1 .\" $NetBSD: make.1,v 1.315 2022/07/12 23:47:00 rillig Exp $
3 .\" Copyright (c) 1990, 1993
4 .\" The Regents of the University of California. All rights reserved.
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7 .\" modification, are permitted provided that the following conditions
9 .\" 1. Redistributions of source code must retain the above copyright
10 .\" notice, this list of conditions and the following disclaimer.
11 .\" 2. Redistributions in binary form must reproduce the above copyright
12 .\" notice, this list of conditions and the following disclaimer in the
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14 .\" 3. Neither the name of the University nor the names of its contributors
15 .\" may be used to endorse or promote products derived from this software
16 .\" without specific prior written permission.
18 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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30 .\" from: @(#)make.1 8.4 (Berkeley) 3/19/94
37 .Nd maintain program dependencies
56 is a program designed to simplify the maintenance of other programs.
57 Its input is a list of specifications as to the files upon which programs
58 and other files depend.
61 makefile option is given,
67 in order to find the specifications.
70 exists, it is read (see
73 This manual page is intended as a reference document only.
74 For a more thorough description of
76 and makefiles, please refer to
77 .%T "PMake \- A Tutorial" .
80 will prepend the contents of the
82 environment variable to the command line arguments before parsing them.
84 The options are as follows:
87 Try to be backwards compatible by executing a single shell per command and
88 by executing the commands to make the sources of a dependency line in sequence.
92 before reading the makefiles or doing anything else.
95 options are specified, each is interpreted relative to the previous one:
96 .Fl C Pa / Fl C Pa etc
102 to be 1, in the global scope.
104 Turn on debugging, and specify which portions of
106 are to print debugging information.
107 Unless the flags are preceded by
109 they are added to the
111 environment variable and will be processed by any child make processes.
112 By default, debugging information is printed to standard error,
113 but this can be changed using the
116 The debugging output is always unbuffered; in addition, if debugging
117 is enabled but debugging output is not directed to standard output,
118 then the standard output is line buffered.
120 is one or more of the following:
123 Print all possible debugging information;
124 equivalent to specifying all of the debugging flags.
126 Print debugging information about archive searching and caching.
128 Print debugging information about current working directory.
130 Print debugging information about conditional evaluation.
132 Print debugging information about directory searching and caching.
134 Print debugging information about failed commands and targets.
135 .It Ar F Ns Oo Sy \&+ Oc Ns Ar filename
136 Specify where debugging output is written.
137 This must be the last flag, because it consumes the remainder of
139 If the character immediately after the
143 then the file will be opened in append mode;
144 otherwise the file will be overwritten.
149 then debugging output will be written to the
150 standard output or standard error output file descriptors respectively
153 option has no effect).
154 Otherwise, the output will be written to the named file.
155 If the file name ends
159 is replaced by the pid.
161 Print debugging information about loop evaluation.
163 Print the input graph before making anything.
165 Print the input graph after making everything, or before exiting
168 Print the input graph before exiting on error.
170 Print debugging information about hash table operations.
172 Print debugging information about running multiple shells.
175 This will throw errors for variable assignments that do not parse
176 correctly, at the time of assignment so the file and line number
179 Print commands in Makefiles regardless of whether or not they are prefixed by
181 or other "quiet" flags.
182 Also known as "loud" behavior.
184 Print debugging information about "meta" mode decisions about targets.
186 Print debugging information about making targets, including modification
189 Don't delete the temporary command scripts created when running commands.
190 These temporary scripts are created in the directory
193 environment variable, or in
197 is unset or set to the empty string.
198 The temporary scripts are created by
200 and have names of the form
203 This can create many files in
209 Print debugging information about makefile parsing.
211 Print debugging information about suffix-transformation rules.
213 Print debugging information about target list maintenance.
217 option to print raw values of variables, overriding the default behavior
219 .Va .MAKE.EXPAND_VARIABLES .
221 Print debugging information about variable assignment.
223 Run shell commands with
225 so the actual commands are printed as they are executed.
228 Specify that environment variables override macro assignments within
231 Specify a makefile to read instead of the default
237 standard input is read.
238 Multiple makefiles may be specified, and are read in the order specified.
239 .It Fl I Ar directory
240 Specify a directory in which to search for makefiles and included makefiles.
241 The system makefile directory (or directories, see the
243 option) is automatically included as part of this list.
245 Ignore non-zero exit of shell commands in the makefile.
246 Equivalent to specifying
248 before each command line in the makefile.
252 be specified by the user.
256 option is in use in a recursive build, this option is passed by a make
257 to child makes to allow all the make processes in the build to
258 cooperate to avoid overloading the system.
260 Specify the maximum number of jobs that
262 may have running at any one time.
263 The value is saved in
265 Turns compatibility mode off, unless the
267 option is also specified.
268 When compatibility mode is off, all commands associated with a
269 target are executed in a single shell invocation as opposed to the
270 traditional one shell invocation per line.
271 This can break traditional scripts which change directories on each
272 command invocation and then expect to start with a fresh environment
274 It is more efficient to correct the scripts rather than turn backwards
277 Continue processing after errors are encountered, but only on those targets
278 that do not depend on the target whose creation caused the error.
279 .It Fl m Ar directory
280 Specify a directory in which to search for sys.mk and makefiles included
282 .Li \&< Ns Ar file Ns Li \&> Ns -style
286 option can be used multiple times to form a search path.
287 This path will override the default system include path: /usr/share/mk.
288 Furthermore the system include path will be appended to the search path used
290 .Li \*q Ns Ar file Ns Li \*q Ns -style
291 include statements (see the
295 If a file or directory name in the
299 environment variable) starts with the string
303 will search for the specified file or directory named in the remaining part
304 of the argument string.
305 The search starts with the current directory of
306 the Makefile and then works upward towards the root of the file system.
307 If the search is successful, then the resulting directory replaces the
312 If used, this feature allows
314 to easily search in the current source tree for customized sys.mk files
319 Display the commands that would have been executed, but do not
320 actually execute them unless the target depends on the .MAKE special
321 source (see below) or the command is prefixed with
324 Display the commands which would have been executed, but do not
325 actually execute any of them; useful for debugging top-level makefiles
326 without descending into subdirectories.
328 Do not execute any commands, but exit 0 if the specified targets are
329 up-to-date and 1, otherwise.
331 Do not use the built-in rules specified in the system makefile.
333 Stop processing if an error is encountered.
334 This is the default behavior and the opposite of
337 Do not echo any commands as they are executed.
338 Equivalent to specifying
340 before each command line in the makefile.
341 .It Fl T Ar tracefile
345 append a trace record to
347 for each job started and completed.
349 Rather than re-building a target as specified in the makefile, create it
350 or update its modification time to make it appear up-to-date.
354 Do not build any targets.
355 Multiple instances of this option may be specified;
356 the variables will be printed one per line,
357 with a blank line for each null or undefined variable.
358 The value printed is extracted from the global scope after all
359 makefiles have been read.
360 By default, the raw variable contents (which may
361 include additional unexpanded variable references) are shown.
366 then the value will be recursively expanded to its complete resultant
367 text before printing.
368 The expanded value will also be printed if
369 .Va .MAKE.EXPAND_VARIABLES
373 option has not been used to override it.
374 Note that loop-local and target-local variables, as well as values
375 taken temporarily by global variables during makefile processing, are
376 not accessible via this option.
379 debug mode can be used to see these at the cost of generating
380 substantial extraneous output.
384 but the variable is always expanded to its complete value.
386 Treat any warnings during makefile parsing as errors.
388 Print entering and leaving directory messages, pre and post processing.
390 Don't export variables passed on the command line to the environment
392 Variables passed on the command line are still exported
395 environment variable.
396 This option may be useful on systems which have a small limit on the
397 size of command arguments.
398 .It Ar variable=value
399 Set the value of the variable
403 Normally, all values passed on the command line are also exported to
404 sub-makes in the environment.
407 flag disables this behavior.
408 Variable assignments should follow options for POSIX compatibility
409 but no ordering is enforced.
412 There are seven different types of lines in a makefile: file dependency
413 specifications, shell commands, variable assignments, include statements,
414 conditional directives, for loops, and comments.
416 In general, lines may be continued from one line to the next by ending
417 them with a backslash
419 The trailing newline character and initial whitespace on the following
420 line are compressed into a single space.
421 .Sh FILE DEPENDENCY SPECIFICATIONS
422 Dependency lines consist of one or more targets, an operator, and zero
424 This creates a relationship where the targets
427 and are customarily created from them.
428 A target is considered out-of-date if it does not exist, or if its
429 modification time is less than that of any of its sources.
430 An out-of-date target will be re-created, but not until all sources
431 have been examined and themselves re-created as needed.
432 Three operators may be used:
435 Many dependency lines may name this target but only one may have
436 attached shell commands.
437 All sources named in all dependency lines are considered together,
438 and if needed the attached shell commands are run to create or
439 re-create the target.
442 is interrupted, the target is removed.
444 The same, but the target is always re-created whether or not it is out
447 Any dependency line may have attached shell commands, but each one
448 is handled independently: its sources are considered and the attached
449 shell commands are run if the target is out of date with respect to
450 (only) those sources.
451 Thus, different groups of the attached shell commands may be run
452 depending on the circumstances.
455 for dependency lines with no sources, the attached shell
456 commands are always run.
459 the target will not be removed if
463 All dependency lines mentioning a particular target must use the same
466 Targets and sources may contain the shell wildcard values
477 may only be used as part of the final
478 component of the target or source, and must be used to describe existing
482 need not necessarily be used to describe existing files.
483 Expansion is in directory order, not alphabetically as done in the shell.
485 Each target may have associated with it one or more lines of shell
487 used to create the target.
488 Each of the lines in this script
490 be preceded by a tab.
491 (For historical reasons, spaces are not accepted.)
492 While targets can appear in many dependency lines if desired, by
493 default only one of these rules may be followed by a creation
497 operator is used, however, all rules may include scripts and the
498 scripts are executed in the order found.
500 Each line is treated as a separate shell command, unless the end of
501 line is escaped with a backslash
503 in which case that line and the next are combined.
504 .\" The escaped newline is retained and passed to the shell, which
505 .\" normally ignores it.
506 .\" However, the tab at the beginning of the following line is removed.
507 If the first characters of the command are any combination of
512 the command is treated specially.
515 causes the command not to be echoed before it is executed.
518 causes the command to be executed even when
521 This is similar to the effect of the .MAKE special source,
522 except that the effect can be limited to a single line of a script.
525 in compatibility mode
526 causes any non-zero exit status of the command line to be ignored.
530 is run in jobs mode with
532 the entire script for the target is fed to a
533 single instance of the shell.
534 In compatibility (non-jobs) mode, each command is run in a separate process.
535 If the command contains any shell meta characters
536 .Pq Ql #=|^(){};&<>*?[]:$`\e\en
537 it will be passed to the shell; otherwise
539 will attempt direct execution.
540 If a line starts with
542 and the shell has ErrCtl enabled then failure of the command line
543 will be ignored as in compatibility mode.
546 affects the entire job;
547 the script will stop at the first command line that fails,
548 but the target will not be deemed to have failed.
550 Makefiles should be written so that the mode of
552 operation does not change their behavior.
553 For example, any command which needs to use
557 without potentially changing the directory for subsequent commands
558 should be put in parentheses so it executes in a subshell.
559 To force the use of one shell, escape the line breaks so as to make
560 the whole script one command.
562 .Bd -literal -offset indent
563 avoid-chdir-side-effects:
564 @echo Building $@ in `pwd`
565 @(cd ${.CURDIR} && ${MAKE} $@)
568 ensure-one-shell-regardless-of-mode:
569 @echo Building $@ in `pwd`; \e
570 (cd ${.CURDIR} && ${MAKE} $@); \e
580 before executing any targets, each child process
581 starts with that as its current working directory.
582 .Sh VARIABLE ASSIGNMENTS
583 Variables in make behave much like macros in the C preprocessor.
585 Variable assignments have the form
586 .Sq Ar NAME Ar op Ar value ,
590 is a single-word variable name,
591 consisting, by tradition, of all upper-case letters,
593 is one of the five variable assignment operators described below, and
595 is interpreted according to the variable assignment operator.
604 .Ss Variable assignment operators
605 The five operators that can be used to assign values to variables are:
608 Assign the value to the variable.
609 Any previous value is overwritten.
611 Append the value to the current value of the variable,
612 separating them by a single space.
614 Assign the value to the variable if it is not already defined.
616 Assign with expansion, i.e. expand the value before assigning it
618 Normally, expansion is not done until the variable is referenced.
621 References to undefined variables are
624 This can cause problems when variable modifiers are used.
626 Expand the value and pass it to the shell for execution and assign
627 the result to the variable.
628 Any newlines in the result are replaced with spaces.
630 .Ss Expansion of variables
631 In contexts where variables are expanded,
633 expands to a single dollar sign.
634 References to variables have the form
635 .Ql \&${ Ns Ar name Ns Oo \&: Ns Ar modifiers Oc Ns }
637 .Ql \&$( Ns Ar name Ns Oo \&: Ns Ar modifiers Oc Ns ) .
638 If the variable name contains only a single character,
639 the surrounding curly braces or parentheses are not required.
640 This shorter form is not recommended.
642 If the variable name contains a dollar, then the name itself is expanded first.
643 This allows almost arbitrary variable names, however names containing dollar,
644 braces, parentheses, or whitespace are really best avoided.
646 If the result of expanding a variable contains a dollar sign
648 the string is expanded again.
650 Variable substitution occurs at four distinct times, depending on where
651 the variable is being used.
654 Variables in dependency lines are expanded as the line is read.
656 Variables in conditionals are expanded individually,
657 but only as far as necessary to determine the result of the conditional.
659 Variables in shell commands are expanded when the shell command is
663 loop index variables are expanded on each loop iteration.
664 Note that other variables are not expanded when composing the body of a loop,
665 so the following example code:
666 .Bd -literal -offset indent
680 .Bd -literal -offset indent
685 Because while ${a} contains
687 after the loop is executed, ${b}
692 since after the loop completes ${j} contains
696 The four different classes of variables (in order of increasing precedence)
699 .It Environment variables
700 Variables defined as part of
704 Variables defined in the makefile or in included makefiles.
705 .It Command line variables
706 Variables defined as part of the command line.
708 Variables that are defined specific to a certain target.
711 Local variables can be set on a dependency line, if
712 .Va .MAKE.TARGET_LOCAL_VARIABLES
716 (which will already have had global variables expanded)
717 is the variable value.
719 .Bd -literal -offset indent
720 COMPILER_WRAPPERS= ccache distcc icecc
722 ${OBJS}: .MAKE.META.CMP_FILTER=${COMPILER_WRAPPERS:S,^,N,}
727 will be impacted by that filter (in "meta" mode) and
728 simply enabling/disabling any of the compiler wrappers will not render all
729 of those targets out-of-date.
732 target-local variable assignments behave differently in that;
733 .Bl -tag -width Ds -offset indent
735 Only appends to a previous local assignment
736 for the same target and variable.
738 Is redundant with respect to global variables,
739 which have already been expanded.
742 The seven built-in local variables are as follows:
743 .Bl -tag -width ".ARCHIVE" -offset indent
745 The list of all sources for this target; also known as
748 The name of the archive file; also known as
751 In suffix-transformation rules, the name/path of the source from which the
752 target is to be transformed (the
754 source); also known as
756 It is not defined in explicit rules.
758 The name of the archive member; also known as
761 The list of sources for this target that were deemed out-of-date; also
765 The file prefix of the target, containing only the file portion, no suffix
766 or preceding directory components; also known as
768 The suffix must be one of the known suffixes declared with
770 or it will not be recognized.
772 The name of the target; also known as
774 For compatibility with other makes this is an alias for
776 in archive member rules.
788 are permitted for backward
789 compatibility with historical makefiles and legacy POSIX make and are
792 Variants of these variables with the punctuation followed immediately by
798 are legacy forms equivalent to using the
803 These forms are accepted for compatibility with
805 makefiles and POSIX but are not recommended.
807 Four of the local variables may be used in sources on dependency lines
808 because they expand to the proper value for each target on the line.
815 .Ss Additional built-in variables
818 sets or knows about the following variables:
819 .Bl -tag -width .MAKEOVERRIDES
821 The list of all targets encountered in the Makefile.
823 Makefile parsing, lists only those targets encountered thus far.
825 A path to the directory where
828 Refer to the description of
831 .It Va .INCLUDEDFROMDIR
832 The directory of the file this Makefile was included from.
833 .It Va .INCLUDEDFROMFILE
834 The filename of the file this Makefile was included from.
845 The preferred variable to use is the environment variable
847 because it is more compatible with other versions of
849 and cannot be confused with the special target with the same name.
850 .It Va .MAKE.DEPENDFILE
851 Names the makefile (default
853 from which generated dependencies are read.
854 .It Va .MAKE.EXPAND_VARIABLES
855 A boolean that controls the default behavior of the
858 If true, variable values printed with
860 are fully expanded; if false, the raw variable contents (which may
861 include additional unexpanded variable references) are shown.
862 .It Va .MAKE.EXPORTED
863 The list of variables exported by
869 .It Va .MAKE.JOB.PREFIX
874 the output for each target is prefixed with a token
876 the first part of which can be controlled via
877 .Va .MAKE.JOB.PREFIX .
880 is empty, no token is printed.
884 .Li ${.newline}---${.MAKE:T}[${.MAKE.PID}]
885 would produce tokens like
886 .Ql ---make[1234] target ---
887 making it easier to track the degree of parallelism being achieved.
888 .It .MAKE.TARGET_LOCAL_VARIABLES
891 apparent variable assignments in dependency lines are
892 treated as normal sources.
894 The environment variable
896 may contain anything that
900 Anything specified on
902 command line is appended to the
904 variable which is then
905 entered into the environment for all programs which
909 The recursion depth of
911 The initial instance of
913 will be 0, and an incremented value is put into the environment
914 to be seen by the next generation.
915 This allows tests like:
916 .Li .if ${.MAKE.LEVEL} == 0
917 to protect things which should only be evaluated in the initial instance of
919 .It Va .MAKE.MAKEFILE_PREFERENCE
920 The ordered list of makefile names
927 .It Va .MAKE.MAKEFILES
928 The list of makefiles read by
930 which is useful for tracking dependencies.
931 Each makefile is recorded only once, regardless of the number of times read.
933 Processed after reading all makefiles.
934 Can affect the mode that
937 It can contain a number of keywords:
938 .Bl -hang -width missing-filemon=bf.
948 into "meta" mode, where meta files are created for each target
949 to capture the command run, the output generated and if
951 is available, the system calls which are of interest to
953 The captured output can be very useful when diagnosing errors.
954 .It Pa curdirOk= Ar bf
957 will not create .meta files in
959 This can be overridden by setting
961 to a value which represents True.
962 .It Pa missing-meta= Ar bf
965 is True, then a missing .meta file makes the target out-of-date.
966 .It Pa missing-filemon= Ar bf
969 is True, then missing filemon data makes the target out-of-date.
974 For debugging, it can be useful to include the environment
977 If in "meta" mode, print a clue about the target being built.
978 This is useful if the build is otherwise running silently.
979 The message printed the value of:
980 .Va .MAKE.META.PREFIX .
982 Some makefiles have commands which are simply not stable.
983 This keyword causes them to be ignored for
984 determining whether a target is out of date in "meta" mode.
990 is True, when a .meta file is created, mark the target
992 .It Pa randomize-targets
993 In both compat and parallel mode, do not make the targets in the usual order,
994 but instead randomize their order.
995 This mode can be used to detect undeclared dependencies between files.
997 .It Va .MAKE.META.BAILIWICK
998 In "meta" mode, provides a list of prefixes which
999 match the directories controlled by
1001 If a file that was generated outside of
1003 but within said bailiwick is missing,
1004 the current target is considered out-of-date.
1005 .It Va .MAKE.META.CMP_FILTER
1006 In "meta" mode, it can (very rarely!) be useful to filter command
1007 lines before comparison.
1008 This variable can be set to a set of modifiers that will be applied to
1009 each line of the old and new command that differ, if the filtered
1010 commands still differ, the target is considered out-of-date.
1011 .It Va .MAKE.META.CREATED
1012 In "meta" mode, this variable contains a list of all the meta files
1014 If not empty, it can be used to trigger processing of
1015 .Va .MAKE.META.FILES .
1016 .It Va .MAKE.META.FILES
1017 In "meta" mode, this variable contains a list of all the meta files
1018 used (updated or not).
1019 This list can be used to process the meta files to extract dependency
1021 .It Va .MAKE.META.IGNORE_PATHS
1022 Provides a list of path prefixes that should be ignored;
1023 because the contents are expected to change over time.
1024 The default list includes:
1025 .Sq Pa /dev /etc /proc /tmp /var/run /var/tmp
1026 .It Va .MAKE.META.IGNORE_PATTERNS
1027 Provides a list of patterns to match against pathnames.
1028 Ignore any that match.
1029 .It Va .MAKE.META.IGNORE_FILTER
1030 Provides a list of variable modifiers to apply to each pathname.
1031 Ignore if the expansion is an empty string.
1032 .It Va .MAKE.META.PREFIX
1033 Defines the message printed for each meta file updated in "meta verbose" mode.
1034 The default value is:
1035 .Dl Building ${.TARGET:H:tA}/${.TARGET:T}
1036 .It Va .MAKEOVERRIDES
1037 This variable is used to record the names of variables assigned to
1038 on the command line, so that they may be exported as part of
1040 This behavior can be disabled by assigning an empty value to
1041 .Sq Va .MAKEOVERRIDES
1043 Extra variables can be exported from a makefile
1044 by appending their names to
1045 .Sq Va .MAKEOVERRIDES .
1047 is re-exported whenever
1048 .Sq Va .MAKEOVERRIDES
1050 .It Va .MAKE.PATH_FILEMON
1055 support, this is set to the path of the device node.
1056 This allows makefiles to test for this support.
1061 The parent process-id of
1063 .It Va .MAKE.SAVE_DOLLARS
1064 value should be a boolean that controls whether
1066 are preserved when doing
1069 The default is false, for backwards compatibility.
1070 Set to true for compatability with other makes.
1075 per normal evaluation rules.
1080 The group-id running
1082 .It Va MAKE_PRINT_VAR_ON_ERROR
1085 stops due to an error, it sets
1086 .Sq Va .ERROR_TARGET
1087 to the name of the target that failed,
1089 to the commands of the failed target,
1090 and in "meta" mode, it also sets
1095 .Sq Va .ERROR_META_FILE
1096 to the path of the meta file (if any) describing the failed target.
1097 It then prints its name and the value of
1099 as well as the value of any variables named in
1100 .Sq Va MAKE_PRINT_VAR_ON_ERROR .
1102 This variable is simply assigned a newline character as its value.
1103 This allows expansions using the
1105 modifier to put a newline between
1106 iterations of the loop rather than a space.
1107 For example, the printing of
1108 .Sq Va MAKE_PRINT_VAR_ON_ERROR
1109 could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
1111 A path to the directory where the targets are built.
1112 Its value is determined by trying to
1114 to the following directories in order and using the first match:
1117 .Ev ${MAKEOBJDIRPREFIX}${.CURDIR}
1120 .Sq Ev MAKEOBJDIRPREFIX
1121 is set in the environment or on the command line.)
1127 is set in the environment or on the command line.)
1129 .Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE}
1131 .Ev ${.CURDIR} Ns Pa /obj
1133 .Pa /usr/obj/ Ns Ev ${.CURDIR}
1138 Variable expansion is performed on the value before it's used,
1139 so expressions such as
1140 .Dl ${.CURDIR:S,^/usr/src,/var/obj,}
1142 This is especially useful with
1146 may be modified in the makefile via the special target
1152 to the specified directory if it exists, and set
1156 to that directory before executing any targets.
1158 Except in the case of an explicit
1162 will check that the specified directory is writable and ignore it if not.
1163 This check can be skipped by setting the environment variable
1164 .Sq Ev MAKE_OBJDIR_CHECK_WRITABLE
1168 A path to the directory of the current
1172 The basename of the current
1177 are both set only while the
1180 If you want to retain their current values, assign them to a variable
1181 using assignment with expansion
1184 A variable that represents the list of directories that
1186 will search for files.
1187 The search list should be updated using the target
1189 rather than the variable.
1191 Alternate path to the current directory.
1195 to the canonical path given by
1197 However, if the environment variable
1199 is set and gives a path to the current directory, then
1206 This behavior is disabled if
1207 .Sq Ev MAKEOBJDIRPREFIX
1210 contains a variable transform.
1212 is set to the value of
1214 for all programs which
1218 The pathname of the shell used to run target scripts.
1221 The list of known suffixes.
1224 The list of targets explicitly specified on the command line, if any.
1228 lists of directories that
1230 will search for files.
1231 The variable is supported for compatibility with old make programs only,
1236 .Ss Variable modifiers
1237 Variable expansion may be modified to select or modify each word of the
1240 is white-space delimited sequence of characters).
1241 The general format of a variable expansion is as follows:
1243 .Dl ${variable[:modifier[:...]]}
1245 Each modifier begins with a colon,
1246 which may be escaped with a backslash
1249 A set of modifiers can be specified via a variable, as follows:
1251 .Dl modifier_variable=modifier[:...]
1252 .Dl ${variable:${modifier_variable}[:...]}
1254 In this case the first modifier in the modifier_variable does not
1255 start with a colon, since that must appear in the referencing
1257 If any of the modifiers in the modifier_variable contain a dollar sign
1259 these must be doubled to avoid early expansion.
1261 The supported modifiers are:
1264 Replaces each word in the variable with its suffix.
1266 Replaces each word in the variable with everything but the last component.
1267 .It Cm \&:M\| Ns Ar pattern
1268 Selects only those words that match
1270 The standard shell wildcard characters
1277 The wildcard characters may be escaped with a backslash
1279 As a consequence of the way values are split into words, matched,
1280 and then joined, a construct like
1282 will normalize the inter-word spacing, removing all leading and
1283 trailing space, and converting multiple consecutive spaces
1286 .It Cm \&:N\| Ns Ar pattern
1287 This is identical to
1289 but selects all words which do not match
1292 Orders every word in variable alphabetically.
1294 Orders every word in variable numerically.
1295 A number followed by one of
1300 is multiplied by the appropriate factor (1024 (k), 1048576 (M), or
1302 Both upper- and lower-case letters are accepted.
1304 Orders every word in variable in reverse alphabetical order.
1306 Orders every word in variable in reverse numerical order.
1308 Shuffles the words in variable.
1309 The results will be different each time you are referring to the
1310 modified variable; use the assignment with expansion
1312 to prevent such behavior.
1314 .Bd -literal -offset indent
1315 LIST= uno due tre quattro
1316 RANDOM_LIST= ${LIST:Ox}
1317 STATIC_RANDOM_LIST:= ${LIST:Ox}
1320 @echo "${RANDOM_LIST}"
1321 @echo "${RANDOM_LIST}"
1322 @echo "${STATIC_RANDOM_LIST}"
1323 @echo "${STATIC_RANDOM_LIST}"
1325 may produce output similar to:
1326 .Bd -literal -offset indent
1333 Quotes every shell meta-character in the variable, so that it can be passed
1334 safely to the shell.
1336 Quotes every shell meta-character in the variable, and also doubles
1338 characters so that it can be passed
1339 safely through recursive invocations of
1341 This is equivalent to:
1342 .Sq \&:S/\e\&$/&&/g:Q .
1344 Replaces each word in the variable with everything but its suffix.
1345 .It Cm \&:range Ns Oo = Ns Ar count Oc
1346 The value is an integer sequence representing the words of the original
1347 value, or the supplied
1349 .It Cm \&:gmtime Ns Oo = Ns Ar utc Oc
1350 The value is a format string for
1356 value is not provided or is 0, the current time is used.
1358 Computes a 32-bit hash of the value and encode it as hex digits.
1359 .It Cm \&:localtime Ns Oo = Ns Ar utc Oc
1360 The value is a format string for
1366 value is not provided or is 0, the current time is used.
1368 Attempts to convert variable to an absolute path using
1370 if that fails, the value is unchanged.
1372 Converts variable to lower-case letters.
1373 .It Cm \&:ts Ns Ar c
1374 Words in the variable are normally separated by a space on expansion.
1375 This modifier sets the separator to the character
1379 is omitted, then no separator is used.
1380 The common escapes (including octal numeric codes) work as expected.
1382 Converts variable to upper-case letters.
1384 Causes the value to be treated as a single word
1385 (possibly containing embedded white space).
1389 Causes the value to be treated as a sequence of
1390 words delimited by white space.
1394 .It Cm \&:S\| No \&/ Ar old_string\| No \&/ Ar new_string\| No \&/ Op Cm 1gW
1396 Modifies the first occurrence of
1398 in each word of the variable's value, replacing it with
1402 is appended to the last delimiter of the pattern, all occurrences
1403 in each word are replaced.
1406 is appended to the last delimiter of the pattern, only the first occurrence
1410 is appended to the last delimiter of the pattern,
1411 then the value is treated as a single word
1412 (possibly containing embedded white space).
1418 is anchored at the beginning of each word.
1421 ends with a dollar sign
1423 it is anchored at the end of each word.
1434 Any character may be used as a delimiter for the parts of the modifier
1436 The anchoring, ampersand and delimiter characters may be escaped with a
1440 Variable expansion occurs in the normal fashion inside both
1444 with the single exception that a backslash is used to prevent the expansion
1447 not a preceding dollar sign as is usual.
1449 .It Cm \&:C\| No \&/ Ar pattern\| No \&/ Ar replacement\| No \&/ Op Cm 1gW
1453 modifier is just like the
1455 modifier except that the old and new strings, instead of being
1456 simple strings, are an extended regular expression (see
1464 Normally, the first occurrence of the pattern
1466 in each word of the value is substituted with
1470 modifier causes the substitution to apply to at most one word; the
1472 modifier causes the substitution to apply to as many instances of the
1475 as occur in the word or words it is found in; the
1477 modifier causes the value to be treated as a single word
1478 (possibly containing embedded white space).
1486 are subjected to variable expansion before being parsed as
1487 regular expressions.
1489 Replaces each word in the variable with its last path component.
1491 Removes adjacent duplicate words (like
1494 .It Cm \&:\&?\| Ar true_string\| Cm \&: Ar false_string
1496 If the variable name (not its value), when parsed as a .if conditional
1497 expression, evaluates to true, return as its value the
1499 otherwise return the
1501 Since the variable name is used as the expression, \&:\&? must be the
1502 first modifier after the variable name itself - which will, of course,
1503 usually contain variable expansions.
1504 A common error is trying to use expressions like
1505 .Dl ${NUMBERS:M42:?match:no}
1506 which actually tests defined(NUMBERS),
1507 to determine if any words match "42" you need to use something like:
1508 .Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} .
1509 .It Cm :\| Ns Ar old_string\| Ns Cm = Ns Ar new_string
1512 style variable substitution.
1513 It must be the last modifier specified.
1518 do not contain the pattern matching character
1520 then it is assumed that they are
1521 anchored at the end of each word, so only suffixes or entire
1522 words may be replaced.
1531 contains the pattern matching character
1535 matches, then the result is the
1539 contains the pattern matching character
1541 then it is not treated specially and it is printed as a literal
1544 If there is more than one pattern matching character
1550 only the first instance is treated specially (as the pattern character);
1551 all subsequent instances are treated as regular characters.
1553 Variable expansion occurs in the normal fashion inside both
1557 with the single exception that a backslash is used to prevent the
1558 expansion of a dollar sign
1560 not a preceding dollar sign as is usual.
1562 .It Cm \&:@ Ar temp\| Cm @ Ar string\| Cm @
1564 This is the loop expansion mechanism from the OSF Development
1565 Environment (ODE) make.
1568 loops, expansion occurs at the time of reference.
1571 to each word in the variable and evaluates
1573 The ODE convention is that
1575 should start and end with a period.
1577 .Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
1579 However a single character variable is often more readable:
1580 .Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
1581 .It Cm \&:_ Ns Oo Cm = Ns Ar var Oc
1582 Saves the current variable value in
1586 for later reference.
1588 .Bd -literal -offset indent
1589 M_cmpv.units = 1 1000 1000000
1590 M_cmpv = S,., ,g:_:range:@i@+ $${_:[-$$i]} \&\\
1591 \\* $${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh
1593 .Dv .if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}}
1598 is used to save the result of the
1600 modifier which is later referenced using the index values from
1602 .It Cm \&:U\| Ns Ar newval
1603 If the variable is undefined,
1606 If the variable is defined, the existing value is returned.
1607 This is another ODE make feature.
1608 It is handy for setting per-target CFLAGS for instance:
1609 .Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
1610 If a value is only required if the variable is undefined, use:
1611 .Dl ${VAR:D:Unewval}
1612 .It Cm \&:D\| Ns Ar newval
1613 If the variable is defined,
1617 The name of the variable is the value.
1619 The path of the node which has the same name as the variable
1621 If no such node exists or its path is null, then the
1622 name of the variable is used.
1623 In order for this modifier to work, the name (node) must at least have
1624 appeared on the rhs of a dependency.
1626 .It Cm \&:\&! Ar cmd\| Cm \&!
1628 The output of running
1632 If the variable is non-empty it is run as a command and the output
1633 becomes the new value.
1634 .It Cm \&::= Ns Ar str
1635 The variable is assigned the value
1638 This modifier and its variations are useful in
1639 obscure situations such as wanting to set a variable when shell commands
1641 These assignment modifiers always expand to
1642 nothing, so if appearing in a rule line by themselves should be
1643 preceded with something to keep
1649 helps avoid false matches with the
1653 modifier and since substitution always occurs the
1655 form is vaguely appropriate.
1656 .It Cm \&::?= Ns Ar str
1659 but only if the variable does not already have a value.
1660 .It Cm \&::+= Ns Ar str
1664 .It Cm \&::!= Ns Ar cmd
1665 Assign the output of
1668 .It Cm \&:\&[ Ns Ar range Ns Cm \&]
1669 Selects one or more words from the value,
1670 or performs other operations related to the way in which the
1671 value is divided into words.
1673 Ordinarily, a value is treated as a sequence of words
1674 delimited by white space.
1675 Some modifiers suppress this behavior,
1676 causing a value to be treated as a single word
1677 (possibly containing embedded white space).
1678 An empty value, or a value that consists entirely of white-space,
1679 is treated as a single word.
1680 For the purposes of the
1682 modifier, the words are indexed both forwards using positive integers
1683 (where index 1 represents the first word),
1684 and backwards using negative integers
1685 (where index \-1 represents the last word).
1689 is subjected to variable expansion, and the expanded result is
1690 then interpreted as follows:
1691 .Bl -tag -width index
1694 Selects a single word from the value.
1696 .It Ar start Ns Cm \&.. Ns Ar end
1697 Selects all words from
1704 selects all words from the second word to the last word.
1709 then the words are output in reverse order.
1712 selects all the words from last to first.
1713 If the list is already ordered, then this effectively reverses
1714 the list, but it is more efficient to use
1717 .Sq Cm \&:O:[-1..1] .
1720 Causes subsequent modifiers to treat the value as a single word
1721 (possibly containing embedded white space).
1722 Analogous to the effect of
1731 Causes subsequent modifiers to treat the value as a sequence of words
1732 delimited by white space.
1733 Analogous to the effect of
1738 Returns the number of words in the value.
1741 .Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
1742 Makefile inclusion, conditional structures and for loops reminiscent
1743 of the C programming language are provided in
1745 All such structures are identified by a line beginning with a single
1749 Files are included with either
1750 .Cm \&.include \&< Ns Ar file Ns Cm \&>
1752 .Cm \&.include \&\*q Ns Ar file Ns Cm \&\*q .
1753 Variables between the angle brackets or double quotes are expanded
1754 to form the file name.
1755 If angle brackets are used, the included makefile is expected to be in
1756 the system makefile directory.
1757 If double quotes are used, the including makefile's directory and any
1758 directories specified using the
1760 option are searched before the system
1762 For compatibility with other versions of
1764 .Ql include file ...
1767 If the include statement is written as
1771 then errors locating and/or opening include files are ignored.
1773 If the include statement is written as
1775 not only are errors locating and/or opening include files ignored,
1776 but stale dependencies within the included file will be ignored
1778 .Va .MAKE.DEPENDFILE .
1780 Conditional expressions are also preceded by a single dot as the first
1781 character of a line.
1782 The possible conditionals are as follows:
1784 .It Ic .error Ar message
1785 The message is printed along with the name of the makefile and line number,
1788 will exit immediately.
1789 .It Ic .export Ar variable ...
1790 Export the specified global variable.
1791 If no variable list is provided, all globals are exported
1792 except for internal variables (those that start with
1794 This is not affected by the
1796 flag, so should be used with caution.
1797 For compatibility with other
1800 .Ql export variable=value
1803 Appending a variable name to
1805 is equivalent to exporting a variable.
1806 .It Ic .export-env Ar variable ...
1809 except that the variable is not appended to
1810 .Va .MAKE.EXPORTED .
1811 This allows exporting a value to the environment which is different from that
1815 .It Ic .export-literal Ar variable ...
1818 except that variables in the value are not expanded.
1819 .It Ic .info Ar message
1820 The message is printed along with the name of the makefile and line number.
1821 .It Ic .undef Ar variable ...
1822 Un-define the specified global variables.
1823 Only global variables can be un-defined.
1824 .It Ic .unexport Ar variable ...
1827 The specified global
1829 will be removed from
1830 .Va .MAKE.EXPORTED .
1831 If no variable list is provided, all globals are unexported,
1835 .It Ic .unexport-env
1836 Unexport all globals previously exported and
1837 clear the environment inherited from the parent.
1838 This operation will cause a memory leak of the original environment,
1839 so should be used sparingly.
1842 being 0, would make sense.
1843 Also note that any variables which originated in the parent environment
1844 should be explicitly preserved if desired.
1846 .Bd -literal -offset indent
1847 .Li .if ${.MAKE.LEVEL} == 0
1854 Would result in an environment containing only
1856 which is the minimal useful environment.
1859 will also be pushed into the new environment.
1860 .It Ic .warning Ar message
1861 The message prefixed by
1863 is printed along with the name of the makefile and line number.
1864 .It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ...
1865 Test the value of an expression.
1866 .It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1867 Test the value of a variable.
1868 .It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1869 Test the value of a variable.
1870 .It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1871 Test the target being built.
1872 .It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ...
1873 Test the target being built.
1875 Reverse the sense of the last conditional.
1876 .It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ...
1881 .It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1886 .It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1891 .It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1896 .It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1902 End the body of the conditional.
1907 may be any one of the following:
1908 .Bl -tag -width "Cm XX"
1914 of higher precedence than
1920 will only evaluate a conditional as far as is necessary to determine
1922 Parentheses may be used to change the order of evaluation.
1923 The boolean operator
1925 may be used to logically negate an entire
1927 It is of higher precedence than
1932 may be any of the following:
1933 .Bl -tag -width defined
1935 Takes a variable name as an argument and evaluates to true if the variable
1938 Takes a target name as an argument and evaluates to true if the target
1939 was specified as part of
1941 command line or was declared the default target (either implicitly or
1944 before the line containing the conditional.
1946 Takes a variable, with possible modifiers, and evaluates to true if
1947 the expansion of the variable would result in an empty string.
1949 Takes a file name as an argument and evaluates to true if the file exists.
1950 The file is searched for on the system search path (see
1953 Takes a target name as an argument and evaluates to true if the target
1956 Takes a target name as an argument and evaluates to true if the target
1957 has been defined and has commands associated with it.
1961 may also be an arithmetic or string comparison.
1962 Variable expansion is
1963 performed on both sides of the comparison, after which the numerical
1964 values are compared.
1965 A value is interpreted as hexadecimal if it is
1966 preceded by 0x, otherwise it is decimal; octal numbers are not supported.
1967 The standard C relational operators are all supported.
1969 variable expansion, either the left or right hand side of a
1973 operator is not a numerical value, then
1974 string comparison is performed between the expanded
1976 If no relational operator is given, it is assumed that the expanded
1977 variable is being compared against 0, or an empty string in the case
1978 of a string comparison.
1982 is evaluating one of these conditional expressions, and it encounters
1983 a (white-space separated) word it doesn't recognize, either the
1987 expression is applied to it, depending on the form of the conditional.
1995 expression is applied.
1996 Similarly, if the form is
2002 expression is applied.
2004 If the conditional evaluates to true the parsing of the makefile continues
2006 If it evaluates to false, the following lines are skipped.
2007 In both cases this continues until a
2013 For loops are typically used to apply a set of rules to a list of files.
2014 The syntax of a for loop is:
2016 .Bl -tag -compact -width Ds
2017 .It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression
2024 is evaluated, it is split into words.
2025 On each iteration of the loop, one word is taken and assigned to each
2029 are substituted into the
2031 inside the body of the for loop.
2032 The number of words must come out even; that is, if there are three
2033 iteration variables, the number of words provided must be a multiple
2036 Comments begin with a hash
2038 character, anywhere but in a shell
2039 command line, and continue to the end of an unescaped new line.
2040 .Sh SPECIAL SOURCES (ATTRIBUTES)
2041 .Bl -tag -width .IGNOREx
2043 Target is never out of date, but always execute commands anyway.
2045 Ignore any errors from the commands associated with this target, exactly
2046 as if they all were preceded by a dash
2048 .\" .It Ic .INVISIBLE
2053 Mark all sources of this target as being up-to-date.
2055 Execute the commands associated with this target even if the
2059 options were specified.
2060 Normally used to mark recursive
2063 Create a meta file for the target, even if it is flagged as
2068 Usage in conjunction with
2070 is the most likely case.
2071 In "meta" mode, the target is out-of-date if the meta file is missing.
2073 Do not create a meta file for the target.
2074 Meta files are also not created for
2081 Ignore differences in commands when deciding if target is out of date.
2082 This is useful if the command contains a value which always changes.
2083 If the number of commands change, though, the target will still be out of date.
2084 The same effect applies to any command line that uses the variable
2086 which can be used for that purpose even when not otherwise needed or desired:
2087 .Bd -literal -offset indent
2089 skip-compare-for-some:
2090 @echo this will be compared
2091 @echo this will not ${.OODATE:M.NOMETA_CMP}
2092 @echo this will also be compared
2097 pattern suppresses any expansion of the unwanted variable.
2099 Do not search for the target in the directories specified by
2104 selects the first target it encounters as the default target to be built
2105 if no target was specified.
2106 This source prevents this target from being selected.
2108 If a target is marked with this attribute and
2110 can't figure out how to create it, it will ignore this fact and assume
2111 the file isn't needed or already exists.
2114 correspond to an actual file; it is always considered to be out of date,
2115 and will not be created with the
2118 Suffix-transformation rules are not applied to
2124 is interrupted, it normally removes any partially made targets.
2125 This source prevents the target from being removed.
2130 Do not echo any of the commands associated with this target, exactly
2131 as if they all were preceded by an at sign
2134 Turn the target into
2137 When the target is used as a source for another target, the other target
2138 acquires the commands, sources, and attributes (except for
2142 If the target already has commands, the
2144 target's commands are appended
2151 target commands to the target.
2155 appears in a dependency line, the sources that precede it are
2156 made before the sources that succeed it in the line.
2157 Since the dependents of files are not made until the file itself
2158 could be made, this also stops the dependents being built unless they
2159 are needed for another branch of the dependency tree.
2172 the output is always
2178 The ordering imposed by
2180 is only relevant for parallel makes.
2183 Special targets may not be included with other targets, i.e. they must be
2184 the only target specified.
2185 .Bl -tag -width .BEGINx
2187 Any command lines attached to this target are executed before anything
2192 rule for any target (that was used only as a
2195 can't figure out any other way to create.
2196 Only the shell script is used.
2199 variable of a target that inherits
2202 to the target's own name.
2203 .It Ic .DELETE_ON_ERROR
2204 If this target is present in the makefile, it globally causes make to
2205 delete targets whose commands fail.
2206 (By default, only targets whose commands are interrupted during
2207 execution are deleted.
2208 This is the historical behavior.)
2209 This setting can be used to help prevent half-finished or malformed
2210 targets from being left around and corrupting future rebuilds.
2212 Any command lines attached to this target are executed after everything
2215 Any command lines attached to this target are executed when another target fails.
2218 variable is set to the target that failed.
2220 .Ic MAKE_PRINT_VAR_ON_ERROR .
2222 Mark each of the sources with the
2225 If no sources are specified, this is the equivalent of specifying the
2231 is interrupted, the commands for this target will be executed.
2233 If no target is specified when
2235 is invoked, this target will be built.
2237 This target provides a way to specify flags for
2239 when the makefile is used.
2240 The flags are as if typed to the shell, though the
2244 .\" XXX: NOT YET!!!!
2245 .\" .It Ic .NOTPARALLEL
2246 .\" The named targets are executed in non parallel mode.
2247 .\" If no targets are
2248 .\" specified, then all targets are executed in non parallel mode.
2252 attribute to any specified sources.
2254 Disable parallel mode.
2258 for compatibility with other pmake variants.
2260 The source is a new value for
2266 to it and update the value of
2269 In parallel mode, the named targets are made in sequence.
2270 This ordering does not add targets to the list of targets to be made.
2272 Since the dependents of a target do not get built until the target itself
2273 could be built, unless
2275 is built by another part of the dependency graph,
2276 the following is a dependency loop:
2282 .\" XXX: NOT YET!!!!
2283 .\" .It Ic .PARALLEL
2284 .\" The named targets are executed in parallel mode.
2285 .\" If no targets are
2286 .\" specified, then all targets are executed in parallel mode.
2288 The sources are directories which are to be searched for files not
2289 found in the current directory.
2290 If no sources are specified, any previously specified directories are
2292 If the source is the special
2294 target, then the current working
2295 directory is searched last.
2296 .It Ic .PATH. Ns Va suffix
2299 but applies only to files with a particular suffix.
2300 The suffix must have been previously declared with
2305 attribute to any specified sources.
2307 If this is the first non-comment line in the main makefile,
2314 is included if it exists,
2315 to provide POSIX-compatible default rules.
2322 will contribute to the default rules.
2326 attribute to any specified sources.
2327 If no sources are specified, the
2329 attribute is applied to every
2334 will use to execute commands.
2335 The sources are a set of
2338 .Bl -tag -width hasErrCtls
2340 This is the minimal specification, used to select one of the built-in
2347 Specifies the path to the shell.
2349 Indicates whether the shell supports exit on error.
2351 The command to turn on error checking.
2353 The command to disable error checking.
2355 The command to turn on echoing of commands executed.
2357 The command to turn off echoing of commands executed.
2359 The output to filter after issuing the
2362 It is typically identical to
2365 The flag to pass the shell to enable error checking.
2367 The flag to pass the shell to enable command echoing.
2369 The string literal to pass the shell that results in a single newline
2370 character when used outside of any quoting characters.
2374 \&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e
2375 check="set \-e" ignore="set +e" \e
2376 echo="set \-v" quiet="set +v" filter="set +v" \e
2377 echoFlag=v errFlag=e newline="'\en'"
2382 attribute to any specified sources.
2383 If no sources are specified, the
2385 attribute is applied to every
2386 command in the file.
2388 This target gets run when a dependency file contains stale entries, having
2390 set to the name of that dependency file.
2392 Each source specifies a suffix to
2394 If no sources are specified, any previously specified suffixes are deleted.
2395 It allows the creation of suffix-transformation rules.
2401 cc \-o ${.TARGET} \-c ${.IMPSRC}
2406 uses the following environment variables, if they exist:
2412 .Ev MAKEOBJDIRPREFIX ,
2418 .Ev MAKEOBJDIRPREFIX
2421 may only be set in the environment or on the command line to
2423 and not as makefile variables;
2424 see the description of
2428 .Bl -tag -width /usr/share/mk -compact
2430 list of dependencies
2432 list of dependencies
2434 list of dependencies
2438 system makefile directory
2441 The basic make syntax is compatible between different versions of make;
2442 however the special variables, variable modifiers and conditionals are not.
2444 An incomplete list of changes in older versions of
2447 The way that .for loop variables are substituted changed after
2449 so that they still appear to be variable expansions.
2450 In particular this stops them being treated as syntax, and removes some
2451 obscure problems using them in .if statements.
2453 The way that parallel makes are scheduled changed in
2455 so that .ORDER and .WAIT apply recursively to the dependent nodes.
2456 The algorithms used may change again in the future.
2457 .Ss Other make dialects
2458 Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not
2459 support most of the features of
2461 as described in this manual.
2463 .Bl -bullet -offset indent
2469 declarations and most functionality pertaining to parallelization.
2470 (GNU make supports parallelization but lacks these features needed to
2471 control it effectively.)
2473 Directives, including for loops and conditionals and most of the
2474 forms of include files.
2475 (GNU make has its own incompatible and less powerful syntax for
2478 All built-in variables that begin with a dot.
2480 Most of the special sources and targets that begin with a dot,
2481 with the notable exception of
2487 Variable modifiers, except for the
2489 string substitution, which does not portably support globbing with
2491 and historically only works on declared suffixes.
2495 variable even in its short form; most makes support this functionality
2496 but its name varies.
2499 Some features are somewhat more portable, such as assignment with
2506 functionality is based on an older feature
2508 found in GNU make and many versions of SVR4 make; however,
2509 historically its behavior is too ill-defined (and too buggy) to rely
2516 variables are more or less universally portable, as is the
2519 Basic use of suffix rules (for files only in the current directory,
2520 not trying to chain transformations together, etc.) is also reasonably
2526 is derived from NetBSD
2528 It uses autoconf to facilitate portability to other platforms.
2536 implementation is based on Adam De Boor's pmake program which was written
2537 for Sprite at Berkeley.
2538 It was designed to be a parallel distributed make running jobs on different
2539 machines using a daemon called
2542 Historically the target/dependency
2544 has been used to FoRCe rebuilding (since the target/dependency
2545 does not exist... unless someone creates an
2551 syntax is difficult to parse without actually acting on the data.
2552 For instance, finding the end of a variable's use should involve scanning
2553 each of the modifiers, using the correct terminator for each field.
2556 just counts {} and () in order to find the end of a variable expansion.
2558 There is no way of escaping a space character in a filename.