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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
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23 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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30 .\" from: @(#)make.1 8.4 (Berkeley) 3/19/94
37 .Nd maintain program dependencies
55 is a program designed to simplify the maintenance of other programs.
56 Its input is a list of specifications as to the files upon which programs
57 and other files depend.
60 makefile option is given,
66 in order to find the specifications.
69 exists, it is read (see
72 This manual page is intended as a reference document only.
73 For a more thorough description of
75 and makefiles, please refer to
76 .%T "PMake \- A Tutorial" .
79 will prepend the contents of the
81 environment variable to the command line arguments before parsing them.
83 The options are as follows:
86 Try to be backwards compatible by executing a single shell per command and
87 by executing the commands to make the sources of a dependency line in sequence.
91 before reading the makefiles or doing anything else.
94 options are specified, each is interpreted relative to the previous one:
95 .Fl C Pa / Fl C Pa etc
101 to be 1, in the global context.
103 Turn on debugging, and specify which portions of
105 are to print debugging information.
106 Unless the flags are preceded by
108 they are added to the
110 environment variable and will be processed by any child make processes.
111 By default, debugging information is printed to standard error,
112 but this can be changed using the
115 The debugging output is always unbuffered; in addition, if debugging
116 is enabled but debugging output is not directed to standard output,
117 then the standard output is line buffered.
119 is one or more of the following:
122 Print all possible debugging information;
123 equivalent to specifying all of the debugging flags.
125 Print debugging information about archive searching and caching.
127 Print debugging information about current working directory.
129 Print debugging information about conditional evaluation.
131 Print debugging information about directory searching and caching.
133 Print debugging information about failed commands and targets.
134 .It Ar F Ns Oo Sy \&+ Oc Ns Ar filename
135 Specify where debugging output is written.
136 This must be the last flag, because it consumes the remainder of
138 If the character immediately after the
142 then the file will be opened in append mode;
143 otherwise the file will be overwritten.
148 then debugging output will be written to the
149 standard output or standard error output file descriptors respectively
152 option has no effect).
153 Otherwise, the output will be written to the named file.
154 If the file name ends
158 is replaced by the pid.
160 Print debugging information about loop evaluation.
162 Print the input graph before making anything.
164 Print the input graph after making everything, or before exiting
167 Print the input graph before exiting on error.
169 Print debugging information about running multiple shells.
171 Print commands in Makefiles regardless of whether or not they are prefixed by
173 or other "quiet" flags.
174 Also known as "loud" behavior.
176 Print debugging information about "meta" mode decisions about targets.
178 Print debugging information about making targets, including modification
181 Don't delete the temporary command scripts created when running commands.
182 These temporary scripts are created in the directory
185 environment variable, or in
189 is unset or set to the empty string.
190 The temporary scripts are created by
192 and have names of the form
195 This can create many files in
201 Print debugging information about makefile parsing.
203 Print debugging information about suffix-transformation rules.
205 Print debugging information about target list maintenance.
209 option to print raw values of variables.
211 Print debugging information about variable assignment.
213 Run shell commands with
215 so the actual commands are printed as they are executed.
218 Specify that environment variables override macro assignments within
221 Specify a makefile to read instead of the default
227 standard input is read.
228 Multiple makefiles may be specified, and are read in the order specified.
229 .It Fl I Ar directory
230 Specify a directory in which to search for makefiles and included makefiles.
231 The system makefile directory (or directories, see the
233 option) is automatically included as part of this list.
235 Ignore non-zero exit of shell commands in the makefile.
236 Equivalent to specifying
238 before each command line in the makefile.
242 be specified by the user.
246 option is in use in a recursive build, this option is passed by a make
247 to child makes to allow all the make processes in the build to
248 cooperate to avoid overloading the system.
250 Specify the maximum number of jobs that
252 may have running at any one time.
253 The value is saved in
255 Turns compatibility mode off, unless the
257 flag is also specified.
258 When compatibility mode is off, all commands associated with a
259 target are executed in a single shell invocation as opposed to the
260 traditional one shell invocation per line.
261 This can break traditional scripts which change directories on each
262 command invocation and then expect to start with a fresh environment
264 It is more efficient to correct the scripts rather than turn backwards
267 Continue processing after errors are encountered, but only on those targets
268 that do not depend on the target whose creation caused the error.
269 .It Fl m Ar directory
270 Specify a directory in which to search for sys.mk and makefiles included
272 .Ao Ar file Ac Ns -style
276 option can be used multiple times to form a search path.
277 This path will override the default system include path: /usr/share/mk.
278 Furthermore the system include path will be appended to the search path used
280 .Qo Ar file Qc Ns -style
281 include statements (see the
285 If a file or directory name in the
289 environment variable) starts with the string
293 will search for the specified file or directory named in the remaining part
294 of the argument string.
295 The search starts with the current directory of
296 the Makefile and then works upward towards the root of the filesystem.
297 If the search is successful, then the resulting directory replaces the
302 If used, this feature allows
304 to easily search in the current source tree for customized sys.mk files
309 Display the commands that would have been executed, but do not
310 actually execute them unless the target depends on the .MAKE special
313 Display the commands which would have been executed, but do not
314 actually execute any of them; useful for debugging top-level makefiles
315 without descending into subdirectories.
317 Do not execute any commands, but exit 0 if the specified targets are
318 up-to-date and 1, otherwise.
320 Do not use the built-in rules specified in the system makefile.
322 Do not echo any commands as they are executed.
323 Equivalent to specifying
325 before each command line in the makefile.
326 .It Fl T Ar tracefile
330 append a trace record to
332 for each job started and completed.
334 Rather than re-building a target as specified in the makefile, create it
335 or update its modification time to make it appear up-to-date.
341 in the global context.
342 Do not build any targets.
343 Multiple instances of this option may be specified;
344 the variables will be printed one per line,
345 with a blank line for each null or undefined variable.
350 then the value will be expanded before printing.
352 Treat any warnings during makefile parsing as errors.
354 Print entering and leaving directory messages, pre and post processing.
356 Don't export variables passed on the command line to the environment
358 Variables passed on the command line are still exported
361 environment variable.
362 This option may be useful on systems which have a small limit on the
363 size of command arguments.
364 .It Ar variable=value
365 Set the value of the variable
369 Normally, all values passed on the command line are also exported to
370 sub-makes in the environment.
373 flag disables this behavior.
374 Variable assignments should follow options for POSIX compatibility
375 but no ordering is enforced.
378 There are seven different types of lines in a makefile: file dependency
379 specifications, shell commands, variable assignments, include statements,
380 conditional directives, for loops, and comments.
382 In general, lines may be continued from one line to the next by ending
383 them with a backslash
385 The trailing newline character and initial whitespace on the following
386 line are compressed into a single space.
387 .Sh FILE DEPENDENCY SPECIFICATIONS
388 Dependency lines consist of one or more targets, an operator, and zero
390 This creates a relationship where the targets
393 and are usually created from them.
394 The exact relationship between the target and the source is determined
395 by the operator that separates them.
396 The three operators are as follows:
399 A target is considered out-of-date if its modification time is less than
400 those of any of its sources.
401 Sources for a target accumulate over dependency lines when this operator
403 The target is removed if
407 Targets are always re-created, but not until all sources have been
408 examined and re-created as necessary.
409 Sources for a target accumulate over dependency lines when this operator
411 The target is removed if
415 If no sources are specified, the target is always re-created.
416 Otherwise, a target is considered out-of-date if any of its sources has
417 been modified more recently than the target.
418 Sources for a target do not accumulate over dependency lines when this
420 The target will not be removed if
425 Targets and sources may contain the shell wildcard values
436 may only be used as part of the final
437 component of the target or source, and must be used to describe existing
441 need not necessarily be used to describe existing files.
442 Expansion is in directory order, not alphabetically as done in the shell.
444 Each target may have associated with it one or more lines of shell
446 used to create the target.
447 Each of the lines in this script
449 be preceded by a tab.
450 (For historical reasons, spaces are not accepted.)
451 While targets can appear in many dependency lines if desired, by
452 default only one of these rules may be followed by a creation
456 operator is used, however, all rules may include scripts and the
457 scripts are executed in the order found.
459 Each line is treated as a separate shell command, unless the end of
460 line is escaped with a backslash
462 in which case that line and the next are combined.
463 .\" The escaped newline is retained and passed to the shell, which
464 .\" normally ignores it.
465 .\" However, the tab at the beginning of the following line is removed.
466 If the first characters of the command are any combination of
471 the command is treated specially.
474 causes the command not to be echoed before it is executed.
477 causes the command to be executed even when
480 This is similar to the effect of the .MAKE special source,
481 except that the effect can be limited to a single line of a script.
484 in compatibility mode
485 causes any non-zero exit status of the command line to be ignored.
489 is run in jobs mode with
491 the entire script for the target is fed to a
492 single instance of the shell.
493 In compatibility (non-jobs) mode, each command is run in a separate process.
494 If the command contains any shell meta characters
495 .Pq Ql #=|^(){};&<>*?[]:$`\e\en
496 it will be passed to the shell; otherwise
498 will attempt direct execution.
499 If a line starts with
501 and the shell has ErrCtl enabled then failure of the command line
502 will be ignored as in compatibility mode.
505 affects the entire job;
506 the script will stop at the first command line that fails,
507 but the target will not be deemed to have failed.
509 Makefiles should be written so that the mode of
511 operation does not change their behavior.
512 For example, any command which needs to use
516 without potentially changing the directory for subsequent commands
517 should be put in parentheses so it executes in a subshell.
518 To force the use of one shell, escape the line breaks so as to make
519 the whole script one command.
521 .Bd -literal -offset indent
522 avoid-chdir-side-effects:
523 @echo Building $@ in `pwd`
524 @(cd ${.CURDIR} && ${MAKE} $@)
527 ensure-one-shell-regardless-of-mode:
528 @echo Building $@ in `pwd`; \e
529 (cd ${.CURDIR} && ${MAKE} $@); \e
539 before executing any targets, each child process
540 starts with that as its current working directory.
541 .Sh VARIABLE ASSIGNMENTS
542 Variables in make are much like variables in the shell, and, by tradition,
543 consist of all upper-case letters.
544 .Ss Variable assignment modifiers
545 The five operators that can be used to assign values to variables are as
549 Assign the value to the variable.
550 Any previous value is overridden.
552 Append the value to the current value of the variable.
554 Assign the value to the variable if it is not already defined.
556 Assign with expansion, i.e. expand the value before assigning it
558 Normally, expansion is not done until the variable is referenced.
560 References to undefined variables are
563 This can cause problems when variable modifiers are used.
565 Expand the value and pass it to the shell for execution and assign
566 the result to the variable.
567 Any newlines in the result are replaced with spaces.
570 Any white-space before the assigned
572 is removed; if the value is being appended, a single space is inserted
573 between the previous contents of the variable and the appended value.
575 Variables are expanded by surrounding the variable name with either
580 and preceding it with
583 If the variable name contains only a single letter, the surrounding
584 braces or parentheses are not required.
585 This shorter form is not recommended.
587 If the variable name contains a dollar, then the name itself is expanded first.
588 This allows almost arbitrary variable names, however names containing dollar,
589 braces, parenthesis, or whitespace are really best avoided!
591 If the result of expanding a variable contains a dollar sign
593 the string is expanded again.
595 Variable substitution occurs at three distinct times, depending on where
596 the variable is being used.
599 Variables in dependency lines are expanded as the line is read.
601 Variables in shell commands are expanded when the shell command is
605 loop index variables are expanded on each loop iteration.
606 Note that other variables are not expanded inside loops so
607 the following example code:
608 .Bd -literal -offset indent
622 .Bd -literal -offset indent
627 Because while ${a} contains
629 after the loop is executed, ${b}
634 since after the loop completes ${j} contains
638 The four different classes of variables (in order of increasing precedence)
641 .It Environment variables
642 Variables defined as part of
646 Variables defined in the makefile or in included makefiles.
647 .It Command line variables
648 Variables defined as part of the command line.
650 Variables that are defined specific to a certain target.
653 Local variables are all built in and their values vary magically from
655 It is not currently possible to define new local variables.
656 The seven local variables are as follows:
657 .Bl -tag -width ".ARCHIVE" -offset indent
659 The list of all sources for this target; also known as
662 The name of the archive file; also known as
665 In suffix-transformation rules, the name/path of the source from which the
666 target is to be transformed (the
668 source); also known as
670 It is not defined in explicit rules.
672 The name of the archive member; also known as
675 The list of sources for this target that were deemed out-of-date; also
679 The file prefix of the target, containing only the file portion, no suffix
680 or preceding directory components; also known as
682 The suffix must be one of the known suffixes declared with
684 or it will not be recognized.
686 The name of the target; also known as
699 are permitted for backward
700 compatibility with historical makefiles and legacy POSIX make and are
703 Variants of these variables with the punctuation followed immediately by
709 are legacy forms equivalent to using the
714 These forms are accepted for compatibility with
716 makefiles and POSIX but are not recommended.
718 Four of the local variables may be used in sources on dependency lines
719 because they expand to the proper value for each target on the line.
726 .Ss Additional built-in variables
729 sets or knows about the following variables:
730 .Bl -tag -width .MAKEOVERRIDES
736 expands to a single dollar
739 The list of all targets encountered in the Makefile.
741 Makefile parsing, lists only those targets encountered thus far.
743 A path to the directory where
746 Refer to the description of
749 .It Va .INCLUDEDFROMDIR
750 The directory of the file this Makefile was included from.
751 .It Va .INCLUDEDFROMFILE
752 The filename of the file this Makefile was included from.
763 The preferred variable to use is the environment variable
765 because it is more compatible with other versions of
767 and cannot be confused with the special target with the same name.
768 .It Va .MAKE.DEPENDFILE
769 Names the makefile (default
771 from which generated dependencies are read.
772 .It Va .MAKE.EXPAND_VARIABLES
773 A boolean that controls the default behavior of the
776 .It Va .MAKE.EXPORTED
777 The list of variables exported by
783 .It Va .MAKE.JOB.PREFIX
788 then output for each target is prefixed with a token
790 the first part of which can be controlled via
791 .Va .MAKE.JOB.PREFIX .
794 is empty, no token is printed.
797 .Li .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
798 would produce tokens like
799 .Ql ---make[1234] target ---
800 making it easier to track the degree of parallelism being achieved.
802 The environment variable
804 may contain anything that
808 Anything specified on
810 command line is appended to the
812 variable which is then
813 entered into the environment for all programs which
817 The recursion depth of
819 The initial instance of
821 will be 0, and an incremented value is put into the environment
822 to be seen by the next generation.
823 This allows tests like:
824 .Li .if ${.MAKE.LEVEL} == 0
825 to protect things which should only be evaluated in the initial instance of
827 .It Va .MAKE.MAKEFILE_PREFERENCE
828 The ordered list of makefile names
835 .It Va .MAKE.MAKEFILES
836 The list of makefiles read by
838 which is useful for tracking dependencies.
839 Each makefile is recorded only once, regardless of the number of times read.
841 Processed after reading all makefiles.
842 Can affect the mode that
845 It can contain a number of keywords:
846 .Bl -hang -width ignore-cmd
856 into "meta" mode, where meta files are created for each target
857 to capture the command run, the output generated and if
859 is available, the system calls which are of interest to
861 The captured output can be very useful when diagnosing errors.
862 .It Pa curdirOk= Ar bf
865 will not create .meta files in
867 This can be overridden by setting
869 to a value which represents True.
871 For debugging, it can be useful to inlcude the environment
874 If in "meta" mode, print a clue about the target being built.
875 This is useful if the build is otherwise running silently.
876 The message printed the value of:
877 .Va .MAKE.META.PREFIX .
879 Some makefiles have commands which are simply not stable.
880 This keyword causes them to be ignored for
881 determining whether a target is out of date in "meta" mode.
887 is True, when a .meta file is created, mark the target
890 .It Va .MAKE.META.BAILIWICK
891 In "meta" mode, provides a list of prefixes which
892 match the directories controlled by
894 If a file that was generated outside of
896 but within said bailiwick is missing,
897 the current target is considered out-of-date.
898 .It Va .MAKE.META.CREATED
899 In "meta" mode, this variable contains a list of all the meta files
901 If not empty, it can be used to trigger processing of
902 .Va .MAKE.META.FILES .
903 .It Va .MAKE.META.FILES
904 In "meta" mode, this variable contains a list of all the meta files
905 used (updated or not).
906 This list can be used to process the meta files to extract dependency
908 .It Va .MAKE.META.IGNORE_PATHS
909 Provides a list of path prefixes that should be ignored;
910 because the contents are expected to change over time.
911 The default list includes:
912 .Ql Pa /dev /etc /proc /tmp /var/run /var/tmp
913 .It Va .MAKE.META.PREFIX
914 Defines the message printed for each meta file updated in "meta verbose" mode.
915 The default value is:
916 .Dl Building ${.TARGET:H:tA}/${.TARGET:T}
917 .It Va .MAKEOVERRIDES
918 This variable is used to record the names of variables assigned to
919 on the command line, so that they may be exported as part of
921 This behaviour can be disabled by assigning an empty value to
922 .Ql Va .MAKEOVERRIDES
924 Extra variables can be exported from a makefile
925 by appending their names to
926 .Ql Va .MAKEOVERRIDES .
928 is re-exported whenever
929 .Ql Va .MAKEOVERRIDES
931 .It Va .MAKE.PATH_FILEMON
936 support, this is set to the path of the device node.
937 This allows makefiles to test for this support.
942 The parent process-id of
944 .It Va MAKE_PRINT_VAR_ON_ERROR
947 stops due to an error, it prints its name and the value of
949 as well as the value of any variables named in
950 .Ql Va MAKE_PRINT_VAR_ON_ERROR .
952 This variable is simply assigned a newline character as its value.
953 This allows expansions using the
955 modifier to put a newline between
956 iterations of the loop rather than a space.
957 For example, the printing of
958 .Ql Va MAKE_PRINT_VAR_ON_ERROR
959 could be done as ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
961 A path to the directory where the targets are built.
962 Its value is determined by trying to
964 to the following directories in order and using the first match:
967 .Ev ${MAKEOBJDIRPREFIX}${.CURDIR}
970 .Ql Ev MAKEOBJDIRPREFIX
971 is set in the environment or on the command line.)
977 is set in the environment or on the command line.)
979 .Ev ${.CURDIR} Ns Pa /obj. Ns Ev ${MACHINE}
981 .Ev ${.CURDIR} Ns Pa /obj
983 .Pa /usr/obj/ Ns Ev ${.CURDIR}
988 Variable expansion is performed on the value before it's used,
989 so expressions such as
990 .Dl ${.CURDIR:S,^/usr/src,/var/obj,}
992 This is especially useful with
996 may be modified in the makefile as a global variable.
1005 to that directory before executing any targets.
1008 A path to the directory of the current
1012 The basename of the current
1017 are both set only while the
1020 If you want to retain their current values, assign them to a variable
1021 using assignment with expansion:
1024 A variable that represents the list of directories that
1026 will search for files.
1027 The search list should be updated using the target
1029 rather than the variable.
1031 Alternate path to the current directory.
1035 to the canonical path given by
1037 However, if the environment variable
1039 is set and gives a path to the current directory, then
1046 This behaviour is disabled if
1047 .Ql Ev MAKEOBJDIRPREFIX
1050 contains a variable transform.
1052 is set to the value of
1054 for all programs which
1058 The list of targets explicitly specified on the command line, if any.
1062 lists of directories that
1064 will search for files.
1065 The variable is supported for compatibility with old make programs only,
1070 .Ss Variable modifiers
1071 Variable expansion may be modified to select or modify each word of the
1074 is white-space delimited sequence of characters).
1075 The general format of a variable expansion is as follows:
1077 .Dl ${variable[:modifier[:...]]}
1079 Each modifier begins with a colon,
1080 which may be escaped with a backslash
1083 A set of modifiers can be specified via a variable, as follows:
1085 .Dl modifier_variable=modifier[:...]
1086 .Dl ${variable:${modifier_variable}[:...]}
1088 In this case the first modifier in the modifier_variable does not
1089 start with a colon, since that must appear in the referencing
1091 If any of the modifiers in the modifier_variable contain a dollar sign
1093 these must be doubled to avoid early expansion.
1095 The supported modifiers are:
1098 Replaces each word in the variable with its suffix.
1100 Replaces each word in the variable with everything but the last component.
1101 .It Cm \&:M Ns Ar pattern
1102 Select only those words that match
1104 The standard shell wildcard characters
1111 The wildcard characters may be escaped with a backslash
1113 As a consequence of the way values are split into words, matched,
1114 and then joined, a construct like
1116 will normalise the inter-word spacing, removing all leading and
1117 trailing space, and converting multiple consecutive spaces
1120 .It Cm \&:N Ns Ar pattern
1121 This is identical to
1123 but selects all words which do not match
1126 Order every word in variable alphabetically.
1128 reverse order use the
1130 combination of modifiers.
1132 Randomize words in variable.
1133 The results will be different each time you are referring to the
1134 modified variable; use the assignment with expansion
1136 to prevent such behaviour.
1138 .Bd -literal -offset indent
1139 LIST= uno due tre quattro
1140 RANDOM_LIST= ${LIST:Ox}
1141 STATIC_RANDOM_LIST:= ${LIST:Ox}
1144 @echo "${RANDOM_LIST}"
1145 @echo "${RANDOM_LIST}"
1146 @echo "${STATIC_RANDOM_LIST}"
1147 @echo "${STATIC_RANDOM_LIST}"
1149 may produce output similar to:
1150 .Bd -literal -offset indent
1157 Quotes every shell meta-character in the variable, so that it can be passed
1158 safely through recursive invocations of
1161 Replaces each word in the variable with everything but its suffix.
1163 The value is a format string for
1168 Compute a 32bit hash of the value and encode it as hex digits.
1170 The value is a format string for
1175 Attempt to convert variable to an absolute path using
1177 if that fails, the value is unchanged.
1179 Converts variable to lower-case letters.
1180 .It Cm \&:ts Ns Ar c
1181 Words in the variable are normally separated by a space on expansion.
1182 This modifier sets the separator to the character
1186 is omitted, then no separator is used.
1187 The common escapes (including octal numeric codes), work as expected.
1189 Converts variable to upper-case letters.
1191 Causes the value to be treated as a single word
1192 (possibly containing embedded white space).
1196 Causes the value to be treated as a sequence of
1197 words delimited by white space.
1201 .It Cm \&:S No \&/ Ar old_string No \&/ Ar new_string No \&/ Op Cm 1gW
1203 Modify the first occurrence of
1205 in the variable's value, replacing it with
1209 is appended to the last slash of the pattern, all occurrences
1210 in each word are replaced.
1213 is appended to the last slash of the pattern, only the first word
1217 is appended to the last slash of the pattern,
1218 then the value is treated as a single word
1219 (possibly containing embedded white space).
1225 is anchored at the beginning of each word.
1228 ends with a dollar sign
1230 it is anchored at the end of each word.
1241 Any character may be used as a delimiter for the parts of the modifier
1243 The anchoring, ampersand and delimiter characters may be escaped with a
1247 Variable expansion occurs in the normal fashion inside both
1251 with the single exception that a backslash is used to prevent the expansion
1254 not a preceding dollar sign as is usual.
1256 .It Cm \&:C No \&/ Ar pattern No \&/ Ar replacement No \&/ Op Cm 1gW
1260 modifier is just like the
1262 modifier except that the old and new strings, instead of being
1263 simple strings, are an extended regular expression (see
1271 Normally, the first occurrence of the pattern
1273 in each word of the value is substituted with
1277 modifier causes the substitution to apply to at most one word; the
1279 modifier causes the substitution to apply to as many instances of the
1282 as occur in the word or words it is found in; the
1284 modifier causes the value to be treated as a single word
1285 (possibly containing embedded white space).
1290 are orthogonal; the former specifies whether multiple words are
1291 potentially affected, the latter whether multiple substitutions can
1292 potentially occur within each affected word.
1300 are subjected to variable expansion before being parsed as
1301 regular expressions.
1303 Replaces each word in the variable with its last component.
1305 Remove adjacent duplicate words (like
1308 .It Cm \&:\&? Ar true_string Cm \&: Ar false_string
1310 If the variable name (not its value), when parsed as a .if conditional
1311 expression, evaluates to true, return as its value the
1313 otherwise return the
1315 Since the variable name is used as the expression, \&:\&? must be the
1316 first modifier after the variable name itself - which will, of course,
1317 usually contain variable expansions.
1318 A common error is trying to use expressions like
1319 .Dl ${NUMBERS:M42:?match:no}
1320 which actually tests defined(NUMBERS),
1321 to determine is any words match "42" you need to use something like:
1322 .Dl ${"${NUMBERS:M42}" != \&"\&":?match:no} .
1323 .It Ar :old_string=new_string
1326 style variable substitution.
1327 It must be the last modifier specified.
1332 do not contain the pattern matching character
1334 then it is assumed that they are
1335 anchored at the end of each word, so only suffixes or entire
1336 words may be replaced.
1344 Variable expansion occurs in the normal fashion inside both
1348 with the single exception that a backslash is used to prevent the
1349 expansion of a dollar sign
1351 not a preceding dollar sign as is usual.
1353 .It Cm \&:@ Ar temp Cm @ Ar string Cm @
1355 This is the loop expansion mechanism from the OSF Development
1356 Environment (ODE) make.
1359 loops expansion occurs at the time of
1363 to each word in the variable and evaluate
1365 The ODE convention is that
1367 should start and end with a period.
1369 .Dl ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
1371 However a single character variable is often more readable:
1372 .Dl ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
1373 .It Cm \&:U Ns Ar newval
1374 If the variable is undefined
1377 If the variable is defined, the existing value is returned.
1378 This is another ODE make feature.
1379 It is handy for setting per-target CFLAGS for instance:
1380 .Dl ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
1381 If a value is only required if the variable is undefined, use:
1382 .Dl ${VAR:D:Unewval}
1383 .It Cm \&:D Ns Ar newval
1384 If the variable is defined
1388 The name of the variable is the value.
1390 The path of the node which has the same name as the variable
1392 If no such node exists or its path is null, then the
1393 name of the variable is used.
1394 In order for this modifier to work, the name (node) must at least have
1395 appeared on the rhs of a dependency.
1397 .It Cm \&:\&! Ar cmd Cm \&!
1399 The output of running
1403 If the variable is non-empty it is run as a command and the output
1404 becomes the new value.
1405 .It Cm \&::= Ns Ar str
1406 The variable is assigned the value
1409 This modifier and its variations are useful in
1410 obscure situations such as wanting to set a variable when shell commands
1412 These assignment modifiers always expand to
1413 nothing, so if appearing in a rule line by themselves should be
1414 preceded with something to keep
1420 helps avoid false matches with the
1424 modifier and since substitution always occurs the
1426 form is vaguely appropriate.
1427 .It Cm \&::?= Ns Ar str
1430 but only if the variable does not already have a value.
1431 .It Cm \&::+= Ns Ar str
1435 .It Cm \&::!= Ns Ar cmd
1436 Assign the output of
1439 .It Cm \&:\&[ Ns Ar range Ns Cm \&]
1440 Selects one or more words from the value,
1441 or performs other operations related to the way in which the
1442 value is divided into words.
1444 Ordinarily, a value is treated as a sequence of words
1445 delimited by white space.
1446 Some modifiers suppress this behaviour,
1447 causing a value to be treated as a single word
1448 (possibly containing embedded white space).
1449 An empty value, or a value that consists entirely of white-space,
1450 is treated as a single word.
1451 For the purposes of the
1453 modifier, the words are indexed both forwards using positive integers
1454 (where index 1 represents the first word),
1455 and backwards using negative integers
1456 (where index \-1 represents the last word).
1460 is subjected to variable expansion, and the expanded result is
1461 then interpreted as follows:
1462 .Bl -tag -width index
1465 Selects a single word from the value.
1467 .It Ar start Ns Cm \&.. Ns Ar end
1468 Selects all words from
1475 selects all words from the second word to the last word.
1480 then the words are output in reverse order.
1483 selects all the words from last to first.
1486 Causes subsequent modifiers to treat the value as a single word
1487 (possibly containing embedded white space).
1488 Analogous to the effect of
1497 Causes subsequent modifiers to treat the value as a sequence of words
1498 delimited by white space.
1499 Analogous to the effect of
1504 Returns the number of words in the value.
1507 .Sh INCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS
1508 Makefile inclusion, conditional structures and for loops reminiscent
1509 of the C programming language are provided in
1511 All such structures are identified by a line beginning with a single
1515 Files are included with either
1516 .Cm \&.include Aq Ar file
1518 .Cm \&.include Pf \*q Ar file Ns \*q .
1519 Variables between the angle brackets or double quotes are expanded
1520 to form the file name.
1521 If angle brackets are used, the included makefile is expected to be in
1522 the system makefile directory.
1523 If double quotes are used, the including makefile's directory and any
1524 directories specified using the
1526 option are searched before the system
1528 For compatibility with other versions of
1530 .Ql include file ...
1532 If the include statement is written as
1536 then errors locating and/or opening include files are ignored.
1538 Conditional expressions are also preceded by a single dot as the first
1539 character of a line.
1540 The possible conditionals are as follows:
1542 .It Ic .error Ar message
1543 The message is printed along with the name of the makefile and line number,
1547 .It Ic .export Ar variable ...
1548 Export the specified global variable.
1549 If no variable list is provided, all globals are exported
1550 except for internal variables (those that start with
1552 This is not affected by the
1554 flag, so should be used with caution.
1555 For compatibility with other
1558 .Ql export variable=value
1561 Appending a variable name to
1563 is equivalent to exporting a variable.
1564 .It Ic .export-env Ar variable ...
1567 except that the variable is not appended to
1568 .Va .MAKE.EXPORTED .
1569 This allows exporting a value to the environment which is different from that
1573 .It Ic .info Ar message
1574 The message is printed along with the name of the makefile and line number.
1575 .It Ic .undef Ar variable
1576 Un-define the specified global variable.
1577 Only global variables may be un-defined.
1578 .It Ic .unexport Ar variable ...
1581 The specified global
1583 will be removed from
1584 .Va .MAKE.EXPORTED .
1585 If no variable list is provided, all globals are unexported,
1589 .It Ic .unexport-env
1590 Unexport all globals previously exported and
1591 clear the environment inherited from the parent.
1592 This operation will cause a memory leak of the original environment,
1593 so should be used sparingly.
1596 being 0, would make sense.
1597 Also note that any variables which originated in the parent environment
1598 should be explicitly preserved if desired.
1600 .Bd -literal -offset indent
1601 .Li .if ${.MAKE.LEVEL} == 0
1608 Would result in an environment containing only
1610 which is the minimal useful environment.
1613 will also be pushed into the new environment.
1614 .It Ic .warning Ar message
1615 The message prefixed by
1617 is printed along with the name of the makefile and line number.
1618 .It Ic \&.if Oo \&! Oc Ns Ar expression Op Ar operator expression ...
1619 Test the value of an expression.
1620 .It Ic .ifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1621 Test the value of a variable.
1622 .It Ic .ifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1623 Test the value of a variable.
1624 .It Ic .ifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1625 Test the target being built.
1626 .It Ic .ifnmake Oo \&! Ns Oc Ar target Op Ar operator target ...
1627 Test the target being built.
1629 Reverse the sense of the last conditional.
1630 .It Ic .elif Oo \&! Ns Oc Ar expression Op Ar operator expression ...
1635 .It Ic .elifdef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1640 .It Ic .elifndef Oo \&! Oc Ns Ar variable Op Ar operator variable ...
1645 .It Ic .elifmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1650 .It Ic .elifnmake Oo \&! Oc Ns Ar target Op Ar operator target ...
1656 End the body of the conditional.
1661 may be any one of the following:
1662 .Bl -tag -width "Cm XX"
1665 .It Cm \&\*[Am]\*[Am]
1668 of higher precedence than
1674 will only evaluate a conditional as far as is necessary to determine
1676 Parentheses may be used to change the order of evaluation.
1677 The boolean operator
1679 may be used to logically negate an entire
1681 It is of higher precedence than
1682 .Ql Ic \&\*[Am]\*[Am] .
1686 may be any of the following:
1687 .Bl -tag -width defined
1689 Takes a variable name as an argument and evaluates to true if the variable
1692 Takes a target name as an argument and evaluates to true if the target
1693 was specified as part of
1695 command line or was declared the default target (either implicitly or
1698 before the line containing the conditional.
1700 Takes a variable, with possible modifiers, and evaluates to true if
1701 the expansion of the variable would result in an empty string.
1703 Takes a file name as an argument and evaluates to true if the file exists.
1704 The file is searched for on the system search path (see
1707 Takes a target name as an argument and evaluates to true if the target
1710 Takes a target name as an argument and evaluates to true if the target
1711 has been defined and has commands associated with it.
1715 may also be an arithmetic or string comparison.
1716 Variable expansion is
1717 performed on both sides of the comparison, after which the integral
1718 values are compared.
1719 A value is interpreted as hexadecimal if it is
1720 preceded by 0x, otherwise it is decimal; octal numbers are not supported.
1721 The standard C relational operators are all supported.
1723 variable expansion, either the left or right hand side of a
1727 operator is not an integral value, then
1728 string comparison is performed between the expanded
1730 If no relational operator is given, it is assumed that the expanded
1731 variable is being compared against 0 or an empty string in the case
1732 of a string comparison.
1736 is evaluating one of these conditional expressions, and it encounters
1737 a (white-space separated) word it doesn't recognize, either the
1741 expression is applied to it, depending on the form of the conditional.
1749 expression is applied.
1750 Similarly, if the form is
1753 .Ql Ic .ifnmake , the
1755 expression is applied.
1757 If the conditional evaluates to true the parsing of the makefile continues
1759 If it evaluates to false, the following lines are skipped.
1760 In both cases this continues until a
1766 For loops are typically used to apply a set of rules to a list of files.
1767 The syntax of a for loop is:
1769 .Bl -tag -compact -width Ds
1770 .It Ic \&.for Ar variable Oo Ar variable ... Oc Ic in Ar expression
1777 is evaluated, it is split into words.
1778 On each iteration of the loop, one word is taken and assigned to each
1782 are substituted into the
1784 inside the body of the for loop.
1785 The number of words must come out even; that is, if there are three
1786 iteration variables, the number of words provided must be a multiple
1789 Comments begin with a hash
1791 character, anywhere but in a shell
1792 command line, and continue to the end of an unescaped new line.
1793 .Sh SPECIAL SOURCES (ATTRIBUTES)
1794 .Bl -tag -width .IGNOREx
1796 Target is never out of date, but always execute commands anyway.
1798 Ignore any errors from the commands associated with this target, exactly
1799 as if they all were preceded by a dash
1801 .\" .It Ic .INVISIBLE
1806 Mark all sources of this target as being up-to-date.
1808 Execute the commands associated with this target even if the
1812 options were specified.
1813 Normally used to mark recursive
1816 Create a meta file for the target, even if it is flagged as
1821 Usage in conjunction with
1823 is the most likely case.
1824 In "meta" mode, the target is out-of-date if the meta file is missing.
1826 Do not create a meta file for the target.
1827 Meta files are also not created for
1834 Ignore differences in commands when deciding if target is out of date.
1835 This is useful if the command contains a value which always changes.
1836 If the number of commands change, though, the target will still be out of date.
1837 The same effect applies to any command line that uses the variable
1839 which can be used for that purpose even when not otherwise needed or desired:
1840 .Bd -literal -offset indent
1842 skip-compare-for-some:
1843 @echo this will be compared
1844 @echo this will not ${.OODATE:M.NOMETA_CMP}
1845 @echo this will also be compared
1850 pattern suppresses any expansion of the unwanted variable.
1852 Do not search for the target in the directories specified by
1857 selects the first target it encounters as the default target to be built
1858 if no target was specified.
1859 This source prevents this target from being selected.
1861 If a target is marked with this attribute and
1863 can't figure out how to create it, it will ignore this fact and assume
1864 the file isn't needed or already exists.
1867 correspond to an actual file; it is always considered to be out of date,
1868 and will not be created with the
1871 Suffix-transformation rules are not applied to
1877 is interrupted, it normally removes any partially made targets.
1878 This source prevents the target from being removed.
1883 Do not echo any of the commands associated with this target, exactly
1884 as if they all were preceded by an at sign
1887 Turn the target into
1890 When the target is used as a source for another target, the other target
1891 acquires the commands, sources, and attributes (except for
1895 If the target already has commands, the
1897 target's commands are appended
1904 target commands to the target.
1908 appears in a dependency line, the sources that precede it are
1909 made before the sources that succeed it in the line.
1910 Since the dependents of files are not made until the file itself
1911 could be made, this also stops the dependents being built unless they
1912 are needed for another branch of the dependency tree.
1925 the output is always
1931 The ordering imposed by
1933 is only relevant for parallel makes.
1936 Special targets may not be included with other targets, i.e. they must be
1937 the only target specified.
1938 .Bl -tag -width .BEGINx
1940 Any command lines attached to this target are executed before anything
1945 rule for any target (that was used only as a
1948 can't figure out any other way to create.
1949 Only the shell script is used.
1952 variable of a target that inherits
1955 to the target's own name.
1957 Any command lines attached to this target are executed after everything
1960 Any command lines attached to this target are executed when another target fails.
1963 variable is set to the target that failed.
1965 .Ic MAKE_PRINT_VAR_ON_ERROR .
1967 Mark each of the sources with the
1970 If no sources are specified, this is the equivalent of specifying the
1976 is interrupted, the commands for this target will be executed.
1978 If no target is specified when
1980 is invoked, this target will be built.
1982 This target provides a way to specify flags for
1984 when the makefile is used.
1985 The flags are as if typed to the shell, though the
1989 .\" XXX: NOT YET!!!!
1990 .\" .It Ic .NOTPARALLEL
1991 .\" The named targets are executed in non parallel mode.
1992 .\" If no targets are
1993 .\" specified, then all targets are executed in non parallel mode.
1997 attribute to any specified sources.
1999 Disable parallel mode.
2003 for compatibility with other pmake variants.
2005 The named targets are made in sequence.
2006 This ordering does not add targets to the list of targets to be made.
2007 Since the dependents of a target do not get built until the target itself
2008 could be built, unless
2010 is built by another part of the dependency graph,
2011 the following is a dependency loop:
2017 The ordering imposed by
2019 is only relevant for parallel makes.
2020 .\" XXX: NOT YET!!!!
2021 .\" .It Ic .PARALLEL
2022 .\" The named targets are executed in parallel mode.
2023 .\" If no targets are
2024 .\" specified, then all targets are executed in parallel mode.
2026 The sources are directories which are to be searched for files not
2027 found in the current directory.
2028 If no sources are specified, any previously specified directories are
2030 If the source is the special
2032 target, then the current working
2033 directory is searched last.
2034 .It Ic .PATH. Ns Va suffix
2037 but applies only to files with a particular suffix.
2038 The suffix must have been previously declared with
2043 attribute to any specified sources.
2047 attribute to any specified sources.
2048 If no sources are specified, the
2050 attribute is applied to every
2055 will use to execute commands.
2056 The sources are a set of
2059 .Bl -tag -width hasErrCtls
2061 This is the minimal specification, used to select one of the builtin
2068 Specifies the path to the shell.
2070 Indicates whether the shell supports exit on error.
2072 The command to turn on error checking.
2074 The command to disable error checking.
2076 The command to turn on echoing of commands executed.
2078 The command to turn off echoing of commands executed.
2080 The output to filter after issuing the
2083 It is typically identical to
2086 The flag to pass the shell to enable error checking.
2088 The flag to pass the shell to enable command echoing.
2090 The string literal to pass the shell that results in a single newline
2091 character when used outside of any quoting characters.
2095 \&.SHELL: name=ksh path=/bin/ksh hasErrCtl=true \e
2096 check="set \-e" ignore="set +e" \e
2097 echo="set \-v" quiet="set +v" filter="set +v" \e
2098 echoFlag=v errFlag=e newline="'\en'"
2103 attribute to any specified sources.
2104 If no sources are specified, the
2106 attribute is applied to every
2107 command in the file.
2109 This target gets run when a dependency file contains stale entries, having
2111 set to the name of that dependency file.
2113 Each source specifies a suffix to
2115 If no sources are specified, any previously specified suffixes are deleted.
2116 It allows the creation of suffix-transformation rules.
2122 cc \-o ${.TARGET} \-c ${.IMPSRC}
2127 uses the following environment variables, if they exist:
2133 .Ev MAKEOBJDIRPREFIX ,
2139 .Ev MAKEOBJDIRPREFIX
2142 may only be set in the environment or on the command line to
2144 and not as makefile variables;
2145 see the description of
2149 .Bl -tag -width /usr/share/mk -compact
2151 list of dependencies
2153 list of dependencies
2155 list of dependencies
2159 system makefile directory
2162 The basic make syntax is compatible between different versions of make;
2163 however the special variables, variable modifiers and conditionals are not.
2165 An incomplete list of changes in older versions of
2168 The way that .for loop variables are substituted changed after
2170 so that they still appear to be variable expansions.
2171 In particular this stops them being treated as syntax, and removes some
2172 obscure problems using them in .if statements.
2174 The way that parallel makes are scheduled changed in
2176 so that .ORDER and .WAIT apply recursively to the dependent nodes.
2177 The algorithms used may change again in the future.
2178 .Ss Other make dialects
2179 Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not
2180 support most of the features of
2182 as described in this manual.
2184 .Bl -bullet -offset indent
2190 declarations and most functionality pertaining to parallelization.
2191 (GNU make supports parallelization but lacks these features needed to
2192 control it effectively.)
2194 Directives, including for loops and conditionals and most of the
2195 forms of include files.
2196 (GNU make has its own incompatible and less powerful syntax for
2199 All built-in variables that begin with a dot.
2201 Most of the special sources and targets that begin with a dot,
2202 with the notable exception of
2208 Variable modifiers, except for the
2210 string substitution, which does not portably support globbing with
2212 and historically only works on declared suffixes.
2216 variable even in its short form; most makes support this functionality
2217 but its name varies.
2220 Some features are somewhat more portable, such as assignment with
2227 functionality is based on an older feature
2229 found in GNU make and many versions of SVR4 make; however,
2230 historically its behavior is too ill-defined (and too buggy) to rely
2237 variables are more or less universally portable, as is the
2240 Basic use of suffix rules (for files only in the current directory,
2241 not trying to chain transformations together, etc.) is also reasonably
2247 is derived from NetBSD
2249 It uses autoconf to facilitate portability to other platforms.
2257 implementation is based on Adam De Boor's pmake program which was written
2258 for Sprite at Berkeley.
2259 It was designed to be a parallel distributed make running jobs on different
2260 machines using a daemon called
2263 Historically the target/dependency
2265 has been used to FoRCe rebuilding (since the target/dependency
2266 does not exist... unless someone creates an
2272 syntax is difficult to parse without actually acting of the data.
2273 For instance finding the end of a variable use should involve scanning each
2274 the modifiers using the correct terminator for each field.
2277 just counts {} and () in order to find the end of a variable expansion.
2279 There is no way of escaping a space character in a filename.