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make(1)

NAME

     make -- maintain program dependencies

SYNOPSIS

     make [-BPSXeiknqrstv] [-C directory] [-D variable] [-d flags]
	  [-E variable] [-f makefile] [-I directory] [-j max_jobs]
	  [-m directory] [-V variable] [variable=value] [target ...]

DESCRIPTION

     The make utility is a program designed to simplify the maintenance of
     other programs.  Its input is a list of specifications describing depen-
     dency relationships between the generation of files and programs.	The
     first of BSDmakefile, makefile and Makefile that can be found in either
     the current directory or a special object directory (see .OBJDIR) will be
     read for this list of specifications.  If the file .depend can be found,
     it is also read (see mkdep(1)).

     This manual page is intended as a reference document only.  For a more
     thorough introduction to make and makefiles, please refer to Make - A
     Tutorial.

     The options are as follows:

     -B      Try to be backwards compatible by executing a single shell per
	     command and by executing the commands to make the sources of a
	     dependency line in sequence.  This is turned on by default unless
	     -j is used.

     -C directory
	     Change to directory before reading the makefiles or doing any-
	     thing else.  If multiple -C options are specified, each is inter-
	     preted relative to the previous one: -C / -C etc is equivalent to
	     -C /etc.

     -D variable
	     Define variable to be 1, in the global context.

     -d flags
	     Turn on debugging, and specify which portions of make are to
	     print debugging information.  Argument flags is one or more of
	     the following:

	     A	     Print all possible debugging information; equivalent to
		     specifying all of the debugging flags.

	     a	     Print debugging information about archive searching and
		     caching.

	     c	     Print debugging information about conditional evaluation.

	     d	     Print debugging information about directory searching and
		     caching.

	     f	     Print debugging information about the execution of for
		     loops.

	     g1      Print the input graph before making anything.
		     they are prefixed by @ or other "quiet" flags.  Also
		     known as "loud" behavior.

	     m	     Print debugging information about making targets, includ-
		     ing modification dates.

	     s	     Print debugging information about suffix-transformation
		     rules.

	     t	     Print debugging information about target list mainte-
		     nance.

	     v	     Print debugging information about variable assignment.

     -E variable
	     Specify a variable whose environment value (if any) will override
	     macro assignments within makefiles.

     -e      Specify that environment values override macro assignments within
	     makefiles for all variables.

     -f makefile
	     Specify a makefile to read instead of the default makefile and
	     Makefile.	If makefile is `-', standard input is read.  Multiple
	     makefiles may be specified, and are read in the order specified.

     -I directory
	     Specify a directory in which to search for makefiles and included
	     makefiles.  The system makefile directory (or directories, see
	     the -m option) is automatically included as part of this list.

     -i      Ignore non-zero exit of shell commands in the makefile.  Equiva-
	     lent to specifying `-' before each command line in the makefile.

     -j max_jobs
	     Specify the maximum number of jobs that make may have running at
	     any one time.  Turns compatibility mode off, unless the B flag is
	     also specified.

     -k      Continue processing after errors are encountered, but only on
	     those targets that do not depend on the target whose creation
	     caused the error.

     -m directory
	     Specify a directory in which to search for sys.mk and makefiles
	     included via the <...> style.  Multiple directories can be added
	     to form a search path.  This path will override the default sys-
	     tem include path: /usr/share/mk.  Furthermore, the system include
	     path will be appended to the search path used for "..."-style
	     inclusions (see the -I option).

     -n      Display the commands that would have been executed, but do not
	     actually execute them.

     -P      Collate the output of a given job and display it only when the
	     job finishes, instead of mixing the output of parallel jobs
	     together.	This option has no effect unless -j is used too.

     -s      Do not echo any commands as they are executed.  Equivalent to
	     specifying `@' before each command line in the makefile.

     -t      Rather than re-building a target as specified in the makefile,
	     create it or update its modification time to make it appear up-
	     to-date.

     -V variable
	     Print make's idea of the value of variable, in the global con-
	     text.  Do not build any targets.  Multiple instances of this
	     option may be specified; the variables will be printed one per
	     line, with a blank line for each null or undefined variable.

     -v      Be extra verbose.	For multi-job makes, this will cause file ban-
	     ners to be generated.

     -X      When using the -V option to print the values of variables, do not
	     recursively expand the values.

     variable=value
	     Set the value of the variable variable to value.

     There are seven different types of lines in a makefile: file dependency
     specifications, shell commands, variable assignments, include statements,
     conditional directives, for loops, and comments.

     In general, lines may be continued from one line to the next by ending
     them with a backslash (`\').  The trailing newline character and initial
     whitespace on the following line are compressed into a single space.

FILE DEPENDENCY SPECIFICATIONS

     Dependency lines consist of one or more targets, an operator, and zero or
     more sources.  This creates a relationship where the targets ``depend''
     on the sources and are usually created from them.	The exact relationship
     between the target and the source is determined by the operator that sep-
     arates them.  The three operators are as follows:

     :	   A target is considered out-of-date if its modification time is less
	   than those of any of its sources.  Sources for a target accumulate
	   over dependency lines when this operator is used.  The target is
	   removed if make is interrupted.

     !	   Targets are always re-created, but not until all sources have been
	   examined and re-created as necessary.  Sources for a target accumu-
	   late over dependency lines when this operator is used.  The target
	   is removed if make is interrupted.

     ::    If no sources are specified, the target is always re-created.  Oth-
	   erwise, a target is considered out-of-date if any of its sources
	   has been modified more recently than the target.  Sources for a
	   target do not accumulate over dependency lines when this operator
	   is used.  The target will not be removed if make is interrupted.

     Targets and sources may contain the shell wildcard expressions `?', `*',
     `[]' and `{}'.  The expressions `?', `*' and `[]' may only be used as
     part of the final component of the target or source, and must be used to
     describe existing files.  The expression `{}' need not necessarily be
     used to describe existing files.  Expansion is in directory order, not

     If the first characters of the command line are `@', `-', and/or `+', the
     command is treated specially.  A `@' causes the command not to be echoed
     before it is executed.  A `-' causes any non-zero exit status of the com-
     mand line to be ignored.  A `+' causes the command to be executed even if
     -n is specified on the command line.

VARIABLE ASSIGNMENTS

     Variables in make are much like variables in the shell, and, by tradi-
     tion, consist of all upper-case letters.  The five operators that can be
     used to assign values to variables are as follows:

     =	     Assign the value to the variable.	Any previous value is overrid-
	     den.

     +=      Append the value to the current value of the variable.

     ?=      Assign the value to the variable if it is not already defined.

     :=      Assign with expansion, i.e., expand the value before assigning it
	     to the variable.  Normally, expansion is not done until the vari-
	     able is referenced.

     !=      Expand the value and pass it to the shell for execution and
	     assign the result to the variable.  Any newlines in the result
	     are replaced with spaces.

     Any whitespace before the assigned value is removed; if the value is
     being appended, a single space is inserted between the previous contents
     of the variable and the appended value.

     Variables are expanded by surrounding the variable name with either curly
     braces (`{}') or parentheses (`()') and preceding it with a dollar sign
     (`$').  If the variable name contains only a single letter, the surround-
     ing braces or parentheses are not required.  This shorter form is not
     recommended.

     Variable substitution occurs at two distinct times, depending on where
     the variable is being used.  Variables in dependency lines are expanded
     as the line is read.  Variables in shell commands are expanded when the
     shell command is executed.

     The four different classes of variables (in order of increasing prece-
     dence) are:

     Environment variables
	     Variables defined as part of make's environment.

     Global variables
	     Variables defined in the makefile or in included makefiles.

     Command line variables
	     Variables defined as part of the command line and variables
	     obtained from the MAKEFLAGS environment variable or the
	     .MAKEFLAGS target.

     Local variables
	     Variables that are defined specific to a certain target.  The
		       be transformed (the ``implied'' source); also known as
		       `<'.

	     .MEMBER   The name of the archive member; also known as `%'.

	     .OODATE   The list of sources for this target that were deemed
		       out-of-date; also known as `?'.

	     .PREFIX   The file prefix of the file, containing only the file
		       portion, no suffix or preceding directory components;
		       also known as `*'.

	     .TARGET   The name of the target; also known as `@'.

	     The shorter forms `@', `!', `<', `%', `?', `>', and `*' are per-
	     mitted for backward compatibility and are not recommended.  The
	     six variables `@F', `@D', `<F', `<D', `*F', and `*D' are permit-
	     ted for compatibility with AT&T System V UNIX makefiles and are
	     not recommended.

	     Four of the local variables may be used in sources on dependency
	     lines because they expand to the proper value for each target on
	     the line.	These variables are .TARGET, .PREFIX, .ARCHIVE, and
	     .MEMBER.

     In addition, make sets or knows about the following internal variables or
     environment variables:

     $		     A single dollar sign `$', i.e. `$$' expands to a single
		     dollar sign.

     MAKE	     The name that make was executed with (argv[0]).

     .CURDIR	     A path to the directory where make was executed.  The
		     make utility sets .CURDIR to the canonical path given by
		     getcwd(3).

     .OBJDIR	     A path to the directory where the targets are built.  At
		     startup, make searches for an alternate directory to
		     place target files.  It will attempt to change into this
		     special directory and will search this directory for
		     makefiles not found in the current directory.  The fol-
		     lowing directories are tried in order:

		     1.   ${MAKEOBJDIRPREFIX}/`pwd`
		     2.   ${MAKEOBJDIR}
		     3.   obj.${MACHINE}
		     4.   obj
		     5.   /usr/obj/`pwd`

		     The first directory that make successfully changes into
		     is used.  If either MAKEOBJDIRPREFIX or MAKEOBJDIR is set
		     in the environment but make is unable to change into the
		     corresponding directory, then the current directory is
		     used without checking the remainder of the list.  If they
		     are undefined and make is unable to change into any of
		     the remaining three directories, then the current direc-
		     tory is used.  Note, that MAKEOBJDIRPREFIX and MAKEOBJDIR
		     directives, their names will be automatically appended to
		     the .MAKEFILE_LIST variable.  They are added right before
		     make begins to parse them, so that the name of the cur-
		     rent makefile is the last word in this variable.

     .MAKEFLAGS      The environment variable MAKEFLAGS may contain anything
		     that may be specified on make's command line.  Its con-
		     tents are stored in make's .MAKEFLAGS variable.  All
		     options and variable assignments specified on make's com-
		     mand line are appended to the .MAKEFLAGS variable which
		     is then entered into the environment as MAKEFLAGS for all
		     programs which make executes.

     MFLAGS	     This variable is provided for backward compatibility and
		     contains all the options from the MAKEFLAGS environment
		     variable plus any options specified on make's command
		     line.

     .TARGETS	     List of targets make is currently building.

     .INCLUDES	     See .INCLUDES special target.

     .LIBS	     See .LIBS special target.

     MACHINE	     Name of the machine architecture make is running on,
		     obtained from the MACHINE environment variable, or
		     through uname(3) if not defined.

     MACHINE_ARCH    Name of the machine architecture make was compiled for,
		     defined at compilation time.

     VPATH	     Makefiles may assign a colon-delimited list of directo-
		     ries to VPATH.  These directories will be searched for
		     source files by make after it has finished parsing all
		     input makefiles.

     Variable expansion may be modified to select or modify each word of the
     variable (where a ``word'' is whitespace-delimited sequence of charac-
     ters).  The general format of a variable expansion is as follows:

	   {variable[:modifier[:...]]}

     Each modifier begins with a colon and one of the following special char-
     acters.  The colon may be escaped with a backslash (`\').

     C/pattern/replacement/[1g]
		 Modify each word of the value, substituting every match of
		 the extended regular expression pattern (see re_format(7))
		 with the ed(1)-style replacement string.  Normally, the first
		 occurrence of the pattern in each word of the value is
		 changed.  The `1' modifier causes the substitution to apply
		 to at most one word; the `g' modifier causes the substitution
		 to apply to as many instances of the search pattern as occur
		 in the word or words it is found in.  Note that `1' and `g'
		 are orthogonal; the former specifies whether multiple words
		 are potentially affected, the latter whether multiple substi-
		 tutions can potentially occur within each affected word.

		 The standard shell wildcard characters (`*', `?', and `[]')
		 may be used.  The wildcard characters may be escaped with a
		 backslash (`\').

     Npattern	 This is identical to M, but selects all words which do not
		 match the rest of the modifier.

     O		 Order every word in the variable alphabetically.

     Q		 Quotes every shell meta-character in the variable, so that it
		 can be passed safely through recursive invocations of make.

     R		 Replaces each word in the variable with everything but its
		 suffix.

     S/old_string/new_string/[g]
		 Modify the first occurrence of old_string in each word of the
		 variable's value, replacing it with new_string.  If a `g' is
		 appended to the last slash of the pattern, all occurrences in
		 each word are replaced.  If old_string begins with a caret
		 (`^'), old_string is anchored at the beginning of each word.
		 If old_string ends with a dollar sign (`$'), it is anchored
		 at the end of each word.  Inside new_string, an ampersand
		 (`&') is replaced by old_string.  Any character may be used
		 as a delimiter for the parts of the modifier string.  The
		 anchoring, ampersand, and delimiter characters may be escaped
		 with a backslash (`\').

		 Variable expansion occurs in the normal fashion inside both
		 old_string and new_string with the single exception that a
		 backslash is used to prevent the expansion of a dollar sign
		 (`$'), not a preceding dollar sign as is usual.

     old_string=new_string
		 This is the AT&T System V UNIX style variable substitution.
		 It must be the last modifier specified.  If old_string or
		 new_string do not contain the pattern matching character %
		 then it is assumed that they are anchored at the end of each
		 word, so only suffixes or entire words may be replaced.  Oth-
		 erwise % is the substring of old_string to be replaced in
		 new_string

     T		 Replaces each word in the variable with its last component.

     U		 Converts variable to upper-case letters.

DIRECTIVES, CONDITIONALS, AND FOR LOOPS

     Directives, conditionals, and for loops reminiscent of the C programming
     language are provided in make.  All such structures are identified by a
     line beginning with a single dot (`.') character.	The following direc-
     tives are supported:

     .include <file>

     .include "file"
	     Include the specified makefile.  Variables between the angle
	     brackets or double quotes are expanded to form the file name.  If
	     angle brackets are used, the included makefile is expected to be

     .error message
	     Terminate processing of the makefile immediately.	The filename
	     of the makefile, the line on which the error was encountered and
	     the specified message are printed to the standard error output
	     and make terminates with exit code 1.  Variables in the message
	     are expanded.

     .warning message
	     Emit a warning message.  The filename of the makefile, the line
	     on which the warning was encountered, and the specified message
	     are printed to the standard error output.	Variables in the mes-
	     sage are expanded.

     Conditionals are used to determine which parts of the Makefile to
     process.  They are used similarly to the conditionals supported by the C
     pre-processor.  The following conditionals are supported:

     .if [!]expression [operator expression ...]
	     Test the value of an expression.

     .ifdef [!]variable [operator variable ...]
	     Test the value of a variable.

     .ifndef [!]variable [operator variable ...]
	     Test the value of a variable.

     .ifmake [!]target [operator target ...]
	     Test the target being built.

     .ifnmake [!]target [operator target ...]
	     Test the target being built.

     .else   Reverse the sense of the last conditional.

     .elif [!]expression [operator expression ...]
	     A combination of .else followed by .if.

     .elifdef [!]variable [operator variable ...]
	     A combination of .else followed by .ifdef.

     .elifndef [!]variable [operator variable ...]
	     A combination of .else followed by .ifndef.

     .elifmake [!]target [operator target ...]
	     A combination of .else followed by .ifmake.

     .elifnmake [!]target [operator target ...]
	     A combination of .else followed by .ifnmake.

     .endif  End the body of the conditional.

     The operator may be any one of the following:

     ||     logical OR

     &&     Logical AND; of higher precedence than `||'.

		 the variable has been defined.

     make	 Takes a target name as an argument and evaluates to true if
		 the target was specified as part of make's command line or
		 was declared the default target (either implicitly or explic-
		 itly, see .MAIN) before the line containing the conditional.

     empty	 Takes a variable, with possible modifiers, and evaluates to
		 true if the expansion of the variable would result in an
		 empty string.

     exists	 Takes a file name as an argument and evaluates to true if the
		 file exists.  The file is searched for on the system search
		 path (see .PATH).

     target	 Takes a target name as an argument and evaluates to true if
		 the target has been defined.

     An expression may also be an arithmetic or string comparison, with the
     left-hand side being a variable expansion.  Variable expansion is per-
     formed on both sides of the comparison, after which the integral values
     are compared.  A value is interpreted as hexadecimal if it is preceded by
     0x, otherwise it is decimal; octal numbers are not supported.  The stan-
     dard C relational operators are all supported.  If after variable expan-
     sion, either the left or right hand side of a `==' or `!=' operator is
     not an integral value, then string comparison is performed between the
     expanded variables.  If no relational operator is given, it is assumed
     that the expanded variable is being compared against 0.

     When make is evaluating one of these conditional expressions, and it
     encounters a word it doesn't recognize, either the ``make'' or
     ``defined'' expression is applied to it, depending on the form of the
     conditional.  If the form is .if, .ifdef or .ifndef, the ``defined''
     expression is applied.  Similarly, if the form is .ifmake or .ifnmake,
     the ``make'' expression is applied.

     If the conditional evaluates to true the parsing of the makefile contin-
     ues as before.  If it evaluates to false, the following lines are
     skipped.  In both cases this continues until a .else or .endif is found.

     For loops are typically used to apply a set of rules to a list of files.
     The syntax of a for loop is:

     .for variable in expression
     <make-rules>
     .endfor

     After the for expression is evaluated, it is split into words.  The iter-
     ation variable is successively set to each word, and substituted in the
     make-rules inside the body of the for loop.

COMMENTS

     Comments begin with a hash (`#') character, anywhere but in a shell com-
     mand line, and continue to the end of the line.

SPECIAL SOURCES

     .IGNORE	 Ignore any errors from the commands associated with this tar-
		 get, exactly as if they all were preceded by a dash (`-').

     .OPTIONAL	 If a target is marked with this attribute and make can't fig-
		 ure out how to create it, it will ignore this fact and assume
		 the file isn't needed or already exists.

     .PRECIOUS	 When make is interrupted, it removes any partially made tar-
		 gets.	This source prevents the target from being removed.

     .SILENT	 Do not echo any of the commands associated with this target,
		 exactly as if they all were preceded by an at sign (`@').

     .USE	 Turn the target into make's version of a macro.  When the
		 target is used as a source for another target, the other tar-
		 get acquires the commands, sources, and attributes (except
		 for .USE) of the source.  If the target already has commands,
		 the .USE target's commands are appended to them.

     .WAIT	 If special .WAIT source is appears in a dependency line, the
		 sources that precede it are made before the sources that suc-
		 ceed it in the line.  Loops are not being detected and tar-
		 gets that form loops will be silently ignored.

SPECIAL TARGETS

     Special targets may not be included with other targets, i.e., they must
     be the only target specified.

     .BEGIN	 Any command lines attached to this target are executed before
		 anything else is done.

     .DEFAULT	 This is sort of a .USE rule for any target (that was used
		 only as a source) that make can't figure out any other way to
		 create.  Only the shell script is used.  The .IMPSRC variable
		 of a target that inherits .DEFAULT's commands is set to the
		 target's own name.

     .END	 Any command lines attached to this target are executed after
		 everything else is done.

     .IGNORE	 Mark each of the sources with the .IGNORE attribute.  If no
		 sources are specified, this is the equivalent of specifying
		 the -i option.

     .INCLUDES	 A list of suffixes that indicate files that can be included
		 in a source file.  The suffix must have already been declared
		 with .SUFFIXES; any suffix so declared will have the directo-
		 ries on its search path (see .PATH) placed in the .INCLUDES
		 special variable, each preceded by a -I flag.

     .INTERRUPT  If make is interrupted, the commands for this target will be
		 executed.

     .LIBS	 This does for libraries what .INCLUDES does for include
		 files, except that the flag used is -L.

     .MAIN	 If no target is specified when make is invoked, this target
		 will be built.  This is always set, either explicitly, or
		 implicitly when make selects the default target, to give the
		 user a way to refer to the default target on the command
     .NOTPARALLEL
		 Disable parallel mode.

     .NO_PARALLEL
		 Same as above, for compatibility with other pmake variants.

     .ORDER	 The named targets are made in sequence.

     .PATH	 The sources are directories which are to be searched for
		 files not found in the current directory.  If no sources are
		 specified, any previously specified directories are deleted.
		 Where possible, use of .PATH is preferred over use of the
		 VPATH variable.

     .PATHsuffix
		 The sources are directories which are to be searched for suf-
		 fixed files not found in the current directory.  The make
		 utility first searches the suffixed search path, before
		 reverting to the default path if the file is not found there.
		 This form is required for .LIBS and .INCLUDES to work.

     .PHONY	 Apply the .PHONY attribute to any specified sources.  Targets
		 with this attribute are always considered to be out of date.

     .PRECIOUS	 Apply the .PRECIOUS attribute to any specified sources.  If
		 no sources are specified, the .PRECIOUS attribute is applied
		 to every target in the file.

     .SILENT	 Apply the .SILENT attribute to any specified sources.	If no
		 sources are specified, the .SILENT attribute is applied to
		 every command in the file.

     .SUFFIXES	 Each source specifies a suffix to make.  If no sources are
		 specified, any previous specified suffices are deleted.

COMPATIBILITY

     Older versions of make used MAKE instead of MAKEFLAGS.  This was removed
     for POSIX compatibility.  The internal variable MAKE is set to the same
     value as .MAKE; support for this may be removed in the future.

     Most of the more esoteric features of make should probably be avoided for
     greater compatibility.

ENVIRONMENT

     The make utility uses the following environment variables, if they exist:
     MACHINE, MAKE, MAKEFLAGS, MAKEOBJDIR, and MAKEOBJDIRPREFIX.

FILES

     .depend			 list of dependencies
     Makefile			 list of dependencies
     makefile			 list of dependencies
     obj			 object directory
     sys.mk			 system makefile (processed before any other
				 file, including makefile and Makefile)
     /usr/share/mk		 system makefile directory
     /usr/share/doc/psd/12.make  PMake tutorial
     /usr/obj			 default MAKEOBJDIRPREFIX directory.

     In the presence of several .MAIN special targets, make silently ignores
     all but the first.

     .TARGETS is not set to the default target when make is invoked without a
     target name and no .MAIN special target exists.

     The evaluation of expression in a test is very simple-minded.  Currently,
     the only form that works is `.if ${VAR} op something' For instance, you
     should write tests as `.if ${VAR} == string' not the other way around,
     which would give you an error.

     For loops are expanded before tests, so a fragment such as:

	   .for ARCH in ${SHARED_ARCHS}
	   .if ${ARCH} == ${MACHINE}
		...
	   .endif
	   .endfor

     won't work, and should be rewritten as:

	   .for ARCH in ${SHARED_ARCHS}
	   .if ${MACHINE} == ${ARCH}
		...
	   .endif
	   .endfor

     The parsing code is broken with respect to handling a semicolon after a
     colon, so a fragment like this will fail:

	   HDRS=   foo.h bar.h

	   all:
	   .for h in ${HDRS:S;^;${.CURDIR}/;}
		...
	   .endfor

SEE ALSO

     mkdep(1), make.conf(5)

     PMake - A Tutorial.  in /usr/share/doc/psd/12.make

HISTORY

     A make command appeared in PWB UNIX.

FreeBSD 5.4			August 4, 2004			   FreeBSD 5.4

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