MAKE(1L)							LOCAL USER COMMANDS							  MAKE(1L)

NAME

       make - GNU make utility to maintain groups of programs

SYNOPSIS

       make [ -f makefile ] [ option ] ...  target ...

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.texinfo.

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.  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 automati-
       cally 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  begin-
       ning 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.

       -C dir
	    Change to directory dir before reading the makefiles or doing anything else.  If multiple -C options are  specified,  each	is  inter-
	    preted 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.

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

       -f file
	    Use file as a makefile.

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

       -I dir
	    Specifies a directory dir to search for included makefiles.  If several -I options are used to specify several directories, the direc-
	    tories 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
	    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   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

       -l 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.

       -n   Print the commands that would be executed, but do not execute them.

       -o 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 the data base (rules and variable values) that results from reading the makefiles; then execute as usual or as otherwise  speci-
	    fied.   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 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   Eliminate use of the built-in implicit rules.  Also clear out the default list of suffixes for suffix rules.

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

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

       -w   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.

       -W 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 mod-
	    ify  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.

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.

GNU
								  22 August 1989							  MAKE(1L)