description": "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, re‐ moves a previous load limit." }, { "flag": "-L", "long": "--check-symlink-times", "arg": null, "description": "Use the latest mtime between symlinks and target." }, { "flag": "-n", "long": "--recon", "arg": null, "description": "Print the commands that would be executed, but do not execute them (except in certain circumstances)." }, { "flag": "-o", "long": "--assume-old", "arg": null, "description": "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." }, { "flag": "-O", "long": "--output-sync", "arg": null, "description": "When running multiple jobs in parallel with -j, ensure the output of each job is col‐ lected 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 to‐ gether. 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." }, { "flag": "-p", "long": "--print-data-base", "arg": null, "description": "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 informa‐ tion given by the -v switch (see below). To print the data base without trying to re‐ make any files, use make -p -f/dev/null." }, { "flag": "-q", "long": "--question", "arg": null, "description": "``Question mode''. Do not run any commands, or print anything; just return an exit sta‐ tus that is zero if the specified targets are already up to date, nonzero otherwise." }, { "flag": "-r", "long": "--no-builtin-rules", "arg": null, "description": "Eliminate use of the built-in implicit rules. Also clear out the default list of suf‐ fixes for suffix rules." }, { "flag": "-R", "long": "--no-builtin-variables", "arg": null, "description": "Don't define any built-in variables." }, { "flag": "-s", "long": "--quiet", "arg": null, "description": "Silent operation; do not print the commands as they are executed." }, { "flag": "-S", "long": "--stop", "arg": null, "description": "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." }, { "flag": "-t", "long": "--touch", "arg": null, "description": "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." }, { "flag": "", "long": "--trace", "arg": null, "description": "Information about the disposition of each target is printed (why the target is being re‐ built and what commands are run to rebuild it)." }, { "flag": "-v", "long": "--version", "arg": null, "description": "Print the version of the make program plus a copyright, a list of authors and a notice that there is no warranty." }, { "flag": "-w", "long": "--print-directory", "arg": null, "description": "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." }, { "flag": "", "long": "--no-print-directory", "arg": null, "description": "Turn off -w, even if it was turned on implicitly." }, { "flag": "-W", "long": "--assume-new", "arg": null, "description": "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." }, { "flag": "", "long": "--warn-undefined-variables", "arg": null, "description": "Warn when an undefined variable is referenced." } ], "examples": [], "see_also": [] }