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MAKE(1)			FreeBSD	General	Commands Manual		       MAKE(1)

NAME
     make -- maintain program dependencies

SYNOPSIS
     make [-ABPSXeiknpqrstv] [-C directory] [-D	variable] [-d flags]
	  [-E variable]	[-f makefile] [-I directory] [-j max_jobs]
	  [-m directory] [-V variable] [-x warning_options] [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.

     First of all, the initial list of specifications will be read from	the
     system makefile, sys.mk, unless inhibited with the	-r option.  The	stan-
     dard sys.mk as shipped with FreeBSD also handles make.conf(5), the
     default path to which can be altered via the make variable	__MAKE_CONF.

     Then the first of BSDmakefile, makefile, and Makefile that	can be found
     in	the current directory, object directory	(see .OBJDIR), or search path
     (see the -I option) will be read for the main list	of dependency specifi-
     cations.  A different makefile or list of them can	be supplied via	the -f
     option(s).	 Finally, if the file .depend can be found in any of the
     aforesaid locations, it will also be read (see mkdep(1)).

     When make searches	for a makefile,	its name takes precedence over its
     location.	For instance, BSDmakefile in the object	directory will be
     favored over Makefile in the current directory.

     The options are as	follows:

     -A	     Make archive errors non-fatal, causing make to just skip the
	     remainder or all of the archive and continue after	printing a
	     message.

     -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.

	     g2	     Print the input graph after making	everything, or before
		     exiting on	error.

	     j	     Print debugging information about running multiple
		     shells.

	     l	     Print commands in Makefiles regardless of whether or not
		     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 one.  If
	     makefile is not an	absolute pathname, make	will search for	it as
	     described above.  In case makefile	is `-',	standard input is
	     read.  Multiple -f	options	can be supplied, and the makefiles
	     will be read in that order.  Unlike the other command-line
	     options, -f is neither stored in .MAKEFLAGS nor pushed down to
	     sub-makes via MAKEFLAGS.  See below for more details on these
	     variables.

     -I	directory
	     Specify a directory in which to search for	makefiles and included
	     makefiles.	 Multiple -I options can be specified to form a	search
	     path.  The	system makefile	directory (or directories, see the -m
	     option) is	automatically appended at the tail of this path.

     -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	the system makefile
	     and makefiles included via	the <...> style.  Multiple -m options
	     can be specified to form a	search path.  This path	will override
	     the default system	include	path, /usr/share/mk.  The system
	     include path will always be appended to the search	path used for
	     "..."-style inclusions and	makefile searches (see the -I option).

	     If	a file or directory name in the	-m argument (or	the
	     MAKESYSPATH environment variable) starts with the string ".../"
	     then make will search for the specified file or directory named
	     in	the remaining part of the argument string.  The	search starts
	     with the current directory	of the Makefile	and then works upward
	     towards the root of the filesystem.  If the search	is successful,
	     then the resulting	directory replaces the ".../" specification in
	     the -m argument.  If used,	this feature allows make to easily
	     search in the current source tree for customized sys.mk files
	     (e.g. by using ".../mk/sys.mk" as an argument).  Note that	a -C
	     that are earlier on the command line affect where -m ".../"
	     searches.

     -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.

     -p	     Only print	the input graph, not executing any commands.  The out-
	     put is the	same as	-d g1.	When combined with -f /dev/null, only
	     the builtin rules of make are displayed.

     -Q	     Be	extra quiet.  For multi-job makes, this	will cause file	ban-
	     ners not to be generated.

     -q	     Do	not execute any	commands, but exit 0 if	the specified targets
	     are up-to-date and	1, otherwise.

     -r	     Do	not process the	system makefile.

     -S	     Stop processing when an error is encountered.  Default behaviour.
	     This is needed to negate the -k option during recursive builds.

     -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.  If
	     variable contains a `$' then the value will be expanded before
	     printing.

     -v	     Be	extra verbose.	Print any extra	information.

     -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.

     -x	warning_options
	     Specify extended warning options.	This option may	be specified
	     several times.  A warning_option can be prefixed with ``no'' in
	     which case	the warning is switched	off.  The currently available
	     options are:

	     dirsyntax
		     Warn if anything except blanks and	comments follows an
		     .endif or .else directive.

	     See also the .WARN	special	target.

     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
     alphabetically as done in the shell.

SHELL COMMANDS
     Each target may have associated with it a series of shell commands, nor-
     mally used	to create the target.  Each of the commands in this script
     must be preceded by a tab.	 While any target may appear on	a dependency
     line, only	one of these dependencies may be followed by a creation
     script, unless the	`::' operator is used.

     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.

     If	the name of an environment variable appears in a makefile on the left-
     hand side of an assignment, a global variable with	the same name is cre-
     ated, and the latter shadows the former as	per their relative prece-
     dences.  The environment is not changed in	this case, and the change is
     not exported to programs executed by make.	 However, a command-line vari-
     able actually replaces the	environment variable of	the same name if the
     latter exists, which is visible to	child programs.

     There are seven local variables in	make:

     .ALLSRC   The list	of all sources for this	target;	also known as `_'.

     .ARCHIVE  The name	of the archive file; also known	as `!'.

     .IMPSRC   The name/path of	the source from	which the target is to 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 permitted for
     backward compatibility and	are not	recommended.  The six variables	`@F',
     `@D', `_F', `_D', `*F', and `*D' are permitted 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 -P`
		     2.	  ${MAKEOBJDIR}
		     3.	  obj.${MACHINE}
		     4.	  obj
		     5.	  /usr/obj/`pwd	-P`

		     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
		     must be environment variables and should not be set on
		     make's command line.

		     The make utility sets .OBJDIR to the canonical path given
		     by	getcwd(3).

     .MAKEFILE_LIST  As	make reads various makefiles, including	the default
		     files and any obtained from the command line and .include
		     and .sinclude directives, their names will	be automati-
		     cally appended to the .MAKEFILE_LIST variable.  They are
		     added right before	make begins to parse them, so that the
		     name of the current makefile is the last word in this
		     variable.

     MAKEFLAGS	     The environment variable MAKEFLAGS	may initially contain
		     anything that may be specified on make's command line,
		     including -f option(s).  After processing,	its contents
		     are stored	in the .MAKEFLAGS global variable, although
		     any -f options are	omitted.  Then all options and vari-
		     able assignments specified	on make's command line,	except
		     for -f, are appended to the .MAKEFLAGS variable.

		     Whenever make executes a program, it sets MAKEFLAGS in
		     the program's environment to the current value of the
		     .MAKEFLAGS	global variable.  Thus,	if MAKEFLAGS in	make's
		     environment contains any -f options, they will not	be
		     pushed down to child programs automatically.  The make
		     utility effectively filters out -f	options	from the envi-
		     ronment and command line although it passes the rest of
		     its options down to sub-makes via MAKEFLAGS by default.

		     When passing macro	definitions and	flag arguments in the
		     MAKEFLAGS environment variable, space and tab characters
		     are quoted	by preceding them with a backslash.  When
		     reading the MAKEFLAGS variable from the environment, all
		     sequences of a backslash and one of space or tab are
		     replaced just with	their second character without causing
		     a word break.  Any	other occurrences of a backslash are
		     retained.	Groups of unquoted space, tab and newline
		     characters	cause word breaking.

     .MAKEFLAGS	     Initially,	this global variable contains make's current
		     run-time options from the environment and command line as
		     described above, under MAKEFLAGS.	By modifying the con-
		     tents of the .MAKEFLAGS global variable, the makefile can
		     alter the contents	of the MAKEFLAGS environment variable
		     made available for	all programs which make	executes.
		     This includes adding -f option(s).	 The current value of
		     .MAKEFLAGS	is just	copied verbatim	to MAKEFLAGS in	the
		     environment of child programs.

		     Note that any options entered to .MAKEFLAGS neither
		     affect the	current	instance of make nor show up in	its
		     own copy of MAKEFLAGS instantly.  However,	they do	show
		     up	in the MAKEFLAGS environment variable of programs exe-
		     cuted by make.  On	the other hand,	a direct assignment to
		     MAKEFLAGS neither affects the current instance of make
		     nor is passed down	to make's children.  Compare with the
		     .MAKEFLAGS	special	target below.

     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.

     .MAKE.PID	     The process-id of make.

     .MAKE.PPID	     The parent	process-id of make.

     .MAKE.JOB.PREFIX
		     If	make is	run with -j -v then output for each target is
		     prefixed with a token `---	target ---' the	first part of
		     which can be controlled via .MAKE.JOB.PREFIX.
		     For example:
		     .MAKE.JOB.PREFIX=${.newline}---${MAKE:T}[${.MAKE.PID}]
		     would produce tokens like `---make[1234] target ---' or
		     .MAKE.JOB.PREFIX=---pid[${.MAKE.PID}],ppid[${.MAKE.PPID}]
		     would produce tokens like `---pid[56789],ppid[1234]
		     target ---' making	it easier to track the degree of par-
		     allelism being achieved.

     .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 Modifiers
     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.

     :E		 Replaces each word in the variable with its suffix.

     :H		 Replaces each word in the variable with everything but	the
		 last component.

     :L		 Converts variable to lower-case letters.  (deprecated)

     :Mpattern	 Select	only those words that match the	rest of	the modifier.
		 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.

     :tl	 Converts variable to lower-case letters.

     :tu	 Converts variable to upper-case letters.

     :U		 Converts variable to upper-case letters.  (deprecated)

     :u		 Remove	adjacent duplicate words (like uniq(1)).

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
	     in	the system makefile directory.	If double quotes are used, the
	     including makefile's directory and	any directories	specified
	     using the -I option are searched before the system	makefile
	     directory.

     .sinclude _file_

     .sinclude "file"
	     Like .include, but	silently ignored if the	file cannot be found
	     and opened.

     .undef variable
	     Un-define the specified global variable.  Only global variables
	     may be un-defined.

     .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 `||'.

     As	in C, make will	only evaluate a	conditional as far as is necessary to
     determine its value.  Parentheses may be used to change the order of
     evaluation.  The boolean operator `!' may be used to logically negate an
     entire conditional.  It is	of higher precedence than `&&'.

     The value of expression may be any	of the following:

     defined	 Takes a variable name as an argument and evaluates to true if
		 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 a numeric or string comparison: in this case,
     the left-hand side	must be	a variable expansion, whereas the right-hand
     side can be a constant or a variable expansion.  Variable expansion is
     performed on both sides, after which the resulting	values are compared.
     A value is	interpreted as hexadecimal if it is preceded by	0x, otherwise
     it	is decimal; octal numbers are not supported.

     String comparison can only	use the	`==' or	`!=' operators,	whereas
     numeric values (both integer and floating point) can also be compared
     using the `>', `>=', `<' and `<=' operators.

     If	no relational operator (and right-hand value) are given, an implicit
     `!= 0' is used.  However be very careful in using this feature especially
     when the left-hand	side variable expansion	returns	a string.

     When make is evaluating one of these conditional expressions, and it
     encounters	a word it does not 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 (`-').

     .MAKE	 Execute the commands associated with this target even if the
		 -n or -t options were specified.  Normally used to mark
		 recursive make's.

     .NOTMAIN	 Normally make selects the first target	it encounters as the
		 default target	to be built if no target was specified.	 This
		 source	prevents this target from being	selected.

     .OPTIONAL	 If a target is	marked with this attribute and make cannot
		 figure	out how	to create it, it will ignore this fact and
		 assume	the file is not	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 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 cannot figure out any other way
		 to create.  Only the shell script is used.  The .IMPSRC vari-
		 able 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
		 line.

     .MAKEFILEDEPS
		 Enable	the ``Remaking Makefiles'' functionality, as explained
		 in the	REMAKING MAKEFILES section below.

     .MAKEFLAGS	 This target provides a	way to specify flags for make when the
		 makefile is used.  The	flags are as if	typed to the shell,
		 though	the -f option will have	no effect.  Flags (except for
		 -f) and variable assignments specified	as the source for this
		 target	are also appended to the .MAKEFLAGS internal variable.
		 Please	note the difference between this target	and the
		 .MAKEFLAGS internal variable: specifying an option or vari-
		 able assignment as the	source for this	target will affect
		 both the current makefile and all processes that make exe-
		 cutes.

     .MFLAGS	 Same as above,	for backward compatibility.

     .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.

     .POSIX	 Adjust	make's behavior	to match the applicable	POSIX specifi-
		 cations.  (Note this disables the ``Remaking Makefiles'' fea-
		 ture.)

     .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.

     .SHELL	 Select	another	shell.	The sources of this target have	the
		 format	key=value.  The	key is one of:

		 path	    Specify the	path to	the new	shell.

		 name	    Specify the	name of	the new	shell.	This may be
			    either one of the three builtin shells (see	below)
			    or any other name.

		 quiet	    Specify the	shell command to turn echoing off.

		 echo	    Specify the	shell command to turn echoing on.

		 filter	    Usually shells print the echo off command before
			    turning echoing off.  This is the exact string
			    that will be printed by the	shell and is used to
			    filter the shell output to remove the echo off
			    command.

		 echoFlag   The	shell option that turns	echoing	on.

		 errFlag    The	shell option to	turn on	error checking.	 If
			    error checking is on, the shell should exit	if a
			    command returns a non-zero status.

		 hasErrCtl  True if the	shell has error	control.

		 check	    If hasErrCtl is true then this is the shell	com-
			    mand to turn error checking	on.  If	hasErrCtl is
			    false then this is a command template to echo com-
			    mands for which error checking is disabled.	 The
			    template must contain a `%s'.

		 ignore	    If hasErrCtl is true, this is the shell command to
			    turn error checking	off.  If hasErrCtl is false,
			    this is a command template to execute a command so
			    that errors	are ignored.  The template must	con-
			    tain a `%s'.

		 meta	    This is a string of	meta characters	of the shell.

		 builtins   This is a string holding all the shell's builtin
			    commands separated by blanks.  The meta and
			    builtins strings are used in compat	mode.  When a
			    command line contains neither a meta character nor
			    starts with	a shell	builtin, it is executed
			    directly without invoking a	shell.	When one of
			    these strings (or both) is empty all commands are
			    executed through a shell.

		 unsetenv   If true, remove the	ENV environment	variable
			    before executing any command.  This	is useful for
			    the	Korn-shell (ksh).

		 Values	that are strings must be surrounded by double quotes.
		 Boolean values	are specified as `T' or	`Y' (in	either case)
		 to mean true.	Any other value	is taken to mean false.

		 There are several uses	of the .SHELL target:

		 +o   Selecting one of the builtin shells.  This	is done	by
		     just specifying the name of the shell with	the name key-
		     word.  It is also possible	to modify the parameters of
		     the builtin shell by just specifying other	keywords
		     (except for path).

		 +o   Using another executable for one of the builtin shells.
		     This is done by specifying	the path to the	executable
		     with the path keyword.  If	the last component is the same
		     as	the name of the	builtin	shell, no name needs to	be
		     specified;	if it is different, the	name must be given:

			   .SHELL: path="/usr/local/bin/sh"

		     selects the builtin shell ``sh'' but will execute it from
		     /usr/local/bin/sh.	 Like in the previous case, it is pos-
		     sible to modify parameters	of the builtin shell by	just
		     specifying	them.

		 +o   Using an entirely different shell.	 This is done by spec-
		     ifying all	keywords.

		 The builtin shells are	``sh'',	``csh''	and ``ksh''.  Because
		 FreeBSD has no	ksh in /bin, it	is unwise to specify
		 name="ksh" without also specifying a path.

     .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 suffixes are	deleted.

     .WARN	 Each source specifies a warning flag as previously described
		 for the -x command line option.  Warning flags	specified on
		 the command line take precedence over flags specified in the
		 makefile.  Also, command line warning flags are pushed	to
		 sub-makes through the MAKEFLAGS environment variables so that
		 a warning flag	specified on the command line will influence
		 all sub-makes.	 Several flags can be specified	on a single
		 .WARN target by separating them with blanks.

REMAKING MAKEFILES
     If	the special target .MAKEFILEDEPS exists	in the Makefile, make enables
     the ``Remaking Makefiles''	feature.  After	reading	Makefile and all the
     files that	are included using .include or .sinclude directives (source
     Makefiles)	make considers each source Makefile as a target	and tries to
     rebuild it.  Both explicit	and implicit rules are checked and all source
     Makefiles are updated if necessary. If any	of the source Makefiles	were
     rebuilt, make restarts from clean state.

     To	prevent	infinite loops the following source Makefile targets are
     ignored:

     +o	 :: targets that have no prerequisites

     +o	 !  targets

     +o	 targets that have .PHONY or .EXEC attributes

     +o	 targets without prerequisites and without commands

     When remaking a source Makefile options -t	(touch target),	-q (query
     mode), and	-n (no exec) do	not take effect, unless	source Makefile	is
     specified explicitly as a target in make command line.

     Additionally, system makefiles and	.depend	are not	considered as Make-
     files that	can be rebuilt.

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

FILES
     .depend			 list of dependencies
     Makefile			 list of dependencies
     makefile			 list of dependencies
     obj			 object	directory
     sys.mk			 system	makefile
     /usr/share/mk		 default system	makefile directory
     /usr/share/doc/psd/12.make	 PMake tutorial
     /usr/obj			 default MAKEOBJDIRPREFIX directory.
     /etc/make.conf		 default path to make.conf(5)

EXAMPLES
     List all included makefiles in order visited:

	   make	-V .MAKEFILE_LIST | tr \  \\n

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.

     The use of	the :L and :U modifiers	will be	deprecated in FreeBSD 10.0 and
     the more portable (among Pmake decedents) :tl and :tu should be used
     instead.

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

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.

BUGS
     The determination of .OBJDIR is contorted to the point of absurdity.

     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

     will not 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

     A trailing	backslash in a variable	value defined on the command line
     causes the	delimiting space in the	MAKEFLAGS environment variable to be
     preceded by that backslash.  That causes a	submake	to not treat that
     space as a	word delimiter.	 Fixing	this requires a	larger rewrite of the
     code handling command line	macros and assignments to .MAKEFLAGS.

FreeBSD	10.1			 May 30, 2012			  FreeBSD 10.1

NAME | SYNOPSIS | DESCRIPTION | FILE DEPENDENCY SPECIFICATIONS | SHELL COMMANDS | VARIABLE ASSIGNMENTS | DIRECTIVES, CONDITIONALS, AND FOR LOOPS | COMMENTS | SPECIAL SOURCES | SPECIAL TARGETS | REMAKING MAKEFILES | ENVIRONMENT | FILES | EXAMPLES | COMPATIBILITY | SEE ALSO | HISTORY | BUGS

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