1BMAKE(1) FreeBSD General Commands Manual
2BMAKE(1)
3[1mNAME[0m
5 [1mbmake [22m— maintain program dependencies
6[1mSYNOPSIS[0m
8 [1mbmake [22m[[1m‐BeikNnqrSstWwX[22m] [[1m‐C [4m[22mdirecto‐
9ry[24m] [[1m‐D [4m[22mvariable[24m] [[1m‐d [4m[22mflags[24m]
10 [[1m‐f [4m[22mmakefile[24m] [[1m‐I [4m[22mdirecto‐
11ry[24m] [[1m‐J [4m[22mprivate[24m] [[1m‐j [4m[22mmax_jobs[24m]
12 [[1m‐m [4m[22mdirectory[24m] [[1m‐T [4m[22mfile[24m]
13[[1m‐V [4m[22mvariable[24m] [[1m‐v [4m[22mvariable[24m]
14 [[4mvariable=value[24m] [[4mtarget[24m [4m...[24m]
15[1mDESCRIPTION[0m
17 [1mbmake [22mis a program designed to simplify the mainte‐
18nance of other pro‐
19 grams. Its input is a list of specifications as to the
20files upon which
21 programs and other files depend. If no [1m‐f [4m[22mmake‐
22file[24m makefile option is
23 given, [1mbmake [22mwill try to open ‘[4mmakefile[24m’ then
24‘[4mMakefile[24m’ in order to find
25 the specifications. If the file ‘[4m.depend[24m’ exists, it
26is read (see
27 mkdep(1)).
28 This manual page is intended as a reference document only.
30For a more
31 thorough description of [1mbmake [22mand makefiles, please
32refer to [4mPMake[24m [4m‐[24m [4mA[0m
33 [4mTutorial[24m.
34 [1mbmake [22mwill prepend the contents of the [4mMAKE‐
36FLAGS[24m environment variable to
37 the command line arguments before parsing them.
38 The options are as follows:
40 [1m‐B [22mTry to be backwards compatible by executing a
42single shell per
43 command and by executing the commands to make the
44sources of a
45 dependency line in sequence.
46 [1m‐C [4m[22mdirectory[0m
48 Change to [4mdirectory[24m before reading the make‐
49files or doing any‐
50 thing else. If multiple [1m‐C [22moptions are spec‐
51ified, each is inter‐
52 preted relative to the previous one: [1m‐C
53[4m[22m/[24m [1m‐C [4m[22metc[24m is equivalent to
54 [1m‐C [4m[22m/etc[24m.
55 [1m‐D [4m[22mvariable[0m
57 Define [4mvariable[24m to be 1, in the global scope.
58 [1m‐d [4m[22m[‐]flags[0m
60 Turn on debugging, and specify which portions of
61[1mbmake [22mare to
62 print debugging information. Unless the flags are
63preceded by
64 ‘‐’ they are added to the [4mMAKEFLAGS[24m environ‐
65ment variable and will
66 be processed by any child make processes. By de‐
67fault, debugging
68 information is printed to standard error, but this
69can be changed
70 using the [4mF[24m debugging flag. The debugging
71output is always un‐
72 buffered; in addition, if debugging is enabled but
73debugging out‐
74 put is not directed to standard output, then the
75standard output
76 is line buffered. [4mFlags[24m is one or more of
77the following:
78 [4mA[24m Print all possible debugging informa‐
80tion; equivalent to
81 specifying all of the debugging flags.
82 [4ma[24m Print debugging information about ar‐
84chive searching and
85 caching.
86 [4mC[24m Print debugging information about
88current working direc‐
89 tory.
90 [4mc[24m Print debugging information about
92conditional evaluation.
93 [4md[24m Print debugging information about di‐
95rectory searching and
96 caching.
97 [4me[24m Print debugging information about
99failed commands and
100 targets.
101 [4mF[24m[[1m+[22m][4mfilename[0m
103 Specify where debugging output is written.
104This must be
105 the last flag, because it consumes the re‐
106mainder of the
107 argument. If the character immediately af‐
108ter the ‘F’
109 flag is ‘+’, then the file will be opened in
110append mode;
111 otherwise the file will be overwritten. If
112the file name
113 is ‘stdout’ or ‘stderr’ then debugging out‐
114put will be
115 written to the standard output or standard
116error output
117 file descriptors respectively (and the ‘+’
118option has no
119 effect). Otherwise, the output will be
120written to the
121 named file. If the file name ends ‘.%d’
122then the ‘%d’ is
123 replaced by the pid.
124 [4mf[24m Print debugging information about
126loop evaluation.
127 [4mg1[24m Print the input graph before making
129anything.
130 [4mg2[24m Print the input graph after making
132everything, or before
133 exiting on error.
134 [4mg3[24m Print the input graph before exiting
136on error.
137 [4mh[24m Print debugging information about
139hash table operations.
140 [4mj[24m Print debugging information about
142running multiple
143 shells.
144 [4mL[24m Turn on lint checks. This will throw
146errors for variable
147 assignments that do not parse correctly, at
148the time of
149 assignment so the file and line number are
150available.
151 [4ml[24m Print commands in Makefiles regard‐
153less of whether or not
154 they are prefixed by ‘@’ or other "quiet"
155flags. Also
156 known as "loud" behavior.
157 [4mM[24m Print debugging information about
159"meta" mode decisions
160 about targets.
161 [4mm[24m Print debugging information about
163making targets, includ‐
164 ing modification dates.
165 [4mn[24m Don’t delete the temporary command
167scripts created when
168 running commands. These temporary scripts
169are created in
170 the directory referred to by the TMPDIR en‐
171vironment vari‐
172 able, or in [4m/tmp[24m if TMPDIR is unset
173or set to the empty
174 string. The temporary scripts are created
175by mkstemp(3),
176 and have names of the form
177[4mmakeXXXXXX[24m. [4mNOTE[24m: This can
178 create many files in TMPDIR or [4m/tmp[24m,
179so use with care.
180 [4mp[24m Print debugging information about
182makefile parsing.
183 [4ms[24m Print debugging information about
185suffix‐transformation
186 rules.
187 [4mt[24m Print debugging information about
189target list mainte‐
190 nance.
191 [4mV[24m Force the [1m‐V [22moption to print
193raw values of variables,
194 overriding the default behavior set via
195 [4m.MAKE.EXPAND_VARIABLES[24m.
196 [4mv[24m Print debugging information about
198variable assignment.
199 [4mx[24m Run shell commands with [1m‐x [22mso
201the actual commands are
202 printed as they are executed.
203 [1m‐e [22mSpecify that environment variables override
205macro assignments
206 within makefiles.
207 [1m‐f [4m[22mmakefile[0m
209 Specify a makefile to read instead of the default
210‘[4mmakefile[24m’. If
211 [4mmakefile[24m is ‘[1m‐[22m’, standard input is
212read. Multiple makefiles may
213 be specified, and are read in the order specified.
214 [1m‐I [4m[22mdirectory[0m
216 Specify a directory in which to search for makefiles
217and included
218 makefiles. The system makefile directory (or direc‐
219tories, see
220 the [1m‐m [22moption) is automatically included as
221part of this list.
222 [1m‐i [22mIgnore non‐zero exit of shell commands in the
224makefile. Equiva‐
225 lent to specifying ‘[1m‐[22m’ before each command
226line in the makefile.
227 [1m‐J [4m[22mprivate[0m
229 This option should [4mnot[24m be specified by the
230user.
231 When the [4mj[24m option is in use in a recursive
233build, this option is
234 passed by a make to child makes to allow all the
235make processes
236 in the build to cooperate to avoid overloading the
237system.
238 [1m‐j [4m[22mmax_jobs[0m
240 Specify the maximum number of jobs that [1mbmake
241[22mmay have running at
242 any one time. The value is saved in
243[4m.MAKE.JOBS[24m. Turns compati‐
244 bility mode off, unless the [4mB[24m flag is also
245specified. When com‐
246 patibility mode is off, all commands associated with
247a target are
248 executed in a single shell invocation as opposed to
249the tradi‐
250 tional one shell invocation per line. This can
251break traditional
252 scripts which change directories on each command in‐
253vocation and
254 then expect to start with a fresh environment on the
255next line.
256 It is more efficient to correct the scripts rather
257than turn
258 backwards compatibility on.
259 [1m‐k [22mContinue processing after errors are encoun‐
261tered, but only on
262 those targets that do not depend on the target whose
263creation
264 caused the error.
265 [1m‐m [4m[22mdirectory[0m
267 Specify a directory in which to search for sys.mk
268and makefiles
269 included via the <[4mfile[24m>‐style include state‐
270ment. The [1m‐m [22moption
271 can be used multiple times to form a search path.
272This path will
273 override the default system include path:
274/usr/share/mk. Fur‐
275 thermore the system include path will be appended to
276the search
277 path used for "[4mfile[24m"‐style include statements
278(see the [1m‐I [22mop‐
279 tion).
280 If a file or directory name in the [1m‐m [22margu‐
282ment (or the
283 MAKESYSPATH environment variable) starts with the
284string ".../"
285 then [1mbmake [22mwill search for the specified file
286or directory named
287 in the remaining part of the argument string. The
288search starts
289 with the current directory of the Makefile and then
290works upward
291 towards the root of the file system. If the search
292is success‐
293 ful, then the resulting directory replaces the
294".../" specifica‐
295 tion in the [1m‐m [22margument. If used, this fea‐
296ture allows [1mbmake [22mto
297 easily search in the current source tree for custom‐
298ized sys.mk
299 files (e.g., by using ".../mk/sys.mk" as an argu‐
300ment).
301 [1m‐n [22mDisplay the commands that would have been ex‐
303ecuted, but do not
304 actually execute them unless the target depends on
305the .MAKE spe‐
306 cial source (see below) or the command is prefixed
307with ‘[1m+[22m’.
308 [1m‐N [22mDisplay the commands which would have been
310executed, but do not
311 actually execute any of them; useful for debugging
312top‐level
313 makefiles without descending into subdirectories.
314 [1m‐q [22mDo not execute any commands, but exit 0 if
316the specified targets
317 are up‐to‐date and 1, otherwise.
318 [1m‐r [22mDo not use the built‐in rules specified in
320the system makefile.
321 [1m‐S [22mStop processing if an error is encountered.
323This is the default
324 behavior and the opposite of [1m‐k[22m.
325 [1m‐s [22mDo not echo any commands as they are execut‐
327ed. Equivalent to
328 specifying ‘[1m@[22m’ before each command line in
329the makefile.
330 [1m‐T [4m[22mtracefile[0m
332 When used with the [1m‐j [22mflag, append a trace
333record to [4mtracefile[0m
334 for each job started and completed.
335 [1m‐t [22mRather than re‐building a target as specified
337in the makefile,
338 create it or update its modification time to make it
339appear up‐
340 to‐date.
341 [1m‐V [4m[22mvariable[0m
343 Print the value of [4mvariable[24m. Do not build
344any targets. Multiple
345 instances of this option may be specified; the vari‐
346ables will be
347 printed one per line, with a blank line for each
348null or unde‐
349 fined variable. The value printed is extracted from
350the global
351 scope after all makefiles have been read. By de‐
352fault, the raw
353 variable contents (which may include additional un‐
354expanded vari‐
355 able references) are shown. If [4mvariable[24m con‐
356tains a ‘$’ then the
357 value will be recursively expanded to its complete
358resultant text
359 before printing. The expanded value will also be
360printed if
361 [4m.MAKE.EXPAND_VARIABLES[24m is set to true and the
362[1m‐dV [22moption has not
363 been used to override it. Note that loop‐local and
364target‐local
365 variables, as well as values taken temporarily by
366global vari‐
367 ables during makefile processing, are not accessible
368via this op‐
369 tion. The [1m‐dv [22mdebug mode can be used to see
370these at the cost of
371 generating substantial extraneous output.
372 [1m‐v [4m[22mvariable[0m
374 Like [1m‐V [22mbut the variable is always expanded
375to its complete
376 value.
377 [1m‐W [22mTreat any warnings during makefile parsing as
379errors.
380 [1m‐w [22mPrint entering and leaving directory mes‐
382sages, pre and post pro‐
383 cessing.
384 [1m‐X [22mDon’t export variables passed on the command
386line to the environ‐
387 ment individually. Variables passed on the command
388line are
389 still exported via the [4mMAKEFLAGS[24m environment
390variable. This op‐
391 tion may be useful on systems which have a small
392limit on the
393 size of command arguments.
394 [4mvariable=value[0m
396 Set the value of the variable [4mvariable[24m to
397[4mvalue[24m. Normally, all
398 values passed on the command line are also exported
399to sub‐makes
400 in the environment. The [1m‐X [22mflag disables
401this behavior. Vari‐
402 able assignments should follow options for POSIX
403compatibility
404 but no ordering is enforced.
405 There are seven different types of lines in a makefile: file
407dependency
408 specifications, shell commands, variable assignments, in‐
409clude statements,
410 conditional directives, for loops, and comments.
411 In general, lines may be continued from one line to the next
413by ending
414 them with a backslash (‘\[u2019]). The trailing newline
415character and initial
416 whitespace on the following line are compressed into a sin‐
417gle space.
418[1mFILE DEPENDENCY SPECIFICATIONS[0m
420 Dependency lines consist of one or more targets, an opera‐
421tor, and zero or
422 more sources. This creates a relationship where the targets
423“depend” on
424 the sources and are customarily created from them. A target
425is consid‐
426 ered out‐of‐date if it does not exist, or if its modifica‐
427tion time is
428 less than that of any of its sources. An out‐of‐date target
429will be re‐
430 created, but not until all sources have been examined and
431themselves re‐
432 created as needed. Three operators may be used:
433 [1m: [22mMany dependency lines may name this target but
435only one may have
436 attached shell commands. All sources named in all de‐
437pendency lines
438 are considered together, and if needed the attached
439shell commands
440 are run to create or re‐create the target. If [1mb‐
441make [22mis inter‐
442 rupted, the target is removed.
443 [1m! [22mThe same, but the target is always re‐created
445whether or not it is
446 out of date.
447 [1m:: [22mAny dependency line may have attached shell
449commands, but each one
450 is handled independently: its sources are considered
451and the at‐
452 tached shell commands are run if the target is out of
453date with re‐
454 spect to (only) those sources. Thus, different groups
455of the at‐
456 tached shell commands may be run depending on the cir‐
457cumstances.
458 Furthermore, unlike [1m:, [22mfor dependency lines
459with no sources, the
460 attached shell commands are always run. Also unlike
461[1m:, [22mthe target
462 will not be removed if [1mbmake [22mis interrupted.
463 All dependency lines mentioning a particular target must use
464the same op‐
465 erator.
466 Targets and sources may contain the shell wildcard values
468‘?’, ‘*’, ‘[]’,
469 and ‘{}’. The values ‘?’, ‘*’, and ‘[]’ may only be used as
470part of the
471 final component of the target or source, and must be used to
472describe ex‐
473 isting files. The value ‘{}’ need not necessarily be used
474to describe
475 existing files. Expansion is in directory order, not alpha‐
476betically as
477 done in the shell.
478[1mSHELL COMMANDS[0m
480 Each target may have associated with it one or more lines of
481shell com‐
482 mands, normally used to create the target. Each of the
483lines in this
484 script [4mmust[24m be preceded by a tab. (For historical
485reasons, spaces are
486 not accepted.) While targets can appear in many dependency
487lines if de‐
488 sired, by default only one of these rules may be followed by
489a creation
490 script. If the ‘[1m::[22m’ operator is used, however, all
491rules may include
492 scripts and the scripts are executed in the order found.
493 Each line is treated as a separate shell command, unless the
495end of line
496 is escaped with a backslash (‘\[u2019]) in which case that
497line and the next
498 are combined. If the first characters of the command are
499any combination
500 of ‘[1m@[22m’, ‘[1m+[22m’, or ‘[1m‐[22m’, the command is
501treated specially. A ‘[1m@[22m’ causes the
502 command not to be echoed before it is executed. A
503‘[1m+[22m’ causes the command
504 to be executed even when [1m‐n [22mis given. This is simi‐
505lar to the effect of
506 the .MAKE special source, except that the effect can be lim‐
507ited to a sin‐
508 gle line of a script. A ‘[1m‐[22m’ in compatibility mode
509causes any non‐zero
510 exit status of the command line to be ignored.
511 When [1mbmake [22mis run in jobs mode with [1m‐j
513[4m[22mmax_jobs[24m, the entire script for
514 the target is fed to a single instance of the shell. In
515compatibility
516 (non‐jobs) mode, each command is run in a separate process.
517If the com‐
518 mand contains any shell meta characters
519(‘#=|^(){};&<>*?[]:$‘\n’) it
520 will be passed to the shell; otherwise [1mbmake [22mwill at‐
521tempt direct execu‐
522 tion. If a line starts with ‘[1m‐[22m’ and the shell has
523ErrCtl enabled then
524 failure of the command line will be ignored as in compati‐
525bility mode.
526 Otherwise ‘[1m‐[22m’ affects the entire job; the script will
527stop at the first
528 command line that fails, but the target will not be deemed
529to have
530 failed.
531 Makefiles should be written so that the mode of [1mbmake
533[22moperation does not
534 change their behavior. For example, any command which needs
535to use “cd”
536 or “chdir” without potentially changing the directory for
537subsequent com‐
538 mands should be put in parentheses so it executes in a sub‐
539shell. To
540 force the use of one shell, escape the line breaks so as to
541make the
542 whole script one command. For example:
543 avoid‐chdir‐side‐effects:
545 @echo Building $@ in ‘pwd‘
546 @(cd ${.CURDIR} && ${MAKE} $@)
547 @echo Back in ‘pwd‘
548 ensure‐one‐shell‐regardless‐of‐mode:
550 @echo Building $@ in ‘pwd‘;
551(cd ${.CURDIR} && ${MAKE} $@); echo Back in
552‘pwd‘
553 Since [1mbmake [22mwill chdir(2) to ‘[4m.OBJDIR[24m’ before
555executing any targets, each
556 child process starts with that as its current working direc‐
557tory.
558[1mVARIABLE ASSIGNMENTS[0m
560 Variables in make are much like variables in the shell, and,
561by tradi‐
562 tion, consist of all upper‐case letters.
563 [1mVariable assignment modifiers[0m
565 The five operators that can be used to assign values to
566variables are as
567 follows:
568 [1m= [22mAssign the value to the variable. Any previ‐
570ous value is overrid‐
571 den.
572 [1m+= [22mAppend the value to the current value of the
574variable.
575 [1m?= [22mAssign the value to the variable if it is not
577already defined.
578 [1m:= [22mAssign with expansion, i.e. expand the value
580before assigning it
581 to the variable. Normally, expansion is not done
582until the vari‐
583 able is referenced. [4mNOTE[24m: References to un‐
584defined variables are
585 [4mnot[24m expanded. This can cause problems when
586variable modifiers
587 are used.
588 [1m!= [22mExpand the value and pass it to the shell for
590execution and as‐
591 sign the result to the variable. Any newlines in
592the result are
593 replaced with spaces.
594 Any white‐space before the assigned [4mvalue[24m is removed;
596if the value is be‐
597 ing appended, a single space is inserted between the previ‐
598ous contents of
599 the variable and the appended value.
600 Variables are expanded by surrounding the variable name with
602either curly
603 braces (‘{}’) or parentheses (‘()’) and preceding it with a
604dollar sign
605 (‘$’). If the variable name contains only a single letter,
606the surround‐
607 ing braces or parentheses are not required. This shorter
608form is not
609 recommended.
610 If the variable name contains a dollar, then the name itself
612is expanded
613 first. This allows almost arbitrary variable names, however
614names con‐
615 taining dollar, braces, parentheses, or whitespace are real‐
616ly best
617 avoided!
618 If the result of expanding a variable contains a dollar sign
620(‘$’) the
621 string is expanded again.
622 Variable substitution occurs at three distinct times, de‐
624pending on where
625 the variable is being used.
626 1. Variables in dependency lines are expanded as the line
628is read.
629 2. Variables in shell commands are expanded when the shell
631command is
632 executed.
633 3. “.for” loop index variables are expanded on each loop
635iteration.
636 Note that other variables are not expanded inside loops
637so the fol‐
638 lowing example code:
639 .for i in 1 2 3
642 a+= ${i}
643 j= ${i}
644 b+= ${j}
645 .endfor
646 all:
648 @echo ${a}
649 @echo ${b}
650 will print:
652 1 2 3
654 3 3 3
655 Because while ${a} contains “1 2 3” after the loop is
657executed, ${b}
658 contains “${j} ${j} ${j}” which expands to “3 3 3”
659since after the
660 loop completes ${j} contains “3”.
661 [1mVariable classes[0m
663 The four different classes of variables (in order of in‐
664creasing prece‐
665 dence) are:
666 Environment variables
668 Variables defined as part of [1mbmake[22m’s environ‐
669ment.
670 Global variables
672 Variables defined in the makefile or in included
673makefiles.
674 Command line variables
676 Variables defined as part of the command line.
677 Local variables
679 Variables that are defined specific to a certain
680target.
681 Local variables can be set on a dependency line, if
683 [4m.MAKE.TARGET_LOCAL_VARIABLES[24m is not set to ‘false’.
684The rest of the line
685 (which will already have had global variables expanded) is
686the variable
687 value. For example:
688 COMPILER_WRAPPERS= ccache distcc icecc
690 ${OBJS}: .MAKE.META.CMP_FILTER=${COMPILER_WRAP‐
692PERS:S,^,N,}
693 Only the targets ‘${OBJS}’ will be impacted by that filter
695(in "meta"
696 mode) and simply enabling/disabling any of the compiler
697wrappers will not
698 render all of those targets out‐of‐date.
699 [4mNOTE[24m: target‐local variable assignments behave dif‐
701ferently in that;
702 [1m+= [22mOnly appends to a previous local as‐
704signment for the same
705 target and variable.
706 [1m:= [22mIs redundant with respect to global
708variables, which have
709 already been expanded.
710 The seven built‐in local variables are as follows:
712 [4m.ALLSRC[24m The list of all sources for this tar‐
714get; also known as
715 ‘[4m>[24m’.
716 [4m.ARCHIVE[24m The name of the archive file; also
718known as ‘[4m![24m’.
719 [4m.IMPSRC[24m In suffix‐transformation rules, the
721name/path of the
722 source from which the target is to be trans‐
723formed (the
724 “implied” source); also known as ‘[4m<[24m’.
725It is not defined
726 in explicit rules.
727 [4m.MEMBER[24m The name of the archive member; also
729known as ‘[4m%[24m’.
730 [4m.OODATE[24m The list of sources for this target
732that were deemed out‐
733 of‐date; also known as ‘[4m?[24m’.
734 [4m.PREFIX[24m The file prefix of the target, con‐
736taining only the file
737 portion, no suffix or preceding directory
738components;
739 also known as ‘[4m*[24m’. The suffix must
740be one of the known
741 suffixes declared with [1m.SUFFIXES [22mor
742it will not be recog‐
743 nized.
744 [4m.TARGET[24m The name of the target; also known as
746‘[4m@[24m’. For compati‐
747 bility with other makes this is an alias for
748[1m.ARCHIVE [22min
749 archive member rules.
750 The shorter forms (‘[4m>[24m’, ‘[4m![24m’, ‘[4m<[24m’,
752‘[4m%[24m’, ‘[4m?[24m’, ‘[4m*[24m’, and ‘[4m@[24m’) are permitted
753 for backward compatibility with historical makefiles and
754legacy POSIX
755 make and are not recommended.
756 Variants of these variables with the punctuation followed
758immediately by
759 ‘D’ or ‘F’, e.g. ‘[4m$(@D)[24m’, are legacy forms equiva‐
760lent to using the ‘:H’
761 and ‘:T’ modifiers. These forms are accepted for compati‐
762bility with AT&T
763 System V UNIX makefiles and POSIX but are not recommended.
764 Four of the local variables may be used in sources on depen‐
766dency lines
767 because they expand to the proper value for each target on
768the line.
769 These variables are ‘[4m.TARGET[24m’, ‘[4m.PREFIX[24m’,
770‘[4m.ARCHIVE[24m’, and ‘[4m.MEMBER[24m’.
771 [1mAdditional built‐in variables[0m
773 In addition, [1mbmake [22msets or knows about the following
774variables:
775 [4m$[24m A single dollar sign ‘$’, i.e. ‘$$’
777expands to a single
778 dollar sign.
779 [4m.ALLTARGETS[24m The list of all targets encountered
781in the Makefile. If
782 evaluated during Makefile parsing, lists on‐
783ly those tar‐
784 gets encountered thus far.
785 [4m.CURDIR[24m A path to the directory where [1mb‐
787make [22mwas executed. Refer
788 to the description of ‘PWD’ for more de‐
789tails.
790 [4m.INCLUDEDFROMDIR[0m
792 The directory of the file this Makefile was
793included
794 from.
795 [4m.INCLUDEDFROMFILE[0m
797 The filename of the file this Makefile was
798included from.
799 MAKE The name that [1mbmake [22mwas executed with
801([4margv[0][24m). For
802 compatibility [1mbmake [22malso sets
803[4m.MAKE[24m with the same value.
804 The preferred variable to use is the envi‐
805ronment variable
806 MAKE because it is more compatible with oth‐
807er versions of
808 [1mbmake [22mand cannot be confused with the
809special target with
810 the same name.
811 [4m.MAKE.DEPENDFILE[0m
813 Names the makefile (default ‘[4m.de‐
814pend[24m’) from which gener‐
815 ated dependencies are read.
816 [4m.MAKE.EXPAND_VARIABLES[0m
818 A boolean that controls the default behavior
819of the [1m‐V[0m
820 option. If true, variable values printed
821with [1m‐V [22mare
822 fully expanded; if false, the raw variable
823contents
824 (which may include additional unexpanded
825variable refer‐
826 ences) are shown.
827 [4m.MAKE.EXPORTED[24m The list of variables exported by
829[1mbmake[22m.
830 [4m.MAKE.JOBS[24m The argument to the [1m‐j [22moption.
832 [4m.MAKE.JOB.PREFIX[0m
834 If [1mbmake [22mis run with [4mj[24m then
835output for each target is
836 prefixed with a token ‘‐‐‐ target ‐‐‐’ the
837first part of
838 which can be controlled via
839[4m.MAKE.JOB.PREFIX[24m. If
840 [4m.MAKE.JOB.PREFIX[24m is empty, no token
841is printed.
842 For example:
843 .MAKE.JOB.PREFIX=${.new‐
844line}‐‐‐${.MAKE:T}[${.MAKE.PID}]
845 would produce tokens like ‘‐‐‐make[1234]
846target ‐‐‐’ mak‐
847 ing it easier to track the degree of paral‐
848lelism being
849 achieved.
850 .MAKE.TARGET_LOCAL_VARIABLES
852 If set to ‘false’, apparent variable assign‐
853ments in de‐
854 pendency lines are treated as normal
855sources.
856 MAKEFLAGS The environment variable ‘MAKEFLAGS’ may
858contain anything
859 that may be specified on [1mbmake[22m’s com‐
860mand line. Anything
861 specified on [1mbmake[22m’s command line is
862appended to the
863 ‘MAKEFLAGS’ variable which is then entered
864into the envi‐
865 ronment for all programs which [1mbmake
866[22mexecutes.
867 [4m.MAKE.LEVEL[24m The recursion depth of [1mbmake[22m.
869The initial instance of
870 [1mbmake [22mwill be 0, and an incremented
871value is put into the
872 environment to be seen by the next genera‐
873tion. This al‐
874 lows tests like: .if ${.MAKE.LEVEL} == 0 to
875protect
876 things which should only be evaluated in the
877initial in‐
878 stance of [1mbmake[22m.
879 [4m.MAKE.MAKEFILE_PREFERENCE[0m
881 The ordered list of makefile names (default
882‘[4mmakefile[24m’,
883 ‘[4mMakefile[24m’) that [1mbmake [22mwill
884look for.
885 [4m.MAKE.MAKEFILES[0m
887 The list of makefiles read by [1mbmake[22m,
888which is useful for
889 tracking dependencies. Each makefile is
890recorded only
891 once, regardless of the number of times
892read.
893 [4m.MAKE.MODE[24m Processed after reading all make‐
895files. Can affect the
896 mode that [1mbmake [22mruns in. It can con‐
897tain a number of key‐
898 words:
899 [4mcompat[24m Like [1m‐B[22m,
901puts [1mbmake [22minto "compat"
902 mode.
903 [4mmeta[24m Puts [1mbmake
905[22minto "meta" mode, where
906 meta files are created
907for each tar‐
908 get to capture the com‐
909mand run, the
910 output generated and if
911filemon(4)
912 is available, the sys‐
913tem calls which
914 are of interest to
915[1mbmake[22m. The cap‐
916 tured output can be
917very useful when
918 diagnosing errors.
919 [4mcurdirOk=[24m [4mbf[24m Normally
921[1mbmake [22mwill not create .meta
922 files in ‘[4m.CUR‐
923DIR[24m’. This can be
924 overridden by setting
925[4mbf[24m to a value
926 which represents True.
927 [4mmissing‐meta=[24m [4mbf[24m If
929[4mbf[24m is True, then a missing .meta
930 file makes the target
931out‐of‐date.
932 [4mmissing‐filemon=[24m [4mbf[24m If
934[4mbf[24m is True, then missing filemon
935 data makes the target
936out‐of‐date.
937 [4mnofilemon[24m Do not use file‐
939mon(4).
940 [4menv[24m For debugging,
942it can be useful to
943 include the environment
944in the .meta
945 file.
946 [4mverbose[24m If in "meta"
948mode, print a clue
949 about the target being
950built. This
951 is useful if the build
952is otherwise
953 running silently. The
954message
955 printed the value of:
956 [4m.MAKE.META.PRE‐
957FIX[24m.
958 [4mignore‐cmd[24m Some makefiles
960have commands which
961 are simply not stable.
962This keyword
963 causes them to be ig‐
964nored for deter‐
965 mining whether a target
966is out of
967 date in "meta" mode.
968See also
969 [1m.NOMETA_CMP[22m.
970 [4msilent=[24m [4mbf[24m If
972[4mbf[24m is True, when a .meta file is
973 created, mark the tar‐
974get [1m.SILENT[22m.
975 [4mrandomize‐targets[24m In both compat
977and parallel mode, do
978 not make the targets in
979the usual
980 order, but instead ran‐
981domize their
982 order. This mode can
983be used to de‐
984 tect undeclared depen‐
985dencies between
986 files.
987 [4m.MAKE.META.BAILIWICK[0m
989 In "meta" mode, provides a list of prefixes
990which match
991 the directories controlled by [1mbmake[22m.
992If a file that was
993 generated outside of [4m.OBJDIR[24m but
994within said bailiwick is
995 missing, the current target is considered
996out‐of‐date.
997 [4m.MAKE.META.CMP_FILTER[0m
999 In "meta" mode, it can (very rarely!) be
1000useful to filter
1001 command lines before comparison. This vari‐
1002able can be
1003 set to a set of modifiers that will be ap‐
1004plied to each
1005 line of the old and new command that differ,
1006if the fil‐
1007 tered commands still differ, the target is
1008considered
1009 out‐of‐date.
1010 [4m.MAKE.META.CREATED[0m
1012 In "meta" mode, this variable contains a
1013list of all the
1014 meta files updated. If not empty, it can be
1015used to
1016 trigger processing of
1017[4m.MAKE.META.FILES[24m.
1018 [4m.MAKE.META.FILES[0m
1020 In "meta" mode, this variable contains a
1021list of all the
1022 meta files used (updated or not). This list
1023can be used
1024 to process the meta files to extract depen‐
1025dency informa‐
1026 tion.
1027 [4m.MAKE.META.IGNORE_PATHS[0m
1029 Provides a list of path prefixes that should
1030be ignored;
1031 because the contents are expected to change
1032over time.
1033 The default list includes: ‘[4m/dev[24m
1034[4m/etc[24m [4m/proc[24m [4m/tmp[24m [4m/var/run[0m
1035 [4m/var/tmp[24m’
1036 [4m.MAKE.META.IGNORE_PATTERNS[0m
1038 Provides a list of patterns to match against
1039pathnames.
1040 Ignore any that match.
1041 [4m.MAKE.META.IGNORE_FILTER[0m
1043 Provides a list of variable modifiers to ap‐
1044ply to each
1045 pathname. Ignore if the expansion is an
1046empty string.
1047 [4m.MAKE.META.PREFIX[0m
1049 Defines the message printed for each meta
1050file updated in
1051 "meta verbose" mode. The default value is:
1052 Building ${.TARGET:H:tA}/${.TARGET:T}
1053 [4m.MAKEOVERRIDES[24m This variable is used to record the
1055names of variables
1056 assigned to on the command line, so that
1057they may be ex‐
1058 ported as part of ‘MAKEFLAGS’. This behav‐
1059ior can be dis‐
1060 abled by assigning an empty value to
1061‘[4m.MAKEOVERRIDES[24m’
1062 within a makefile. Extra variables can be
1063exported from
1064 a makefile by appending their names to
1065‘[4m.MAKEOVERRIDES[24m’.
1066 ‘MAKEFLAGS’ is re‐exported whenever
1067‘[4m.MAKEOVERRIDES[24m’ is
1068 modified.
1069 [4m.MAKE.PATH_FILEMON[0m
1071 If [1mbmake [22mwas built with filemon(4)
1072support, this is set
1073 to the path of the device node. This allows
1074makefiles to
1075 test for this support.
1076 [4m.MAKE.PID[24m The process‐id of [1mbmake[22m.
1078 [4m.MAKE.PPID[24m The parent process‐id of [1mb‐
1080make[22m.
1081 [4m.MAKE.SAVE_DOLLARS[0m
1083 value should be a boolean that controls
1084whether ‘$$’ are
1085 preserved when doing ‘:=’ assignments. The
1086default is
1087 false, for backwards compatibility. Set to
1088true for com‐
1089 patability with other makes. If set to
1090false, ‘$$’ be‐
1091 comes ‘$’ per normal evaluation rules.
1092 [4m.MAKE.UID[24m The user‐id running [1mbmake[22m.
1094 [4m.MAKE.GID[24m The group‐id running [1mbmake[22m.
1096 [4mMAKE_PRINT_VAR_ON_ERROR[0m
1098 When [1mbmake [22mstops due to an error, it
1099sets ‘[4m.ERROR_TARGET[24m’
1100 to the name of the target that failed,
1101‘[4m.ERROR_CMD[24m’ to
1102 the commands of the failed target, and in
1103"meta" mode, it
1104 also sets ‘[4m.ERROR_CWD[24m’ to the
1105getcwd(3), and
1106 ‘[4m.ERROR_META_FILE[24m’ to the path of the
1107meta file (if any)
1108 describing the failed target. It then
1109prints its name
1110 and the value of ‘[4m.CURDIR[24m’ as well as
1111the value of any
1112 variables named in ‘[4mMAKE_PRINT_VAR_ON_ER‐
1113ROR[24m’.
1114 [4m.newline[24m This variable is simply assigned a
1116newline character as
1117 its value. This allows expansions using the
1118[1m:@ [22mmodifier
1119 to put a newline between iterations of the
1120loop rather
1121 than a space. For example, the printing of
1122 ‘[4mMAKE_PRINT_VAR_ON_ERROR[24m’ could be
1123done as
1124 ${MAKE_PRINT_VAR_ON_ER‐
1125ROR:@v@$v=’${$v}’${.newline}@}.
1126 [4m.OBJDIR[24m A path to the directory where the
1128targets are built. Its
1129 value is determined by trying to chdir(2) to
1130the follow‐
1131 ing directories in order and using the first
1132match:
1133 1. ${MAKEOBJDIRPREFIX}${.CURDIR}
1135 (Only if ‘MAKEOBJDIRPREFIX’ is set in
1137the environ‐
1138 ment or on the command line.)
1139 2. ${MAKEOBJDIR}
1141 (Only if ‘MAKEOBJDIR’ is set in the en‐
1143vironment or
1144 on the command line.)
1145 3. ${.CURDIR}[4m/obj.[24m${MACHINE}
1147 4. ${.CURDIR}[4m/obj[0m
1149 5. [4m/usr/obj/[24m${.CURDIR}
1151 6. ${.CURDIR}
1153 Variable expansion is performed on the value
1155before it’s
1156 used, so expressions such as
1157 ${.CURDIR:S,^/usr/src,/var/obj,}
1158 may be used. This is especially useful with
1159 ‘MAKEOBJDIR’.
1160 ‘[4m.OBJDIR[24m’ may be modified in the
1162makefile via the special
1163 target ‘[1m.OBJDIR[22m’. In all cases,
1164[1mbmake [22mwill chdir(2) to
1165 the specified directory if it exists, and
1166set ‘[4m.OBJDIR[24m’
1167 and ‘PWD’ to that directory before executing
1168any targets.
1169 Except in the case of an explicit ‘[1m.OB‐
1171JDIR[22m’ target, [1mbmake[0m
1172 will check that the specified directory is
1173writable and
1174 ignore it if not. This check can be skipped
1175by setting
1176 the environment variable ‘MAKE_OB‐
1177JDIR_CHECK_WRITABLE’ to
1178 "no".
1179 [4m.PARSEDIR[24m A path to the directory of the cur‐
1181rent ‘[4mMakefile[24m’ being
1182 parsed.
1183 [4m.PARSEFILE[24m The basename of the current ‘[4mMake‐
1185file[24m’ being parsed.
1186 This variable and ‘[4m.PARSEDIR[24m’ are
1187both set only while the
1188 ‘[4mMakefiles[24m’ are being parsed. If you
1189want to retain
1190 their current values, assign them to a vari‐
1191able using as‐
1192 signment with expansion: (‘[1m:=[22m’).
1193 [4m.PATH[24m A variable that represents the list
1195of directories that
1196 [1mbmake [22mwill search for files. The
1197search list should be
1198 updated using the target ‘[4m.PATH[24m’
1199rather than the vari‐
1200 able.
1201 PWD Alternate path to the current directory.
1203[1mbmake [22mnormally
1204 sets ‘[4m.CURDIR[24m’ to the canonical path
1205given by getcwd(3).
1206 However, if the environment variable ‘PWD’
1207is set and
1208 gives a path to the current directory, then
1209[1mbmake [22msets
1210 ‘[4m.CURDIR[24m’ to the value of ‘PWD’ in‐
1211stead. This behavior
1212 is disabled if ‘MAKEOBJDIRPREFIX’ is set or
1213‘MAKEOBJDIR’
1214 contains a variable transform. ‘PWD’ is set
1215to the value
1216 of ‘[4m.OBJDIR[24m’ for all programs which
1217[1mbmake [22mexecutes.
1218 .SHELL The pathname of the shell used to run target
1220scripts. It
1221 is read‐only.
1222 .SUFFIXES The list of known suffixes. It is read‐on‐
1224ly.
1225 .TARGETS The list of targets explicitly specified on
1227the command
1228 line, if any.
1229 VPATH Colon‐separated (“:”) lists of directories
1231that [1mbmake[0m
1232 will search for files. The variable is sup‐
1233ported for
1234 compatibility with old make programs only,
1235use ‘[4m.PATH[24m’
1236 instead.
1237 [1mVariable modifiers[0m
1239 Variable expansion may be modified to select or modify each
1240word of the
1241 variable (where a “word” is white‐space delimited sequence
1242of charac‐
1243 ters). The general format of a variable expansion is as
1244follows:
1245 ${variable[:modifier[:...]]}
1247 Each modifier begins with a colon, which may be escaped with
1249a backslash
1250 (‘\[u2019]).
1251 A set of modifiers can be specified via a variable, as fol‐
1253lows:
1254 modifier_variable=modifier[:...]
1256 ${variable:${modifier_variable}[:...]}
1257 In this case the first modifier in the modifier_variable
1259does not start
1260 with a colon, since that must appear in the referencing
1261variable. If any
1262 of the modifiers in the modifier_variable contain a dollar
1263sign (‘$’),
1264 these must be doubled to avoid early expansion.
1265 The supported modifiers are:
1267 [1m:E [22mReplaces each word in the variable with its suf‐
1269fix.
1270 [1m:H [22mReplaces each word in the variable with every‐
1272thing but the last com‐
1273 ponent.
1274 [1m:M[4m[22mpattern[0m
1276 Selects only those words that match [4mpattern[24m.
1277The standard shell
1278 wildcard characters (‘*’, ‘?’, and ‘[]’) may be used.
1279The wildcard
1280 characters may be escaped with a backslash (‘\[u2019]).
1281As a consequence
1282 of the way values are split into words, matched, and
1283then joined, a
1284 construct like
1285 ${VAR:M*}
1286 will normalize the inter‐word spacing, removing all
1287leading and
1288 trailing space, and converting multiple consecutive
1289spaces to single
1290 spaces.
1291 [1m:N[4m[22mpattern[0m
1293 This is identical to ‘[1m:M[22m’, but selects all words
1294which do not match
1295 [4mpattern[24m.
1296 [1m:O [22mOrders every word in variable alphabetically.
1298 [1m:On [22mOrders every word in variable numerically. A
1300number followed by one
1301 of ‘k’, ‘M’ or ‘G’ is multiplied by the appropriate
1302factor (1024
1303 (k), 1048576 (M), or 1073741824 (G)). Both upper‐ and
1304lower‐case
1305 letters are accepted.
1306 [1m:Or [22mOrders every word in variable in reverse alpha‐
1308betical order.
1309 [1m:Orn[0m
1311 Orders every word in variable in reverse numerical or‐
1312der.
1313 [1m:Ox [22mShuffles the words in variable. The results
1315will be different each
1316 time you are referring to the modified variable; use
1317the assignment
1318 with expansion (‘[1m:=[22m’) to prevent such behavior.
1319For example,
1320 LIST= uno due tre quattro
1322 RANDOM_LIST= ${LIST:Ox}
1323 STATIC_RANDOM_LIST:= ${LIST:Ox}
1324 all:
1326 @echo "${RANDOM_LIST}"
1327 @echo "${RANDOM_LIST}"
1328 @echo "${STATIC_RANDOM_LIST}"
1329 @echo "${STATIC_RANDOM_LIST}"
1330 may produce output similar to:
1331 quattro due tre uno
1333 tre due quattro uno
1334 due uno quattro tre
1335 due uno quattro tre
1336 [1m:Q [22mQuotes every shell meta‐character in the vari‐
1338able, so that it can be
1339 passed safely to the shell.
1340 [1m:q [22mQuotes every shell meta‐character in the vari‐
1342able, and also doubles
1343 ‘$’ characters so that it can be passed safely through
1344recursive in‐
1345 vocations of [1mbmake[22m. This is equivalent to:
1346‘:S/&&/g:Q’.
1347 [1m:R [22mReplaces each word in the variable with every‐
1349thing but its suffix.
1350 [1m:range[=count][0m
1352 The value is an integer sequence representing the words
1353of the orig‐
1354 inal value, or the supplied [4mcount[24m.
1355 [1m:gmtime[=utc][0m
1357 The value is a format string for strftime(3), using gm‐
1358time(3). If a
1359 [4mutc[24m value is not provided or is 0, the current
1360time is used.
1361 [1m:hash[0m
1363 Computes a 32‐bit hash of the value and encode it as
1364hex digits.
1365 [1m:localtime[=utc][0m
1367 The value is a format string for strftime(3), using lo‐
1368caltime(3).
1369 If a [4mutc[24m value is not provided or is 0, the cur‐
1370rent time is used.
1371 [1m:tA [22mAttempts to convert variable to an absolute path
1373using realpath(3),
1374 if that fails, the value is unchanged.
1375 [1m:tl [22mConverts variable to lower‐case letters.
1377 [1m:ts[4m[22mc[0m
1379 Words in the variable are normally separated by a space
1380on expan‐
1381 sion. This modifier sets the separator to the charac‐
1382ter [4mc[24m. If [4mc[24m is
1383 omitted, then no separator is used. The common escapes
1384(including
1385 octal numeric codes) work as expected.
1386 [1m:tu [22mConverts variable to upper‐case letters.
1388 [1m:tW [22mCauses the value to be treated as a single word
1390(possibly containing
1391 embedded white space). See also ‘[1m:[*][22m’.
1392 [1m:tw [22mCauses the value to be treated as a sequence of
1394words delimited by
1395 white space. See also ‘[1m:[@][22m’.
1396 [1m:S[22m/[4mold_string[24m/[4mnew_string[24m/[[1m1gW[22m]
1398 Modifies the first occurrence of [4mold_string[24m in
1399each word of the
1400 variable’s value, replacing it with [4mnew_string[24m.
1401If a ‘g’ is ap‐
1402 pended to the last delimiter of the pattern, all occur‐
1403rences in each
1404 word are replaced. If a ‘1’ is appended to the last
1405delimiter of
1406 the pattern, only the first occurrence is affected. If
1407a ‘W’ is ap‐
1408 pended to the last delimiter of the pattern, then the
1409value is
1410 treated as a single word (possibly containing embedded
1411white space).
1412 If [4mold_string[24m begins with a caret (‘^’),
1413[4mold_string[24m is anchored at
1414 the beginning of each word. If [4mold_string[24m ends
1415with a dollar sign
1416 (‘$’), it is anchored at the end of each word. Inside
1417[4mnew_string[24m,
1418 an ampersand (‘&’) is replaced by [4mold_string[24m
1419(without any ‘^’ or
1420 ‘$’). Any character may be used as a delimiter for the
1421parts of the
1422 modifier string. The anchoring, ampersand and delim‐
1423iter characters
1424 may be escaped with a backslash (‘\[u2019]).
1425 Variable expansion occurs in the normal fashion inside
1427both
1428 [4mold_string[24m and [4mnew_string[24m with the single
1429exception that a backslash
1430 is used to prevent the expansion of a dollar sign
1431(‘$’), not a pre‐
1432 ceding dollar sign as is usual.
1433 [1m:C[22m/[4mpattern[24m/[4mreplacement[24m/[[1m1gW[22m]
1435 The [1m:C [22mmodifier is just like the [1m:S [22mmodi‐
1436fier except that the old and
1437 new strings, instead of being simple strings, are an
1438extended regu‐
1439 lar expression (see regex(3)) string [4mpattern[24m and
1440an ed(1)‐style
1441 string [4mreplacement[24m. Normally, the first occur‐
1442rence of the pattern
1443 [4mpattern[24m in each word of the value is substituted
1444with [4mreplacement[24m.
1445 The ‘1’ modifier causes the substitution to apply to at
1446most one
1447 word; the ‘g’ modifier causes the substitution to apply
1448to as many
1449 instances of the search pattern [4mpattern[24m as occur
1450in the word or
1451 words it is found in; the ‘W’ modifier causes the value
1452to be
1453 treated as a single word (possibly containing embedded
1454white space).
1455 As for the [1m:S [22mmodifier, the [4mpattern[24m and
1457[4mreplacement[24m are subjected to
1458 variable expansion before being parsed as regular ex‐
1459pressions.
1460 [1m:T [22mReplaces each word in the variable with its last
1462path component.
1463 [1m:u [22mRemoves adjacent duplicate words (like uniq(1)).
1465 [1m:?[4m[22mtrue_string[24m[1m:[4m[22mfalse_string[0m
1467 If the variable name (not its value), when parsed as a
1468.if condi‐
1469 tional expression, evaluates to true, return as its
1470value the
1471 [4mtrue_string[24m, otherwise return the
1472[4mfalse_string[24m. Since the variable
1473 name is used as the expression, :? must be the first
1474modifier after
1475 the variable name itself ‐ which will, of course, usu‐
1476ally contain
1477 variable expansions. A common error is trying to use
1478expressions
1479 like
1480 ${NUMBERS:M42:?match:no}
1481 which actually tests defined(NUMBERS), to determine if
1482any words
1483 match "42" you need to use something like:
1484 ${"${NUMBERS:M42}" != "":?match:no}.
1485 [4m:old_string=new_string[0m
1487 This is the AT&T System V UNIX style variable substitu‐
1488tion. It must
1489 be the last modifier specified. If [4mold_string[24m
1490or [4mnew_string[24m do not
1491 contain the pattern matching character [4m%[24m then it
1492is assumed that
1493 they are anchored at the end of each word, so only suf‐
1494fixes or en‐
1495 tire words may be replaced. Otherwise [4m%[24m is the
1496substring of
1497 [4mold_string[24m to be replaced in [4mnew_string[24m.
1498If only [4mold_string[24m con‐
1499 tains the pattern matching character [4m%[24m, and
1500[4mold_string[24m matches, then
1501 the result is the [4mnew_string[24m. If only the
1502[4mnew_string[24m contains the
1503 pattern matching character [4m%[24m, then it is not
1504treated specially and
1505 it is printed as a literal [4m%[24m on match. If there
1506is more than one
1507 pattern matching character ([4m%[24m) in either the
1508[4mnew_string[24m or
1509 [4mold_string[24m, only the first instance is treated
1510specially (as the
1511 pattern character); all subsequent instances are treat‐
1512ed as regular
1513 characters.
1514 Variable expansion occurs in the normal fashion inside
1516both
1517 [4mold_string[24m and [4mnew_string[24m with the single
1518exception that a backslash
1519 is used to prevent the expansion of a dollar sign
1520(‘$’), not a pre‐
1521 ceding dollar sign as is usual.
1522 [1m:@[4m[22mtemp[24m[1m@[4m[22mstring[24m[1m@[0m
1524 This is the loop expansion mechanism from the OSF De‐
1525velopment Envi‐
1526 ronment (ODE) make. Unlike [1m.for [22mloops, expan‐
1527sion occurs at the time
1528 of reference. Assigns [4mtemp[24m to each word in the
1529variable and evalu‐
1530 ates [4mstring[24m. The ODE convention is that
1531[4mtemp[24m should start and end
1532 with a period. For example.
1533 ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
1534 However a single character variable is often more read‐
1536able:
1537 ${MAKE_PRINT_VAR_ON_ERROR:@v@$v=’${$v}’${.new‐
1538line}@}
1539 [1m:_[=var][0m
1541 Saves the current variable value in ‘$_’ or the named
1542[4mvar[24m for later
1543 reference. Example usage:
1544 M_cmpv.units = 1 1000 1000000
1546 M_cmpv = S,., ,g:_:range:@i@+ $${_:[‐$$i]}
1547$${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh
1548 .if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}}
1550 Here ‘$_’ is used to save the result of the ‘:S’ modi‐
1552fier which is
1553 later referenced using the index values from ‘:range’.
1554 [1m:U[4m[22mnewval[0m
1556 If the variable is undefined, [4mnewval[24m is the val‐
1557ue. If the variable
1558 is defined, the existing value is returned. This is
1559another ODE
1560 make feature. It is handy for setting per‐target
1561CFLAGS for in‐
1562 stance:
1563 ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
1564 If a value is only required if the variable is unde‐
1565fined, use:
1566 ${VAR:D:Unewval}
1567 [1m:D[4m[22mnewval[0m
1569 If the variable is defined, [4mnewval[24m is the value.
1570 [1m:L [22mThe name of the variable is the value.
1572 [1m:P [22mThe path of the node which has the same name as
1574the variable is the
1575 value. If no such node exists or its path is null,
1576then the name of
1577 the variable is used. In order for this modifier to
1578work, the name
1579 (node) must at least have appeared on the rhs of a de‐
1580pendency.
1581 [1m:![4m[22mcmd[24m[1m![0m
1583 The output of running [4mcmd[24m is the value.
1584 [1m:sh [22mIf the variable is non‐empty it is run as a com‐
1586mand and the output
1587 becomes the new value.
1588 [1m::=[4m[22mstr[0m
1590 The variable is assigned the value [4mstr[24m after
1591substitution. This
1592 modifier and its variations are useful in obscure situ‐
1593ations such as
1594 wanting to set a variable when shell commands are being
1595parsed.
1596 These assignment modifiers always expand to nothing, so
1597if appearing
1598 in a rule line by themselves should be preceded with
1599something to
1600 keep [1mbmake [22mhappy.
1601 The ‘[1m::[22m’ helps avoid false matches with the AT&T
1603System V UNIX style
1604 [1m:= [22mmodifier and since substitution always occurs
1605the [1m::= [22mform is
1606 vaguely appropriate.
1607 [1m::?=[4m[22mstr[0m
1609 As for [1m::= [22mbut only if the variable does not al‐
1610ready have a value.
1611 [1m::+=[4m[22mstr[0m
1613 Append [4mstr[24m to the variable.
1614 [1m::!=[4m[22mcmd[0m
1616 Assign the output of [4mcmd[24m to the variable.
1617 [1m:[[4m[22mrange[24m[1m][0m
1619 Selects one or more words from the value, or performs
1620other opera‐
1621 tions related to the way in which the value is divided
1622into words.
1623 Ordinarily, a value is treated as a sequence of words
1625delimited by
1626 white space. Some modifiers suppress this behavior,
1627causing a value
1628 to be treated as a single word (possibly containing em‐
1629bedded white
1630 space). An empty value, or a value that consists en‐
1631tirely of white‐
1632 space, is treated as a single word. For the purposes
1633of the ‘[1m:[][22m’
1634 modifier, the words are indexed both forwards using
1635positive inte‐
1636 gers (where index 1 represents the first word), and
1637backwards using
1638 negative integers (where index ‐1 represents the last
1639word).
1640 The [4mrange[24m is subjected to variable expansion,
1642and the expanded re‐
1643 sult is then interpreted as follows:
1644 [4mindex[24m Selects a single word from the value.
1646 [4mstart[24m[1m..[4m[22mend[0m
1648 Selects all words from [4mstart[24m to
1649[4mend[24m, inclusive. For example,
1650 ‘[1m:[2..‐1][22m’ selects all words from the
1651second word to the last
1652 word. If [4mstart[24m is greater than
1653[4mend[24m, then the words are out‐
1654 put in reverse order. For example,
1655‘[1m:[‐1..1][22m’ selects all
1656 the words from last to first. If the list is
1657already or‐
1658 dered, then this effectively reverses the list,
1659but it is
1660 more efficient to use ‘[1m:Or[22m’ instead of
1661‘[1m:O:[‐1..1][22m’.
1662 [1m* [22mCauses subsequent modifiers to treat the
1664value as a single
1665 word (possibly containing embedded white space).
1666Analogous
1667 to the effect of "$*" in Bourne shell.
1668 0 Means the same as ‘[1m:[*][22m’.
1670 [1m@ [22mCauses subsequent modifiers to treat the
1672value as a sequence
1673 of words delimited by white space. Analogous to
1674the effect
1675 of "$@" in Bourne shell.
1676 [1m# [22mReturns the number of words in the value.
1678[1mINCLUDE STATEMENTS, CONDITIONALS AND FOR LOOPS[0m
1680 Makefile inclusion, conditional structures and for loops
1681reminiscent of
1682 the C programming language are provided in [1mbmake[22m.
1683All such structures
1684 are identified by a line beginning with a single dot (‘.’)
1685character.
1686 Files are included with either [1m.include
1687<[4m[22mfile[24m[1m> [22mor [1m.include "[4m[22mfile[24m[1m"[22m.
1688Vari‐
1689 ables between the angle brackets or double quotes are ex‐
1690panded to form
1691 the file name. If angle brackets are used, the included
1692makefile is ex‐
1693 pected to be in the system makefile directory. If double
1694quotes are
1695 used, the including makefile’s directory and any directories
1696specified
1697 using the [1m‐I [22moption are searched before the system
1698makefile directory.
1699 For compatibility with other versions of [1mbmake [22m‘in‐
1700clude file ...’ is also
1701 accepted.
1702 If the include statement is written as [1m.‐include [22mor
1704as [1m.sinclude [22mthen er‐
1705 rors locating and/or opening include files are ignored.
1706 If the include statement is written as [1m.dinclude [22mnot
1708only are errors lo‐
1709 cating and/or opening include files ignored, but stale de‐
1710pendencies
1711 within the included file will be ignored just like
1712[4m.MAKE.DEPENDFILE[24m.
1713 Conditional expressions are also preceded by a single dot as
1715the first
1716 character of a line. The possible conditionals are as fol‐
1717lows:
1718 [1m.error [4m[22mmessage[0m
1720 The message is printed along with the name of the
1721makefile and
1722 line number, then [1mbmake [22mwill exit immediate‐
1723ly.
1724 [1m.export [4m[22mvariable[24m [4m...[0m
1726 Export the specified global variable. If no vari‐
1727able list is
1728 provided, all globals are exported except for inter‐
1729nal variables
1730 (those that start with ‘.’). This is not affected
1731by the [1m‐X[0m
1732 flag, so should be used with caution. For compati‐
1733bility with
1734 other [1mbmake [22mprograms ‘export variable=value’
1735is also accepted.
1736 Appending a variable name to [4m.MAKE.EXPORTED[24m
1738is equivalent to ex‐
1739 porting a variable.
1740 [1m.export‐env [4m[22mvariable[24m [4m...[0m
1742 The same as ‘.export’, except that the variable is
1743not appended
1744 to [4m.MAKE.EXPORTED[24m. This allows exporting a
1745value to the environ‐
1746 ment which is different from that used by [1mbmake
1747[22minternally.
1748 [1m.export‐literal [4m[22mvariable[24m [4m...[0m
1750 The same as ‘.export‐env’, except that variables in
1751the value are
1752 not expanded.
1753 [1m.info [4m[22mmessage[0m
1755 The message is printed along with the name of the
1756makefile and
1757 line number.
1758 [1m.undef [4m[22mvariable[24m [4m...[0m
1760 Un‐define the specified global variables. Only
1761global variables
1762 can be un‐defined.
1763 [1m.unexport [4m[22mvariable[24m [4m...[0m
1765 The opposite of ‘.export’. The specified global
1766[4mvariable[24m will be
1767 removed from [4m.MAKE.EXPORTED[24m. If no variable
1768list is provided,
1769 all globals are unexported, and [4m.MAKE.EXPORT‐
1770ED[24m deleted.
1771 [1m.unexport‐env[0m
1773 Unexport all globals previously exported and clear
1774the environ‐
1775 ment inherited from the parent. This operation will
1776cause a mem‐
1777 ory leak of the original environment, so should be
1778used spar‐
1779 ingly. Testing for [4m.MAKE.LEVEL[24m being 0,
1780would make sense. Also
1781 note that any variables which originated in the par‐
1782ent environ‐
1783 ment should be explicitly preserved if desired. For
1784example:
1785 .if ${.MAKE.LEVEL} == 0
1787 PATH := ${PATH}
1788 .unexport‐env
1789 .export PATH
1790 .endif
1791 Would result in an environment containing only
1793‘PATH’, which is
1794 the minimal useful environment. Actually
1795‘.MAKE.LEVEL’ will also
1796 be pushed into the new environment.
1797 [1m.warning [4m[22mmessage[0m
1799 The message prefixed by ‘[4mwarning:[24m’ is printed
1800along with the name
1801 of the makefile and line number.
1802 [1m.if [22m[!][4mexpression[24m [[4moperator[24m [4mexpres‐
1804sion[24m [4m...[24m]
1805 Test the value of an expression.
1806 [1m.ifdef [22m[!][4mvariable[24m [[4moperator[24m [4mvari‐
1808able[24m [4m...[24m]
1809 Test the value of a variable.
1810 [1m.ifndef [22m[!][4mvariable[24m [[4moperator[24m [4mvari‐
1812able[24m [4m...[24m]
1813 Test the value of a variable.
1814 [1m.ifmake [22m[!][4mtarget[24m [[4moperator[24m [4mtar‐
1816get[24m [4m...[24m]
1817 Test the target being built.
1818 [1m.ifnmake [22m[!] [4mtarget[24m [[4moperator[24m [4mtar‐
1820get[24m [4m...[24m]
1821 Test the target being built.
1822 [1m.else [22mReverse the sense of the last conditional.
1824 [1m.elif [22m[!] [4mexpression[24m [[4moperator[24m [4mex‐
1826pression[24m [4m...[24m]
1827 A combination of ‘[1m.else[22m’ followed by
1828‘[1m.if[22m’.
1829 [1m.elifdef [22m[!][4mvariable[24m [[4moperator[24m [4mvari‐
1831able[24m [4m...[24m]
1832 A combination of ‘[1m.else[22m’ followed by
1833‘[1m.ifdef[22m’.
1834 [1m.elifndef [22m[!][4mvariable[24m [[4moperator[24m
1836[4mvariable[24m [4m...[24m]
1837 A combination of ‘[1m.else[22m’ followed by
1838‘[1m.ifndef[22m’.
1839 [1m.elifmake [22m[!][4mtarget[24m [[4moperator[24m [4mtar‐
1841get[24m [4m...[24m]
1842 A combination of ‘[1m.else[22m’ followed by ‘[1m.if‐
1843make[22m’.
1844 [1m.elifnmake [22m[!][4mtarget[24m [[4moperator[24m [4mtar‐
1846get[24m [4m...[24m]
1847 A combination of ‘[1m.else[22m’ followed by
1848‘[1m.ifnmake[22m’.
1849 [1m.endif [22mEnd the body of the conditional.
1851 The [4moperator[24m may be any one of the following:
1853 [1m|| [22mLogical OR.
1855 [1m&& [22mLogical AND; of higher precedence than “||”.
1857 As in C, [1mbmake [22mwill only evaluate a conditional as
1859far as is necessary to
1860 determine its value. Parentheses may be used to change the
1861order of
1862 evaluation. The boolean operator ‘[1m![22m’ may be used to
1863logically negate an
1864 entire conditional. It is of higher precedence than
1865‘[1m&&[22m’.
1866 The value of [4mexpression[24m may be any of the following:
1868 [1mdefined [22mTakes a variable name as an argument and
1870evaluates to true if
1871 the variable has been defined.
1872 [1mmake [22mTakes a target name as an argument and eval‐
1874uates to true if the
1875 target was specified as part of [1mbmake[22m’s com‐
1876mand line or was de‐
1877 clared the default target (either implicitly or ex‐
1878plicitly, see
1879 [4m.MAIN[24m) before the line containing the condi‐
1880tional.
1881 [1mempty [22mTakes a variable, with possible modifiers,
1883and evaluates to true
1884 if the expansion of the variable would result in an
1885empty
1886 string.
1887 [1mexists [22mTakes a file name as an argument and evalu‐
1889ates to true if the
1890 file exists. The file is searched for on the sys‐
1891tem search path
1892 (see [4m.PATH[24m).
1893 [1mtarget [22mTakes a target name as an argument and eval‐
1895uates to true if the
1896 target has been defined.
1897 [1mcommands[0m
1899 Takes a target name as an argument and evaluates to
1900true if the
1901 target has been defined and has commands associated
1902with it.
1903 [4mExpression[24m may also be an arithmetic or string com‐
1905parison. Variable ex‐
1906 pansion is performed on both sides of the comparison, after
1907which the nu‐
1908 merical values are compared. A value is interpreted as
1909hexadecimal if it
1910 is preceded by 0x, otherwise it is decimal; octal numbers
1911are not sup‐
1912 ported. The standard C relational operators are all sup‐
1913ported. If after
1914 variable expansion, either the left or right hand side of a
1915‘[1m==[22m’ or ‘[1m!=[22m’
1916 operator is not a numerical value, then string comparison is
1917performed
1918 between the expanded variables. If no relational operator
1919is given, it
1920 is assumed that the expanded variable is being compared
1921against 0, or an
1922 empty string in the case of a string comparison.
1923 When [1mbmake [22mis evaluating one of these conditional ex‐
1925pressions, and it en‐
1926 counters a (white‐space separated) word it doesn’t recog‐
1927nize, either the
1928 “make” or “defined” expression is applied to it, depending
1929on the form of
1930 the conditional. If the form is ‘[1m.ifdef[22m’, ‘[1m.ifn‐
1931def[22m’, or ‘[1m.if[22m’ the
1932 “defined” expression is applied. Similarly, if the form is
1933‘[1m.ifmake[22m’ or
1934 ‘[1m.ifnmake[22m’, the “make” expression is applied.
1935 If the conditional evaluates to true the parsing of the
1937makefile contin‐
1938 ues as before. If it evaluates to false, the following
1939lines are
1940 skipped. In both cases this continues until a
1941‘[1m.else[22m’ or ‘[1m.endif[22m’ is
1942 found.
1943 For loops are typically used to apply a set of rules to a
1945list of files.
1946 The syntax of a for loop is:
1947 [1m.for [4m[22mvariable[24m [[4mvariable[24m [4m...[24m]
1949[1min [4m[22mexpression[0m
1950 ⟨make‐lines⟩
1951 [1m.endfor[0m
1952 After the for [1mexpression [22mis evaluated, it is split
1954into words. On each
1955 iteration of the loop, one word is taken and assigned to
1956each [1mvariable[22m,
1957 in order, and these [1mvariables [22mare substituted into
1958the [1mmake‐lines [22minside
1959 the body of the for loop. The number of words must come out
1960even; that
1961 is, if there are three iteration variables, the number of
1962words provided
1963 must be a multiple of three.
1964[1mCOMMENTS[0m
1966 Comments begin with a hash (‘#’) character, anywhere but in
1967a shell com‐
1968 mand line, and continue to the end of an unescaped new line.
1969[1mSPECIAL SOURCES (ATTRIBUTES)[0m
1971 [1m.EXEC [22mTarget is never out of date, but always ex‐
1972ecute commands any‐
1973 way.
1974 [1m.IGNORE [22mIgnore any errors from the commands associ‐
1976ated with this tar‐
1977 get, exactly as if they all were preceded by a
1978dash (‘‐’).
1979 [1m.MADE [22mMark all sources of this target as being
1981up‐to‐date.
1982 [1m.MAKE [22mExecute the commands associated with this
1984target even if the [1m‐n[0m
1985 or [1m‐t [22moptions were specified. Normally
1986used to mark recursive
1987 [1mbmake[22ms.
1988 [1m.META [22mCreate a meta file for the target, even if
1990it is flagged as
1991 [1m.PHONY[22m, [1m.MAKE[22m, or [1m.SPECIAL[22m.
1992Usage in conjunction with [1m.MAKE [22mis
1993 the most likely case. In "meta" mode, the target
1994is out‐of‐
1995 date if the meta file is missing.
1996 [1m.NOMETA [22mDo not create a meta file for the target.
1998Meta files are also
1999 not created for [1m.PHONY[22m, [1m.MAKE[22m, or
2000[1m.SPECIAL [22mtargets.
2001 [1m.NOMETA_CMP[0m
2003 Ignore differences in commands when deciding if
2004target is out
2005 of date. This is useful if the command contains a
2006value which
2007 always changes. If the number of commands change,
2008though, the
2009 target will still be out of date. The same effect
2010applies to
2011 any command line that uses the variable [4m.OO‐
2012DATE[24m, which can be
2013 used for that purpose even when not otherwise
2014needed or de‐
2015 sired:
2016 skip‐compare‐for‐some:
2019 @echo this will be compared
2020 @echo this will not ${.OO‐
2021DATE:M.NOMETA_CMP}
2022 @echo this will also be compared
2023 The [1m:M [22mpattern suppresses any expansion of
2025the unwanted vari‐
2026 able.
2027 [1m.NOPATH [22mDo not search for the target in the direc‐
2029tories specified by
2030 [1m.PATH[22m.
2031 [1m.NOTMAIN [22mNormally [1mbmake [22mselects the first
2033target it encounters as the
2034 default target to be built if no target was speci‐
2035fied. This
2036 source prevents this target from being selected.
2037 [1m.OPTIONAL[0m
2039 If a target is marked with this attribute and
2040[1mbmake [22mcan’t fig‐
2041 ure out how to create it, it will ignore this fact
2042and assume
2043 the file isn’t needed or already exists.
2044 [1m.PHONY [22mThe target does not correspond to an actual
2046file; it is always
2047 considered to be out of date, and will not be cre‐
2048ated with the
2049 [1m‐t [22moption. Suffix‐transformation rules are
2050not applied to
2051 [1m.PHONY [22mtargets.
2052 [1m.PRECIOUS[0m
2054 When [1mbmake [22mis interrupted, it normally re‐
2055moves any partially
2056 made targets. This source prevents the target
2057from being re‐
2058 moved.
2059 [1m.RECURSIVE[0m
2061 Synonym for [1m.MAKE[22m.
2062 [1m.SILENT [22mDo not echo any of the commands associated
2064with this target,
2065 exactly as if they all were preceded by an at sign
2066(‘@’).
2067 [1m.USE [22mTurn the target into [1mbmake[22m’s version
2069of a macro. When the tar‐
2070 get is used as a source for another target, the
2071other target
2072 acquires the commands, sources, and attributes
2073(except for
2074 [1m.USE[22m) of the source. If the target already
2075has commands, the
2076 [1m.USE [22mtarget’s commands are appended to
2077them.
2078 [1m.USEBEFORE[0m
2080 Exactly like [1m.USE[22m, but prepend the [1m.USE‐
2081BEFORE [22mtarget commands
2082 to the target.
2083 [1m.WAIT [22mIf [1m.WAIT [22mappears in a dependency
2085line, the sources that precede
2086 it are made before the sources that succeed it in
2087the line.
2088 Since the dependents of files are not made until
2089the file it‐
2090 self could be made, this also stops the dependents
2091being built
2092 unless they are needed for another branch of the
2093dependency
2094 tree. So given:
2095 x: a .WAIT b
2097 echo x
2098 a:
2099 echo a
2100 b: b1
2101 echo b
2102 b1:
2103 echo b1
2104 the output is always ‘a’, ‘b1’, ‘b’, ‘x’.
2106 The ordering imposed by [1m.WAIT [22mis only rele‐
2107vant for parallel
2108 makes.
2109[1mSPECIAL TARGETS[0m
2111 Special targets may not be included with other targets, i.e.
2112they must be
2113 the only target specified.
2114 [1m.BEGIN [22mAny command lines attached to this target
2116are executed before
2117 anything else is done.
2118 [1m.DEFAULT[0m
2120 This is sort of a [1m.USE [22mrule for any target
2121(that was used only
2122 as a source) that [1mbmake [22mcan’t figure out any
2123other way to cre‐
2124 ate. Only the shell script is used. The [1m.IMP‐
2125SRC [22mvariable of a
2126 target that inherits [1m.DEFAULT[22m’s commands is
2127set to the target’s
2128 own name.
2129 [1m.DELETE_ON_ERROR[0m
2131 If this target is present in the makefile, it glob‐
2132ally causes
2133 make to delete targets whose commands fail. (By
2134default, only
2135 targets whose commands are interrupted during exe‐
2136cution are
2137 deleted. This is the historical behavior.) This
2138setting can be
2139 used to help prevent half‐finished or malformed
2140targets from be‐
2141 ing left around and corrupting future rebuilds.
2142 [1m.END [22mAny command lines attached to this target
2144are executed after ev‐
2145 erything else is done.
2146 [1m.ERROR [22mAny command lines attached to this target
2148are executed when an‐
2149 other target fails. The [1m.ERROR_TARGET [22mvari‐
2150able is set to the
2151 target that failed. See also
2152[1mMAKE_PRINT_VAR_ON_ERROR[22m.
2153 [1m.IGNORE [22mMark each of the sources with the [1m.IGNORE
2155[22mattribute. If no
2156 sources are specified, this is the equivalent of
2157specifying the
2158 [1m‐i [22moption.
2159 [1m.INTERRUPT[0m
2161 If [1mbmake [22mis interrupted, the commands for
2162this target will be
2163 executed.
2164 [1m.MAIN [22mIf no target is specified when [1mbmake
2166[22mis invoked, this target
2167 will be built.
2168 [1m.MAKEFLAGS[0m
2170 This target provides a way to specify flags for
2171[1mbmake [22mwhen the
2172 makefile is used. The flags are as if typed to the
2173shell,
2174 though the [1m‐f [22moption will have no effect.
2175 [1m.NOPATH [22mApply the [1m.NOPATH [22mattribute to any
2177specified sources.
2178 [1m.NOTPARALLEL[0m
2180 Disable parallel mode.
2181 [1m.NO_PARALLEL[0m
2183 Synonym for [1m.NOTPARALLEL[22m, for compatibility
2184with other pmake
2185 variants.
2186 [1m.OBJDIR [22mThe source is a new value for ‘[4m.OB‐
2188JDIR[24m’. If it exists, [1mbmake[0m
2189 will chdir(2) to it and update the value of
2190‘[4m.OBJDIR[24m’.
2191 [1m.ORDER [22mIn parallel mode, the named targets are made
2193in sequence. This
2194 ordering does not add targets to the list of tar‐
2195gets to be made.
2196 Since the dependents of a target do not get built
2198until the tar‐
2199 get itself could be built, unless ‘a’ is built by
2200another part
2201 of the dependency graph, the following is a depen‐
2202dency loop:
2203 .ORDER: b a
2205 b: a
2206 [1m.PATH [22mThe sources are directories which are to be
2208searched for files
2209 not found in the current directory. If no sources
2210are speci‐
2211 fied, any previously specified directories are
2212deleted. If the
2213 source is the special [1m.DOTLAST [22mtarget, then
2214the current working
2215 directory is searched last.
2216 [1m.PATH.[4m[22msuffix[0m
2218 Like [1m.PATH [22mbut applies only to files with a
2219particular suffix.
2220 The suffix must have been previously declared with
2221[1m.SUFFIXES[22m.
2222 [1m.PHONY [22mApply the [1m.PHONY [22mattribute to any
2224specified sources.
2225 [1m.POSIX [22mIf this is the first non‐comment line in the
2227main makefile, the
2228 variable [4m%POSIX[24m is set to the value ‘1003.2’
2229and the makefile
2230 ‘<posix.mk>’ is included if it exists, to provide
2231POSIX‐compati‐
2232 ble default rules. If [1mbmake [22mis run with the
2233[1m‐r [22mflag, then only
2234 ‘posix.mk’ will contribute to the default rules.
2235 [1m.PRECIOUS[0m
2237 Apply the [1m.PRECIOUS [22mattribute to any speci‐
2238fied sources. If no
2239 sources are specified, the [1m.PRECIOUS [22mat‐
2240tribute is applied to ev‐
2241 ery target in the file.
2242 [1m.SHELL [22mSets the shell that [1mbmake [22mwill use to
2244execute commands. The
2245 sources are a set of [4mfield=value[24m pairs.
2246 [4mname[24m This is the minimal specifica‐
2248tion, used to select
2249 one of the built‐in shell specs;
2250[4msh[24m, [4mksh[24m, and [4mcsh[24m.
2251 [4mpath[24m Specifies the path to the shell.
2253 [4mhasErrCtl[24m Indicates whether the shell sup‐
2255ports exit on error.
2256 [4mcheck[24m The command to turn on error
2258checking.
2259 [4mignore[24m The command to disable error
2261checking.
2262 [4mecho[24m The command to turn on echoing
2264of commands executed.
2265 [4mquiet[24m The command to turn off echoing
2267of commands exe‐
2268 cuted.
2269 [4mfilter[24m The output to filter after issu‐
2271ing the [4mquiet[24m com‐
2272 mand. It is typically identical to
2273[4mquiet[24m.
2274 [4merrFlag[24m The flag to pass the shell to
2276enable error checking.
2277 [4mechoFlag[24m The flag to pass the shell to
2279enable command echo‐
2280 ing.
2281 [4mnewline[24m The string literal to pass the
2283shell that results in
2284 a single newline character when used
2285outside of any
2286 quoting characters.
2287 Example:
2288 .SHELL: name=ksh path=/bin/ksh hasErrCtl=true
2290check="set ‐e" ignore="set +e" echo="set
2291‐v" quiet="set +v" filter="set +v"
2292echoFlag=v errFlag=e newline="’0"
2293 [1m.SILENT [22mApply the [1m.SILENT [22mattribute to any
2295specified sources. If no
2296 sources are specified, the [1m.SILENT [22mattribute
2297is applied to every
2298 command in the file.
2299 [1m.STALE [22mThis target gets run when a dependency file
2301contains stale en‐
2302 tries, having [4m.ALLSRC[24m set to the name of
2303that dependency file.
2304 [1m.SUFFIXES[0m
2306 Each source specifies a suffix to [1mbmake[22m. If
2307no sources are
2308 specified, any previously specified suffixes are
2309deleted. It
2310 allows the creation of suffix‐transformation rules.
2311 Example:
2313 .SUFFIXES: .o
2315 .c.o:
2316 cc ‐o ${.TARGET} ‐c ${.IMPSRC}
2317[1mENVIRONMENT[0m
2319 [1mbmake [22muses the following environment variables, if
2320they exist: MACHINE,
2321 MACHINE_ARCH, MAKE, MAKEFLAGS, MAKEOBJDIR, MAKEOBJDIRPREFIX,
2322MAKESYSPATH,
2323 PWD, and TMPDIR.
2324 MAKEOBJDIRPREFIX and MAKEOBJDIR may only be set in the envi‐
2326ronment or on
2327 the command line to [1mbmake [22mand not as makefile vari‐
2328ables; see the descrip‐
2329 tion of ‘[4m.OBJDIR[24m’ for more details.
2330[1mFILES[0m
2332 .depend list of dependencies
2333 Makefile list of dependencies
2334 makefile list of dependencies
2335 sys.mk system makefile
2336 /usr/share/mk system makefile directory
2337[1mCOMPATIBILITY[0m
2339 The basic make syntax is compatible between different ver‐
2340sions of make;
2341 however the special variables, variable modifiers and condi‐
2342tionals are
2343 not.
2344 [1mOlder versions[0m
2346 An incomplete list of changes in older versions of [1mb‐
2347make[22m:
2348 The way that .for loop variables are substituted changed af‐
2350ter NetBSD 5.0
2351 so that they still appear to be variable expansions. In
2352particular this
2353 stops them being treated as syntax, and removes some obscure
2354problems us‐
2355 ing them in .if statements.
2356 The way that parallel makes are scheduled changed in NetBSD
23584.0 so that
2359 .ORDER and .WAIT apply recursively to the dependent nodes.
2360The algo‐
2361 rithms used may change again in the future.
2362 [1mOther make dialects[0m
2364 Other make dialects (GNU make, SVR4 make, POSIX make, etc.)
2365do not sup‐
2366 port most of the features of [1mbmake [22mas described in
2367this manual. Most no‐
2368 tably:
2369 [1m• [22mThe [1m.WAIT [22mand [1m.ORDER [22mdeclara‐
2371tions and most functionality per‐
2372 taining to parallelization. (GNU make supports
2373parallelization
2374 but lacks these features needed to control it ef‐
2375fectively.)
2376 [1m• [22mDirectives, including for loops and condi‐
2378tionals and most of
2379 the forms of include files. (GNU make has its own
2380incompatible
2381 and less powerful syntax for conditionals.)
2382 [1m• [22mAll built‐in variables that begin with a
2384dot.
2385 [1m• [22mMost of the special sources and targets
2387that begin with a dot,
2388 with the notable exception of [1m.PHONY[22m,
2389[1m.PRECIOUS[22m, and [1m.SUFFIXES[22m.
2390 [1m• [22mVariable modifiers, except for the
2392 :old=new
2393 string substitution, which does not portably sup‐
2394port globbing
2395 with ‘%’ and historically only works on declared
2396suffixes.
2397 [1m• [22mThe [1m$> [22mvariable even in its short
2399form; most makes support this
2400 functionality but its name varies.
2401 Some features are somewhat more portable, such as assignment
2403with [1m+=[22m, [1m?=[22m,
2404 and [1m!=[22m. The [1m.PATH [22mfunctionality is based on
2405an older feature [1mVPATH [22mfound
2406 in GNU make and many versions of SVR4 make; however, histor‐
2407ically its be‐
2408 havior is too ill‐defined (and too buggy) to rely upon.
2409 The [1m$@ [22mand [1m$< [22mvariables are more or less uni‐
2411versally portable, as is the
2412 [1m$(MAKE) [22mvariable. Basic use of suffix rules (for
2413files only in the cur‐
2414 rent directory, not trying to chain transformations togeth‐
2415er, etc.) is
2416 also reasonably portable.
2417[1mSEE ALSO[0m
2419 mkdep(1)
2420[1mHISTORY[0m
2422 [1mbmake [22mis derived from NetBSD make(1). It uses auto‐
2423conf to facilitate
2424 portability to other platforms.
2425 A make command appeared in Version 7 AT&T UNIX. This make
2427implementation
2428 is based on Adam De Boor’s pmake program which was written
2429for Sprite at
2430 Berkeley. It was designed to be a parallel distributed make
2431running jobs
2432 on different machines using a daemon called “customs”.
2433 Historically the target/dependency “FRC” has been used to
2435FoRCe rebuild‐
2436 ing (since the target/dependency does not exist... unless
2437someone creates
2438 an “FRC” file).
2439[1mBUGS[0m
2441 The make syntax is difficult to parse without actually act‐
2442ing on the
2443 data. For instance, finding the end of a variable’s use
2444should involve
2445 scanning each of the modifiers, using the correct terminator
2446for each
2447 field. In many places make just counts {} and () in order
2448to find the
2449 end of a variable expansion.
2450 There is no way of escaping a space character in a filename.
2452FreeBSD 13.0 May 7, 2022
2454FreeBSD 13.0
2455