xref: /dragonfly/contrib/bmake/bmake.cat1 (revision 0ca59c34)
1MAKE(1)                 NetBSD General Commands Manual                 MAKE(1)
2
3NNAAMMEE
4     bbmmaakkee -- maintain program dependencies
5
6SSYYNNOOPPSSIISS
7     bbmmaakkee [--BBeeiikkNNnnqqrrssttWWwwXX] [--CC _d_i_r_e_c_t_o_r_y] [--DD _v_a_r_i_a_b_l_e] [--dd _f_l_a_g_s]
8           [--ff _m_a_k_e_f_i_l_e] [--II _d_i_r_e_c_t_o_r_y] [--JJ _p_r_i_v_a_t_e] [--jj _m_a_x___j_o_b_s]
9           [--mm _d_i_r_e_c_t_o_r_y] [--TT _f_i_l_e] [--VV _v_a_r_i_a_b_l_e] [_v_a_r_i_a_b_l_e_=_v_a_l_u_e]
10           [_t_a_r_g_e_t _._._.]
11
12DDEESSCCRRIIPPTTIIOONN
13     bbmmaakkee is a program designed to simplify the maintenance of other pro-
14     grams.  Its input is a list of specifications as to the files upon which
15     programs and other files depend.  If no --ff _m_a_k_e_f_i_l_e makefile option is
16     given, bbmmaakkee will try to open `_m_a_k_e_f_i_l_e' then `_M_a_k_e_f_i_l_e' in order to find
17     the specifications.  If the file `_._d_e_p_e_n_d' exists, it is read (see
18     mkdep(1)).
19
20     This manual page is intended as a reference document only.  For a more
21     thorough description of bbmmaakkee and makefiles, please refer to _P_M_a_k_e _- _A
22     _T_u_t_o_r_i_a_l.
23
24     bbmmaakkee will prepend the contents of the _M_A_K_E_F_L_A_G_S environment variable to
25     the command line arguments before parsing them.
26
27     The options are as follows:
28
29     --BB      Try to be backwards compatible by executing a single shell per
30             command and by executing the commands to make the sources of a
31             dependency line in sequence.
32
33     --CC _d_i_r_e_c_t_o_r_y
34             Change to _d_i_r_e_c_t_o_r_y before reading the makefiles or doing any-
35             thing else.  If multiple --CC options are specified, each is inter-
36             preted relative to the previous one: --CC _/ --CC _e_t_c is equivalent to
37             --CC _/_e_t_c.
38
39     --DD _v_a_r_i_a_b_l_e
40             Define _v_a_r_i_a_b_l_e to be 1, in the global context.
41
42     --dd _[_-_]_f_l_a_g_s
43             Turn on debugging, and specify which portions of bbmmaakkee are to
44             print debugging information.  Unless the flags are preceded by
45             `-' they are added to the _M_A_K_E_F_L_A_G_S environment variable and will
46             be processed by any child make processes.  By default, debugging
47             information is printed to standard error, but this can be changed
48             using the _F debugging flag.  The debugging output is always
49             unbuffered; in addition, if debugging is enabled but debugging
50             output is not directed to standard output, then the standard out-
51             put is line buffered.  _F_l_a_g_s is one or more of the following:
52
53             _A       Print all possible debugging information; equivalent to
54                     specifying all of the debugging flags.
55
56             _a       Print debugging information about archive searching and
57                     caching.
58
59             _C       Print debugging information about current working direc-
60                     tory.
61
62             _c       Print debugging information about conditional evaluation.
63
64             _d       Print debugging information about directory searching and
65                     caching.
66
67             _e       Print debugging information about failed commands and
68                     targets.
69
70             _F[++]_f_i_l_e_n_a_m_e
71                     Specify where debugging output is written.  This must be
72                     the last flag, because it consumes the remainder of the
73                     argument.  If the character immediately after the `F'
74                     flag is `+', then the file will be opened in append mode;
75                     otherwise the file will be overwritten.  If the file name
76                     is `stdout' or `stderr' then debugging output will be
77                     written to the standard output or standard error output
78                     file descriptors respectively (and the `+' option has no
79                     effect).  Otherwise, the output will be written to the
80                     named file.  If the file name ends `.%d' then the `%d' is
81                     replaced by the pid.
82
83             _f       Print debugging information about loop evaluation.
84
85             _g_1      Print the input graph before making anything.
86
87             _g_2      Print the input graph after making everything, or before
88                     exiting on error.
89
90             _g_3      Print the input graph before exiting on error.
91
92             _j       Print debugging information about running multiple
93                     shells.
94
95             _l       Print commands in Makefiles regardless of whether or not
96                     they are prefixed by `@' or other "quiet" flags.  Also
97                     known as "loud" behavior.
98
99             _M       Print debugging information about "meta" mode decisions
100                     about targets.
101
102             _m       Print debugging information about making targets, includ-
103                     ing modification dates.
104
105             _n       Don't delete the temporary command scripts created when
106                     running commands.  These temporary scripts are created in
107                     the directory referred to by the TMPDIR environment vari-
108                     able, or in _/_t_m_p if TMPDIR is unset or set to the empty
109                     string.  The temporary scripts are created by mkstemp(3),
110                     and have names of the form _m_a_k_e_X_X_X_X_X_X.  _N_O_T_E: This can
111                     create many files in TMPDIR or _/_t_m_p, so use with care.
112
113             _p       Print debugging information about makefile parsing.
114
115             _s       Print debugging information about suffix-transformation
116                     rules.
117
118             _t       Print debugging information about target list mainte-
119                     nance.
120
121             _V       Force the --VV option to print raw values of variables.
122
123             _v       Print debugging information about variable assignment.
124
125             _w       Print entering and leaving directory messages, pre and
126                     post processing.
127
128             _x       Run shell commands with --xx so the actual commands are
129                     printed as they are executed.
130
131     --ee      Specify that environment variables override macro assignments
132             within makefiles.
133
134     --ff _m_a_k_e_f_i_l_e
135             Specify a makefile to read instead of the default `_m_a_k_e_f_i_l_e'.  If
136             _m_a_k_e_f_i_l_e is `--', standard input is read.  Multiple makefiles may
137             be specified, and are read in the order specified.
138
139     --II _d_i_r_e_c_t_o_r_y
140             Specify a directory in which to search for makefiles and included
141             makefiles.  The system makefile directory (or directories, see
142             the --mm option) is automatically included as part of this list.
143
144     --ii      Ignore non-zero exit of shell commands in the makefile.  Equiva-
145             lent to specifying `--' before each command line in the makefile.
146
147     --JJ _p_r_i_v_a_t_e
148             This option should _n_o_t be specified by the user.
149
150             When the _j option is in use in a recursive build, this option is
151             passed by a make to child makes to allow all the make processes
152             in the build to cooperate to avoid overloading the system.
153
154     --jj _m_a_x___j_o_b_s
155             Specify the maximum number of jobs that bbmmaakkee may have running at
156             any one time.  The value is saved in _._M_A_K_E_._J_O_B_S.  Turns compati-
157             bility mode off, unless the _B flag is also specified.  When com-
158             patibility mode is off, all commands associated with a target are
159             executed in a single shell invocation as opposed to the tradi-
160             tional one shell invocation per line.  This can break traditional
161             scripts which change directories on each command invocation and
162             then expect to start with a fresh environment on the next line.
163             It is more efficient to correct the scripts rather than turn
164             backwards compatibility on.
165
166     --kk      Continue processing after errors are encountered, but only on
167             those targets that do not depend on the target whose creation
168             caused the error.
169
170     --mm _d_i_r_e_c_t_o_r_y
171             Specify a directory in which to search for sys.mk and makefiles
172             included via the <_f_i_l_e>-style include statement.  The --mm option
173             can be used multiple times to form a search path.  This path will
174             override the default system include path: /usr/share/mk.  Fur-
175             thermore the system include path will be appended to the search
176             path used for "_f_i_l_e"-style include statements (see the --II
177             option).
178
179             If a file or directory name in the --mm argument (or the
180             MAKESYSPATH environment variable) starts with the string ".../"
181             then bbmmaakkee will search for the specified file or directory named
182             in the remaining part of the argument string.  The search starts
183             with the current directory of the Makefile and then works upward
184             towards the root of the filesystem.  If the search is successful,
185             then the resulting directory replaces the ".../" specification in
186             the --mm argument.  If used, this feature allows bbmmaakkee to easily
187             search in the current source tree for customized sys.mk files
188             (e.g., by using ".../mk/sys.mk" as an argument).
189
190     --nn      Display the commands that would have been executed, but do not
191             actually execute them unless the target depends on the .MAKE spe-
192             cial source (see below).
193
194     --NN      Display the commands which would have been executed, but do not
195             actually execute any of them; useful for debugging top-level
196             makefiles without descending into subdirectories.
197
198     --qq      Do not execute any commands, but exit 0 if the specified targets
199             are up-to-date and 1, otherwise.
200
201     --rr      Do not use the built-in rules specified in the system makefile.
202
203     --ss      Do not echo any commands as they are executed.  Equivalent to
204             specifying `@@' before each command line in the makefile.
205
206     --TT _t_r_a_c_e_f_i_l_e
207             When used with the --jj flag, append a trace record to _t_r_a_c_e_f_i_l_e
208             for each job started and completed.
209
210     --tt      Rather than re-building a target as specified in the makefile,
211             create it or update its modification time to make it appear up-
212             to-date.
213
214     --VV _v_a_r_i_a_b_l_e
215             Print bbmmaakkee's idea of the value of _v_a_r_i_a_b_l_e, in the global con-
216             text.  Do not build any targets.  Multiple instances of this
217             option may be specified; the variables will be printed one per
218             line, with a blank line for each null or undefined variable.  If
219             _v_a_r_i_a_b_l_e contains a `$' then the value will be expanded before
220             printing.
221
222     --WW      Treat any warnings during makefile parsing as errors.
223
224     --XX      Don't export variables passed on the command line to the environ-
225             ment individually.  Variables passed on the command line are
226             still exported via the _M_A_K_E_F_L_A_G_S environment variable.  This
227             option may be useful on systems which have a small limit on the
228             size of command arguments.
229
230     _v_a_r_i_a_b_l_e_=_v_a_l_u_e
231             Set the value of the variable _v_a_r_i_a_b_l_e to _v_a_l_u_e.  Normally, all
232             values passed on the command line are also exported to sub-makes
233             in the environment.  The --XX flag disables this behavior.  Vari-
234             able assignments should follow options for POSIX compatibility
235             but no ordering is enforced.
236
237     There are seven different types of lines in a makefile: file dependency
238     specifications, shell commands, variable assignments, include statements,
239     conditional directives, for loops, and comments.
240
241     In general, lines may be continued from one line to the next by ending
242     them with a backslash (`\').  The trailing newline character and initial
243     whitespace on the following line are compressed into a single space.
244
245FFIILLEE DDEEPPEENNDDEENNCCYY SSPPEECCIIFFIICCAATTIIOONNSS
246     Dependency lines consist of one or more targets, an operator, and zero or
247     more sources.  This creates a relationship where the targets ``depend''
248     on the sources and are usually created from them.  The exact relationship
249     between the target and the source is determined by the operator that sep-
250     arates them.  The three operators are as follows:
251
252     ::     A target is considered out-of-date if its modification time is less
253           than those of any of its sources.  Sources for a target accumulate
254           over dependency lines when this operator is used.  The target is
255           removed if bbmmaakkee is interrupted.
256
257     !!     Targets are always re-created, but not until all sources have been
258           examined and re-created as necessary.  Sources for a target accumu-
259           late over dependency lines when this operator is used.  The target
260           is removed if bbmmaakkee is interrupted.
261
262     ::::    If no sources are specified, the target is always re-created.  Oth-
263           erwise, a target is considered out-of-date if any of its sources
264           has been modified more recently than the target.  Sources for a
265           target do not accumulate over dependency lines when this operator
266           is used.  The target will not be removed if bbmmaakkee is interrupted.
267
268     Targets and sources may contain the shell wildcard values `?', `*', `[]',
269     and `{}'.  The values `?', `*', and `[]' may only be used as part of the
270     final component of the target or source, and must be used to describe
271     existing files.  The value `{}' need not necessarily be used to describe
272     existing files.  Expansion is in directory order, not alphabetically as
273     done in the shell.
274
275SSHHEELLLL CCOOMMMMAANNDDSS
276     Each target may have associated with it a series of shell commands, nor-
277     mally used to create the target.  Each of the commands in this script
278     _m_u_s_t be preceded by a tab.  While any target may appear on a dependency
279     line, only one of these dependencies may be followed by a creation
280     script, unless the `::::' operator is used.
281
282     If the first characters of the command line are any combination of `@@',
283     `++', or `--', the command is treated specially.  A `@@' causes the command
284     not to be echoed before it is executed.  A `++' causes the command to be
285     executed even when --nn is given.  This is similar to the effect of the
286     .MAKE special source, except that the effect can be limited to a single
287     line of a script.  A `--' causes any non-zero exit status of the command
288     line to be ignored.
289
290     When bbmmaakkee is run in jobs mode with --jj _m_a_x___j_o_b_s, the entire script for
291     the target is fed to a single instance of the shell.
292
293     In compatibility (non-jobs) mode, each command is run in a separate
294     process.  If the command contains any shell meta characters
295     (`#=|^(){};&<>*?[]:$`\\n') it will be passed to the shell, otherwise
296     bbmmaakkee will attempt direct execution.
297
298     Since bbmmaakkee will chdir(2) to `_._O_B_J_D_I_R' before executing any targets, each
299     child process starts with that as its current working directory.
300
301     Makefiles should be written so that the mode of bbmmaakkee operation does not
302     change their behavior.  For example, any command which needs to use
303     ``cd'' or ``chdir'', without side-effect should be put in parenthesis:
304
305
306           avoid-chdir-side-effects:
307                   @echo Building $@ in `pwd`
308                   @(cd ${.CURDIR} && ${.MAKE} $@)
309                   @echo Back in `pwd`
310
311           ensure-one-shell-regardless-of-mode:
312                   @echo Building $@ in `pwd`; \
313                   (cd ${.CURDIR} && ${.MAKE} $@); \
314                   echo Back in `pwd`
315
316VVAARRIIAABBLLEE AASSSSIIGGNNMMEENNTTSS
317     Variables in make are much like variables in the shell, and, by tradi-
318     tion, consist of all upper-case letters.
319
320   VVaarriiaabbllee aassssiiggnnmmeenntt mmooddiiffiieerrss
321     The five operators that can be used to assign values to variables are as
322     follows:
323
324     ==       Assign the value to the variable.  Any previous value is overrid-
325             den.
326
327     ++==      Append the value to the current value of the variable.
328
329     ??==      Assign the value to the variable if it is not already defined.
330
331     ::==      Assign with expansion, i.e. expand the value before assigning it
332             to the variable.  Normally, expansion is not done until the vari-
333             able is referenced.  _N_O_T_E: References to undefined variables are
334             _n_o_t expanded.  This can cause problems when variable modifiers
335             are used.
336
337     !!==      Expand the value and pass it to the shell for execution and
338             assign the result to the variable.  Any newlines in the result
339             are replaced with spaces.
340
341     Any white-space before the assigned _v_a_l_u_e is removed; if the value is
342     being appended, a single space is inserted between the previous contents
343     of the variable and the appended value.
344
345     Variables are expanded by surrounding the variable name with either curly
346     braces (`{}') or parentheses (`()') and preceding it with a dollar sign
347     (`$').  If the variable name contains only a single letter, the surround-
348     ing braces or parentheses are not required.  This shorter form is not
349     recommended.
350
351     If the variable name contains a dollar, then the name itself is expanded
352     first.  This allows almost arbitrary variable names, however names con-
353     taining dollar, braces, parenthesis, or whitespace are really best
354     avoided!
355
356     If the result of expanding a variable contains a dollar sign (`$') the
357     string is expanded again.
358
359     Variable substitution occurs at three distinct times, depending on where
360     the variable is being used.
361
362     1.   Variables in dependency lines are expanded as the line is read.
363
364     2.   Variables in shell commands are expanded when the shell command is
365          executed.
366
367     3.   ``.for'' loop index variables are expanded on each loop iteration.
368          Note that other variables are not expanded inside loops so the fol-
369          lowing example code:
370
371
372                .for i in 1 2 3
373                a+=     ${i}
374                j=      ${i}
375                b+=     ${j}
376                .endfor
377
378                all:
379                        @echo ${a}
380                        @echo ${b}
381
382          will print:
383
384                1 2 3
385                3 3 3
386
387          Because while ${a} contains ``1 2 3'' after the loop is executed,
388          ${b} contains ``${j} ${j} ${j}'' which expands to ``3 3 3'' since
389          after the loop completes ${j} contains ``3''.
390
391   VVaarriiaabbllee ccllaasssseess
392     The four different classes of variables (in order of increasing prece-
393     dence) are:
394
395     Environment variables
396             Variables defined as part of bbmmaakkee's environment.
397
398     Global variables
399             Variables defined in the makefile or in included makefiles.
400
401     Command line variables
402             Variables defined as part of the command line.
403
404     Local variables
405             Variables that are defined specific to a certain target.  The
406             seven local variables are as follows:
407
408             _._A_L_L_S_R_C   The list of all sources for this target; also known as
409                       `_>'.
410
411             _._A_R_C_H_I_V_E  The name of the archive file.
412
413             _._I_M_P_S_R_C   In suffix-transformation rules, the name/path of the
414                       source from which the target is to be transformed (the
415                       ``implied'' source); also known as `_<'.  It is not
416                       defined in explicit rules.
417
418             _._M_E_M_B_E_R   The name of the archive member.
419
420             _._O_O_D_A_T_E   The list of sources for this target that were deemed
421                       out-of-date; also known as `_?'.
422
423             _._P_R_E_F_I_X   The file prefix of the target, containing only the file
424                       portion, no suffix or preceding directory components;
425                       also known as `_*'.
426
427             _._T_A_R_G_E_T   The name of the target; also known as `_@'.
428
429             The shorter forms `_@', `_?', `_<', `_>', and `_*' are permitted for
430             backward compatibility with historical makefiles and are not rec-
431             ommended.  The six variables `_@_F', `_@_D', `_<_F', `_<_D', `_*_F', and
432             `_*_D' are permitted for compatibility with AT&T System V UNIX
433             makefiles and are not recommended.
434
435             Four of the local variables may be used in sources on dependency
436             lines because they expand to the proper value for each target on
437             the line.  These variables are `_._T_A_R_G_E_T', `_._P_R_E_F_I_X', `_._A_R_C_H_I_V_E',
438             and `_._M_E_M_B_E_R'.
439
440   AAddddiittiioonnaall bbuuiilltt--iinn vvaarriiaabblleess
441     In addition, bbmmaakkee sets or knows about the following variables:
442
443     _$               A single dollar sign `$', i.e.  `$$' expands to a single
444                     dollar sign.
445
446     _._A_L_L_T_A_R_G_E_T_S     The list of all targets encountered in the Makefile.  If
447                     evaluated during Makefile parsing, lists only those tar-
448                     gets encountered thus far.
449
450     _._C_U_R_D_I_R         A path to the directory where bbmmaakkee was executed.  Refer
451                     to the description of `PWD' for more details.
452
453     _._I_N_C_L_U_D_E_D_F_R_O_M_D_I_R
454                     The directory of the file this Makefile was included
455                     from.
456
457     _._I_N_C_L_U_D_E_D_F_R_O_M_F_I_L_E
458                     The filename of the file this Makefile was included from.
459
460     MAKE            The name that bbmmaakkee was executed with (_a_r_g_v_[_0_]).  For
461                     compatibility bbmmaakkee also sets _._M_A_K_E with the same value.
462                     The preferred variable to use is the environment variable
463                     MAKE because it is more compatible with other versions of
464                     bbmmaakkee and cannot be confused with the special target with
465                     the same name.
466
467     _._M_A_K_E_._D_E_P_E_N_D_F_I_L_E
468                     Names the makefile (default `_._d_e_p_e_n_d') from which gener-
469                     ated dependencies are read.
470
471     _._M_A_K_E_._E_X_P_A_N_D___V_A_R_I_A_B_L_E_S
472                     A boolean that controls the default behavior of the --VV
473                     option.
474
475     _._M_A_K_E_._E_X_P_O_R_T_E_D  The list of variables exported by bbmmaakkee.
476
477     _._M_A_K_E_._J_O_B_S      The argument to the --jj option.
478
479     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X
480                     If bbmmaakkee is run with _j then output for each target is
481                     prefixed with a token `--- target ---' the first part of
482                     which can be controlled via _._M_A_K_E_._J_O_B_._P_R_E_F_I_X.  If
483                     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X is empty, no token is printed.
484                     For example:
485                     .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
486                     would produce tokens like `---make[1234] target ---' mak-
487                     ing it easier to track the degree of parallelism being
488                     achieved.
489
490     MAKEFLAGS       The environment variable `MAKEFLAGS' may contain anything
491                     that may be specified on bbmmaakkee's command line.  Anything
492                     specified on bbmmaakkee's command line is appended to the
493                     `MAKEFLAGS' variable which is then entered into the envi-
494                     ronment for all programs which bbmmaakkee executes.
495
496     _._M_A_K_E_._L_E_V_E_L     The recursion depth of bbmmaakkee.  The initial instance of
497                     bbmmaakkee will be 0, and an incremented value is put into the
498                     environment to be seen by the next generation.  This
499                     allows tests like: .if ${.MAKE.LEVEL} == 0 to protect
500                     things which should only be evaluated in the initial
501                     instance of bbmmaakkee.
502
503     _._M_A_K_E_._M_A_K_E_F_I_L_E___P_R_E_F_E_R_E_N_C_E
504                     The ordered list of makefile names (default `_m_a_k_e_f_i_l_e',
505                     `_M_a_k_e_f_i_l_e') that bbmmaakkee will look for.
506
507     _._M_A_K_E_._M_A_K_E_F_I_L_E_S
508                     The list of makefiles read by bbmmaakkee, which is useful for
509                     tracking dependencies.  Each makefile is recorded only
510                     once, regardless of the number of times read.
511
512     _._M_A_K_E_._M_O_D_E      Processed after reading all makefiles.  Can affect the
513                     mode that bbmmaakkee runs in.  It can contain a number of key-
514                     words:
515
516                     _c_o_m_p_a_t      Like --BB, puts bbmmaakkee into "compat" mode.
517
518                     _m_e_t_a        Puts bbmmaakkee into "meta" mode, where meta files
519                                 are created for each target to capture the
520                                 command run, the output generated and if
521                                 filemon(4) is available, the system calls
522                                 which are of interest to bbmmaakkee.  The captured
523                                 output can be very useful when diagnosing
524                                 errors.
525
526                     _c_u_r_d_i_r_O_k_= _b_f Normally bbmmaakkee will not create .meta files
527                                 in `_._C_U_R_D_I_R'.  This can be overridden by set-
528                                 ting _b_f to a value which represents True.
529
530                     _e_n_v         For debugging, it can be useful to inlcude
531                                 the environment in the .meta file.
532
533                     _v_e_r_b_o_s_e     If in "meta" mode, print a clue about the
534                                 target being built.  This is useful if the
535                                 build is otherwise running silently.  The
536                                 message printed the value of:
537                                 _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X.
538
539                     _i_g_n_o_r_e_-_c_m_d  Some makefiles have commands which are simply
540                                 not stable.  This keyword causes them to be
541                                 ignored for determining whether a target is
542                                 out of date in "meta" mode.  See also
543                                 ..NNOOMMEETTAA__CCMMPP.
544
545                     _s_i_l_e_n_t_= _b_f  If _b_f is True, when a .meta file is created,
546                                 mark the target ..SSIILLEENNTT.
547
548     _._M_A_K_E_._M_E_T_A_._B_A_I_L_I_W_I_C_K
549                     In "meta" mode, provides a list of prefixes which match
550                     the directories controlled by bbmmaakkee.  If a file that was
551                     generated outside of _._O_B_J_D_I_R but within said bailiwick is
552                     missing, the current target is considered out-of-date.
553
554     _._M_A_K_E_._M_E_T_A_._C_R_E_A_T_E_D
555                     In "meta" mode, this variable contains a list of all the
556                     meta files updated.  If not empty, it can be used to
557                     trigger processing of _._M_A_K_E_._M_E_T_A_._F_I_L_E_S.
558
559     _._M_A_K_E_._M_E_T_A_._F_I_L_E_S
560                     In "meta" mode, this variable contains a list of all the
561                     meta files used (updated or not).  This list can be used
562                     to process the meta files to extract dependency informa-
563                     tion.
564
565     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___P_A_T_H_S
566                     Provides a list of path prefixes that should be ignored;
567                     because the contents are expected to change over time.
568                     The default list includes: `_/_d_e_v _/_e_t_c _/_p_r_o_c _/_t_m_p _/_v_a_r_/_r_u_n
569                     _/_v_a_r_/_t_m_p'
570
571     _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X
572                     Defines the message printed for each meta file updated in
573                     "meta verbose" mode.  The default value is:
574                           Building ${.TARGET:H:tA}/${.TARGET:T}
575
576     _._M_A_K_E_O_V_E_R_R_I_D_E_S  This variable is used to record the names of variables
577                     assigned to on the command line, so that they may be
578                     exported as part of `MAKEFLAGS'.  This behaviour can be
579                     disabled by assigning an empty value to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'
580                     within a makefile.  Extra variables can be exported from
581                     a makefile by appending their names to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'.
582                     `MAKEFLAGS' is re-exported whenever `_._M_A_K_E_O_V_E_R_R_I_D_E_S' is
583                     modified.
584
585     _._M_A_K_E_._P_A_T_H___F_I_L_E_M_O_N
586                     If bbmmaakkee was built with filemon(4) support, this is set
587                     to the path of the device node.  This allows makefiles to
588                     test for this support.
589
590     _._M_A_K_E_._P_I_D       The process-id of bbmmaakkee.
591
592     _._M_A_K_E_._P_P_I_D      The parent process-id of bbmmaakkee.
593
594     _M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R
595                     When bbmmaakkee stops due to an error, it prints its name and
596                     the value of `_._C_U_R_D_I_R' as well as the value of any vari-
597                     ables named in `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R'.
598
599     _._n_e_w_l_i_n_e        This variable is simply assigned a newline character as
600                     its value.  This allows expansions using the ::@@ modifier
601                     to put a newline between iterations of the loop rather
602                     than a space.  For example, the printing of
603                     `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R' could be done as
604                     ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
605
606     _._O_B_J_D_I_R         A path to the directory where the targets are built.  Its
607                     value is determined by trying to chdir(2) to the follow-
608                     ing directories in order and using the first match:
609
610                     1.   ${MAKEOBJDIRPREFIX}${.CURDIR}
611
612                          (Only if `MAKEOBJDIRPREFIX' is set in the environ-
613                          ment or on the command line.)
614
615                     2.   ${MAKEOBJDIR}
616
617                          (Only if `MAKEOBJDIR' is set in the environment or
618                          on the command line.)
619
620                     3.   ${.CURDIR}_/_o_b_j_.${MACHINE}
621
622                     4.   ${.CURDIR}_/_o_b_j
623
624                     5.   _/_u_s_r_/_o_b_j_/${.CURDIR}
625
626                     6.   ${.CURDIR}
627
628                     Variable expansion is performed on the value before it's
629                     used, so expressions such as
630                           ${.CURDIR:S,^/usr/src,/var/obj,}
631                     may be used.  This is especially useful with
632                     `MAKEOBJDIR'.
633
634                     `_._O_B_J_D_I_R' may be modified in the makefile as a global
635                     variable.  In all cases, bbmmaakkee will chdir(2) to `_._O_B_J_D_I_R'
636                     and set `PWD' to that directory before executing any tar-
637                     gets.
638
639     _._P_A_R_S_E_D_I_R       A path to the directory of the current `_M_a_k_e_f_i_l_e' being
640                     parsed.
641
642     _._P_A_R_S_E_F_I_L_E      The basename of the current `_M_a_k_e_f_i_l_e' being parsed.
643                     This variable and `_._P_A_R_S_E_D_I_R' are both set only while the
644                     `_M_a_k_e_f_i_l_e_s' are being parsed.  If you want to retain
645                     their current values, assign them to a variable using
646                     assignment with expansion: (`::==').
647
648     _._P_A_T_H           A variable that represents the list of directories that
649                     bbmmaakkee will search for files.  The search list should be
650                     updated using the target `_._P_A_T_H' rather than the vari-
651                     able.
652
653     PWD             Alternate path to the current directory.  bbmmaakkee normally
654                     sets `_._C_U_R_D_I_R' to the canonical path given by getcwd(3).
655                     However, if the environment variable `PWD' is set and
656                     gives a path to the current directory, then bbmmaakkee sets
657                     `_._C_U_R_D_I_R' to the value of `PWD' instead.  This behaviour
658                     is disabled if `MAKEOBJDIRPREFIX' is set or `MAKEOBJDIR'
659                     contains a variable transform.  `PWD' is set to the value
660                     of `_._O_B_J_D_I_R' for all programs which bbmmaakkee executes.
661
662     .TARGETS        The list of targets explicitly specified on the command
663                     line, if any.
664
665     VPATH           Colon-separated (``:'') lists of directories that bbmmaakkee
666                     will search for files.  The variable is supported for
667                     compatibility with old make programs only, use `_._P_A_T_H'
668                     instead.
669
670   VVaarriiaabbllee mmooddiiffiieerrss
671     Variable expansion may be modified to select or modify each word of the
672     variable (where a ``word'' is white-space delimited sequence of charac-
673     ters).  The general format of a variable expansion is as follows:
674
675           ${variable[:modifier[:...]]}
676
677     Each modifier begins with a colon, which may be escaped with a backslash
678     (`\').
679
680     A set of modifiers can be specified via a variable, as follows:
681
682           modifier_variable=modifier[:...]
683           ${variable:${modifier_variable}[:...]}
684
685     In this case the first modifier in the modifier_variable does not start
686     with a colon, since that must appear in the referencing variable.  If any
687     of the modifiers in the modifier_variable contain a dollar sign (`$'),
688     these must be doubled to avoid early expansion.
689
690     The supported modifiers are:
691
692     ::EE   Replaces each word in the variable with its suffix.
693
694     ::HH   Replaces each word in the variable with everything but the last com-
695          ponent.
696
697     ::MM_p_a_t_t_e_r_n
698          Select only those words that match _p_a_t_t_e_r_n.  The standard shell
699          wildcard characters (`*', `?', and `[]') may be used.  The wildcard
700          characters may be escaped with a backslash (`\').  As a consequence
701          of the way values are split into words, matched, and then joined, a
702          construct like
703                ${VAR:M*}
704          will normalise the inter-word spacing, removing all leading and
705          trailing space, and converting multiple consecutive spaces to single
706          spaces.
707
708     ::NN_p_a_t_t_e_r_n
709          This is identical to `::MM', but selects all words which do not match
710          _p_a_t_t_e_r_n.
711
712     ::OO   Order every word in variable alphabetically.  To sort words in
713          reverse order use the `::OO::[[--11....11]]' combination of modifiers.
714
715     ::OOxx  Randomize words in variable.  The results will be different each
716          time you are referring to the modified variable; use the assignment
717          with expansion (`::==') to prevent such behaviour.  For example,
718
719                LIST=                   uno due tre quattro
720                RANDOM_LIST=            ${LIST:Ox}
721                STATIC_RANDOM_LIST:=    ${LIST:Ox}
722
723                all:
724                        @echo "${RANDOM_LIST}"
725                        @echo "${RANDOM_LIST}"
726                        @echo "${STATIC_RANDOM_LIST}"
727                        @echo "${STATIC_RANDOM_LIST}"
728          may produce output similar to:
729
730                quattro due tre uno
731                tre due quattro uno
732                due uno quattro tre
733                due uno quattro tre
734
735     ::QQ   Quotes every shell meta-character in the variable, so that it can be
736          passed safely through recursive invocations of bbmmaakkee.
737
738     ::RR   Replaces each word in the variable with everything but its suffix.
739
740     ::ggmmttiimmee
741          The value is a format string for strftime(3), using the current
742          gmtime(3).
743
744     ::hhaasshh
745          Compute a 32bit hash of the value and encode it as hex digits.
746
747     ::llooccaallttiimmee
748          The value is a format string for strftime(3), using the current
749          localtime(3).
750
751     ::ttAA  Attempt to convert variable to an absolute path using realpath(3),
752          if that fails, the value is unchanged.
753
754     ::ttll  Converts variable to lower-case letters.
755
756     ::ttss_c
757          Words in the variable are normally separated by a space on expan-
758          sion.  This modifier sets the separator to the character _c.  If _c is
759          omitted, then no separator is used.  The common escapes (including
760          octal numeric codes), work as expected.
761
762     ::ttuu  Converts variable to upper-case letters.
763
764     ::ttWW  Causes the value to be treated as a single word (possibly containing
765          embedded white space).  See also `::[[**]]'.
766
767     ::ttww  Causes the value to be treated as a sequence of words delimited by
768          white space.  See also `::[[@@]]'.
769
770     ::SS/_o_l_d___s_t_r_i_n_g/_n_e_w___s_t_r_i_n_g/[11ggWW]
771          Modify the first occurrence of _o_l_d___s_t_r_i_n_g in the variable's value,
772          replacing it with _n_e_w___s_t_r_i_n_g.  If a `g' is appended to the last
773          slash of the pattern, all occurrences in each word are replaced.  If
774          a `1' is appended to the last slash of the pattern, only the first
775          word is affected.  If a `W' is appended to the last slash of the
776          pattern, then the value is treated as a single word (possibly con-
777          taining embedded white space).  If _o_l_d___s_t_r_i_n_g begins with a caret
778          (`^'), _o_l_d___s_t_r_i_n_g is anchored at the beginning of each word.  If
779          _o_l_d___s_t_r_i_n_g ends with a dollar sign (`$'), it is anchored at the end
780          of each word.  Inside _n_e_w___s_t_r_i_n_g, an ampersand (`&') is replaced by
781          _o_l_d___s_t_r_i_n_g (without any `^' or `$').  Any character may be used as a
782          delimiter for the parts of the modifier string.  The anchoring,
783          ampersand and delimiter characters may be escaped with a backslash
784          (`\').
785
786          Variable expansion occurs in the normal fashion inside both
787          _o_l_d___s_t_r_i_n_g and _n_e_w___s_t_r_i_n_g with the single exception that a backslash
788          is used to prevent the expansion of a dollar sign (`$'), not a pre-
789          ceding dollar sign as is usual.
790
791     ::CC/_p_a_t_t_e_r_n/_r_e_p_l_a_c_e_m_e_n_t/[11ggWW]
792          The ::CC modifier is just like the ::SS modifier except that the old and
793          new strings, instead of being simple strings, are an extended regu-
794          lar expression (see regex(3)) string _p_a_t_t_e_r_n and an ed(1)-style
795          string _r_e_p_l_a_c_e_m_e_n_t.  Normally, the first occurrence of the pattern
796          _p_a_t_t_e_r_n in each word of the value is substituted with _r_e_p_l_a_c_e_m_e_n_t.
797          The `1' modifier causes the substitution to apply to at most one
798          word; the `g' modifier causes the substitution to apply to as many
799          instances of the search pattern _p_a_t_t_e_r_n as occur in the word or
800          words it is found in; the `W' modifier causes the value to be
801          treated as a single word (possibly containing embedded white space).
802          Note that `1' and `g' are orthogonal; the former specifies whether
803          multiple words are potentially affected, the latter whether multiple
804          substitutions can potentially occur within each affected word.
805
806          As for the ::SS modifier, the _p_a_t_t_e_r_n and _r_e_p_l_a_c_e_m_e_n_t are subjected to
807          variable expansion before being parsed as regular expressions.
808
809     ::TT   Replaces each word in the variable with its last component.
810
811     ::uu   Remove adjacent duplicate words (like uniq(1)).
812
813     ::??_t_r_u_e___s_t_r_i_n_g::_f_a_l_s_e___s_t_r_i_n_g
814          If the variable name (not its value), when parsed as a .if condi-
815          tional expression, evaluates to true, return as its value the
816          _t_r_u_e___s_t_r_i_n_g, otherwise return the _f_a_l_s_e___s_t_r_i_n_g.  Since the variable
817          name is used as the expression, :? must be the first modifier after
818          the variable name itself - which will, of course, usually contain
819          variable expansions.  A common error is trying to use expressions
820          like
821                ${NUMBERS:M42:?match:no}
822          which actually tests defined(NUMBERS), to determine is any words
823          match "42" you need to use something like:
824                ${"${NUMBERS:M42}" != "":?match:no}.
825
826     _:_o_l_d___s_t_r_i_n_g_=_n_e_w___s_t_r_i_n_g
827          This is the AT&T System V UNIX style variable substitution.  It must
828          be the last modifier specified.  If _o_l_d___s_t_r_i_n_g or _n_e_w___s_t_r_i_n_g do not
829          contain the pattern matching character _% then it is assumed that
830          they are anchored at the end of each word, so only suffixes or
831          entire words may be replaced.  Otherwise _% is the substring of
832          _o_l_d___s_t_r_i_n_g to be replaced in _n_e_w___s_t_r_i_n_g.
833
834          Variable expansion occurs in the normal fashion inside both
835          _o_l_d___s_t_r_i_n_g and _n_e_w___s_t_r_i_n_g with the single exception that a backslash
836          is used to prevent the expansion of a dollar sign (`$'), not a pre-
837          ceding dollar sign as is usual.
838
839     ::@@_t_e_m_p@@_s_t_r_i_n_g@@
840          This is the loop expansion mechanism from the OSF Development Envi-
841          ronment (ODE) make.  Unlike ..ffoorr loops expansion occurs at the time
842          of reference.  Assign _t_e_m_p to each word in the variable and evaluate
843          _s_t_r_i_n_g.  The ODE convention is that _t_e_m_p should start and end with a
844          period.  For example.
845                ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
846
847          However a single character variable is often more readable:
848                ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
849
850     ::UU_n_e_w_v_a_l
851          If the variable is undefined _n_e_w_v_a_l is the value.  If the variable
852          is defined, the existing value is returned.  This is another ODE
853          make feature.  It is handy for setting per-target CFLAGS for
854          instance:
855                ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
856          If a value is only required if the variable is undefined, use:
857                ${VAR:D:Unewval}
858
859     ::DD_n_e_w_v_a_l
860          If the variable is defined _n_e_w_v_a_l is the value.
861
862     ::LL   The name of the variable is the value.
863
864     ::PP   The path of the node which has the same name as the variable is the
865          value.  If no such node exists or its path is null, then the name of
866          the variable is used.  In order for this modifier to work, the name
867          (node) must at least have appeared on the rhs of a dependency.
868
869     ::!!_c_m_d!!
870          The output of running _c_m_d is the value.
871
872     ::sshh  If the variable is non-empty it is run as a command and the output
873          becomes the new value.
874
875     ::::==_s_t_r
876          The variable is assigned the value _s_t_r after substitution.  This
877          modifier and its variations are useful in obscure situations such as
878          wanting to set a variable when shell commands are being parsed.
879          These assignment modifiers always expand to nothing, so if appearing
880          in a rule line by themselves should be preceded with something to
881          keep bbmmaakkee happy.
882
883          The `::::' helps avoid false matches with the AT&T System V UNIX style
884          ::== modifier and since substitution always occurs the ::::== form is
885          vaguely appropriate.
886
887     ::::??==_s_t_r
888          As for ::::== but only if the variable does not already have a value.
889
890     ::::++==_s_t_r
891          Append _s_t_r to the variable.
892
893     ::::!!==_c_m_d
894          Assign the output of _c_m_d to the variable.
895
896     ::[[_r_a_n_g_e]]
897          Selects one or more words from the value, or performs other opera-
898          tions related to the way in which the value is divided into words.
899
900          Ordinarily, a value is treated as a sequence of words delimited by
901          white space.  Some modifiers suppress this behaviour, causing a
902          value to be treated as a single word (possibly containing embedded
903          white space).  An empty value, or a value that consists entirely of
904          white-space, is treated as a single word.  For the purposes of the
905          `::[[]]' modifier, the words are indexed both forwards using positive
906          integers (where index 1 represents the first word), and backwards
907          using negative integers (where index -1 represents the last word).
908
909          The _r_a_n_g_e is subjected to variable expansion, and the expanded
910          result is then interpreted as follows:
911
912          _i_n_d_e_x  Selects a single word from the value.
913
914          _s_t_a_r_t...._e_n_d
915                 Selects all words from _s_t_a_r_t to _e_n_d, inclusive.  For example,
916                 `::[[22....--11]]' selects all words from the second word to the last
917                 word.  If _s_t_a_r_t is greater than _e_n_d, then the words are out-
918                 put in reverse order.  For example, `::[[--11....11]]' selects all
919                 the words from last to first.
920
921          **      Causes subsequent modifiers to treat the value as a single
922                 word (possibly containing embedded white space).  Analogous
923                 to the effect of "$*" in Bourne shell.
924
925          0      Means the same as `::[[**]]'.
926
927          @@      Causes subsequent modifiers to treat the value as a sequence
928                 of words delimited by white space.  Analogous to the effect
929                 of "$@" in Bourne shell.
930
931          ##      Returns the number of words in the value.
932
933IINNCCLLUUDDEE SSTTAATTEEMMEENNTTSS,, CCOONNDDIITTIIOONNAALLSS AANNDD FFOORR LLOOOOPPSS
934     Makefile inclusion, conditional structures and for loops  reminiscent of
935     the C programming language are provided in bbmmaakkee.  All such structures
936     are identified by a line beginning with a single dot (`.') character.
937     Files are included with either ..iinncclluuddee <_f_i_l_e> or ..iinncclluuddee "_f_i_l_e".  Vari-
938     ables between the angle brackets or double quotes are expanded to form
939     the file name.  If angle brackets are used, the included makefile is
940     expected to be in the system makefile directory.  If double quotes are
941     used, the including makefile's directory and any directories specified
942     using the --II option are searched before the system makefile directory.
943     For compatibility with other versions of bbmmaakkee `include file ...' is also
944     accepted.  If the include statement is written as ..--iinncclluuddee or as
945     ..ssiinncclluuddee then errors locating and/or opening include files are ignored.
946
947     Conditional expressions are also preceded by a single dot as the first
948     character of a line.  The possible conditionals are as follows:
949
950     ..eerrrroorr _m_e_s_s_a_g_e
951             The message is printed along with the name of the makefile and
952             line number, then bbmmaakkee will exit.
953
954     ..eexxppoorrtt _v_a_r_i_a_b_l_e _._._.
955             Export the specified global variable.  If no variable list is
956             provided, all globals are exported except for internal variables
957             (those that start with `.').  This is not affected by the --XX
958             flag, so should be used with caution.  For compatibility with
959             other bbmmaakkee programs `export variable=value' is also accepted.
960
961             Appending a variable name to _._M_A_K_E_._E_X_P_O_R_T_E_D is equivalent to
962             exporting a variable.
963
964     ..eexxppoorrtt--eennvv _v_a_r_i_a_b_l_e _._._.
965             The same as `.export', except that the variable is not appended
966             to _._M_A_K_E_._E_X_P_O_R_T_E_D.  This allows exporting a value to the environ-
967             ment which is different from that used by bbmmaakkee internally.
968
969     ..iinnffoo _m_e_s_s_a_g_e
970             The message is printed along with the name of the makefile and
971             line number.
972
973     ..uunnddeeff _v_a_r_i_a_b_l_e
974             Un-define the specified global variable.  Only global variables
975             may be un-defined.
976
977     ..uunneexxppoorrtt _v_a_r_i_a_b_l_e _._._.
978             The opposite of `.export'.  The specified global _v_a_r_i_a_b_l_e will be
979             removed from _._M_A_K_E_._E_X_P_O_R_T_E_D.  If no variable list is provided,
980             all globals are unexported, and _._M_A_K_E_._E_X_P_O_R_T_E_D deleted.
981
982     ..uunneexxppoorrtt--eennvv
983             Unexport all globals previously exported and clear the environ-
984             ment inherited from the parent.  This operation will cause a mem-
985             ory leak of the original environment, so should be used spar-
986             ingly.  Testing for _._M_A_K_E_._L_E_V_E_L being 0, would make sense.  Also
987             note that any variables which originated in the parent environ-
988             ment should be explicitly preserved if desired.  For example:
989
990                   .if ${.MAKE.LEVEL} == 0
991                   PATH := ${PATH}
992                   .unexport-env
993                   .export PATH
994                   .endif
995
996             Would result in an environment containing only `PATH', which is
997             the minimal useful environment.  Actually `.MAKE.LEVEL' will also
998             be pushed into the new environment.
999
1000     ..wwaarrnniinngg _m_e_s_s_a_g_e
1001             The message prefixed by `_w_a_r_n_i_n_g_:' is printed along with the name
1002             of the makefile and line number.
1003
1004     ..iiff [!]_e_x_p_r_e_s_s_i_o_n [_o_p_e_r_a_t_o_r _e_x_p_r_e_s_s_i_o_n _._._.]
1005             Test the value of an expression.
1006
1007     ..iiffddeeff [!]_v_a_r_i_a_b_l_e [_o_p_e_r_a_t_o_r _v_a_r_i_a_b_l_e _._._.]
1008             Test the value of a variable.
1009
1010     ..iiffnnddeeff [!]_v_a_r_i_a_b_l_e [_o_p_e_r_a_t_o_r _v_a_r_i_a_b_l_e _._._.]
1011             Test the value of a variable.
1012
1013     ..iiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1014             Test the target being built.
1015
1016     ..iiffnnmmaakkee [!] _t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1017             Test the target being built.
1018
1019     ..eellssee   Reverse the sense of the last conditional.
1020
1021     ..eelliiff [!] _e_x_p_r_e_s_s_i_o_n [_o_p_e_r_a_t_o_r _e_x_p_r_e_s_s_i_o_n _._._.]
1022             A combination of `..eellssee' followed by `..iiff'.
1023
1024     ..eelliiffddeeff [!]_v_a_r_i_a_b_l_e [_o_p_e_r_a_t_o_r _v_a_r_i_a_b_l_e _._._.]
1025             A combination of `..eellssee' followed by `..iiffddeeff'.
1026
1027     ..eelliiffnnddeeff [!]_v_a_r_i_a_b_l_e [_o_p_e_r_a_t_o_r _v_a_r_i_a_b_l_e _._._.]
1028             A combination of `..eellssee' followed by `..iiffnnddeeff'.
1029
1030     ..eelliiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1031             A combination of `..eellssee' followed by `..iiffmmaakkee'.
1032
1033     ..eelliiffnnmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1034             A combination of `..eellssee' followed by `..iiffnnmmaakkee'.
1035
1036     ..eennddiiff  End the body of the conditional.
1037
1038     The _o_p_e_r_a_t_o_r may be any one of the following:
1039
1040     ||||     Logical OR.
1041
1042     &&&&     Logical AND; of higher precedence than ``||''.
1043
1044     As in C, bbmmaakkee will only evaluate a conditional as far as is necessary to
1045     determine its value.  Parentheses may be used to change the order of
1046     evaluation.  The boolean operator `!!' may be used to logically negate an
1047     entire conditional.  It is of higher precedence than `&&&&'.
1048
1049     The value of _e_x_p_r_e_s_s_i_o_n may be any of the following:
1050
1051     ddeeffiinneedd  Takes a variable name as an argument and evaluates to true if
1052              the variable has been defined.
1053
1054     mmaakkee     Takes a target name as an argument and evaluates to true if the
1055              target was specified as part of bbmmaakkee's command line or was
1056              declared the default target (either implicitly or explicitly,
1057              see _._M_A_I_N) before the line containing the conditional.
1058
1059     eemmppttyy    Takes a variable, with possible modifiers, and evaluates to true
1060              if the expansion of the variable would result in an empty
1061              string.
1062
1063     eexxiissttss   Takes a file name as an argument and evaluates to true if the
1064              file exists.  The file is searched for on the system search path
1065              (see _._P_A_T_H).
1066
1067     ttaarrggeett   Takes a target name as an argument and evaluates to true if the
1068              target has been defined.
1069
1070     ccoommmmaannddss
1071              Takes a target name as an argument and evaluates to true if the
1072              target has been defined and has commands associated with it.
1073
1074     _E_x_p_r_e_s_s_i_o_n may also be an arithmetic or string comparison.  Variable
1075     expansion is performed on both sides of the comparison, after which the
1076     integral values are compared.  A value is interpreted as hexadecimal if
1077     it is preceded by 0x, otherwise it is decimal; octal numbers are not sup-
1078     ported.  The standard C relational operators are all supported.  If after
1079     variable expansion, either the left or right hand side of a `====' or `!!=='
1080     operator is not an integral value, then string comparison is performed
1081     between the expanded variables.  If no relational operator is given, it
1082     is assumed that the expanded variable is being compared against 0 or an
1083     empty string in the case of a string comparison.
1084
1085     When bbmmaakkee is evaluating one of these conditional expressions, and it
1086     encounters a (white-space separated) word it doesn't recognize, either
1087     the ``make'' or ``defined'' expression is applied to it, depending on the
1088     form of the conditional.  If the form is `..iiffddeeff', `..iiffnnddeeff', or `..iiff'
1089     the ``defined'' expression is applied.  Similarly, if the form is
1090     `..iiffmmaakkee' or `..iiffnnmmaakkee, tthhee' ``make'' expression is applied.
1091
1092     If the conditional evaluates to true the parsing of the makefile contin-
1093     ues as before.  If it evaluates to false, the following lines are
1094     skipped.  In both cases this continues until a `..eellssee' or `..eennddiiff' is
1095     found.
1096
1097     For loops are typically used to apply a set of rules to a list of files.
1098     The syntax of a for loop is:
1099
1100     ..ffoorr _v_a_r_i_a_b_l_e [_v_a_r_i_a_b_l_e _._._.] iinn _e_x_p_r_e_s_s_i_o_n
1101     <make-rules>
1102     ..eennddffoorr
1103
1104     After the for eexxpprreessssiioonn is evaluated, it is split into words.  On each
1105     iteration of the loop, one word is taken and assigned to each vvaarriiaabbllee,
1106     in order, and these vvaarriiaabblleess are substituted into the mmaakkee--rruulleess inside
1107     the body of the for loop.  The number of words must come out even; that
1108     is, if there are three iteration variables, the number of words provided
1109     must be a multiple of three.
1110
1111CCOOMMMMEENNTTSS
1112     Comments begin with a hash (`#') character, anywhere but in a shell com-
1113     mand line, and continue to the end of an unescaped new line.
1114
1115SSPPEECCIIAALL SSOOUURRCCEESS ((AATTTTRRIIBBUUTTEESS))
1116     ..EEXXEECC     Target is never out of date, but always execute commands any-
1117               way.
1118
1119     ..IIGGNNOORREE   Ignore any errors from the commands associated with this tar-
1120               get, exactly as if they all were preceded by a dash (`-').
1121
1122     ..MMAADDEE     Mark all sources of this target as being up-to-date.
1123
1124     ..MMAAKKEE     Execute the commands associated with this target even if the --nn
1125               or --tt options were specified.  Normally used to mark recursive
1126               bbmmaakkees.
1127
1128     ..MMEETTAA     Create a meta file for the target, even if it is flagged as
1129               ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL.  Usage in conjunction with ..MMAAKKEE is
1130               the most likely case.  In "meta" mode, the target is out-of-
1131               date if the meta file is missing.
1132
1133     ..NNOOMMEETTAA   Do not create a meta file for the target.  Meta files are also
1134               not created for ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL targets.
1135
1136     ..NNOOMMEETTAA__CCMMPP
1137               Ignore differences in commands when deciding if target is out
1138               of date.  This is useful if the command contains a value which
1139               always changes.  If the number of commands change, though, the
1140               target will still be out of date.  The same effect applies to
1141               any command line that uses the variable _._O_O_D_A_T_E, which can be
1142               used for that purpose even when not otherwise needed or
1143               desired:
1144
1145
1146                     skip-compare-for-some:
1147                             @echo this will be compared
1148                             @echo this will not ${.OODATE:M.NOMETA_CMP}
1149                             @echo this will also be compared
1150
1151               The ::MM pattern suppresses any expansion of the unwanted vari-
1152               able.
1153
1154     ..NNOOPPAATTHH   Do not search for the target in the directories specified by
1155               ..PPAATTHH.
1156
1157     ..NNOOTTMMAAIINN  Normally bbmmaakkee selects the first target it encounters as the
1158               default target to be built if no target was specified.  This
1159               source prevents this target from being selected.
1160
1161     ..OOPPTTIIOONNAALL
1162               If a target is marked with this attribute and bbmmaakkee can't fig-
1163               ure out how to create it, it will ignore this fact and assume
1164               the file isn't needed or already exists.
1165
1166     ..PPHHOONNYY    The target does not correspond to an actual file; it is always
1167               considered to be out of date, and will not be created with the
1168               --tt option.  Suffix-transformation rules are not applied to
1169               ..PPHHOONNYY targets.
1170
1171     ..PPRREECCIIOOUUSS
1172               When bbmmaakkee is interrupted, it normally removes any partially
1173               made targets.  This source prevents the target from being
1174               removed.
1175
1176     ..RREECCUURRSSIIVVEE
1177               Synonym for ..MMAAKKEE.
1178
1179     ..SSIILLEENNTT   Do not echo any of the commands associated with this target,
1180               exactly as if they all were preceded by an at sign (`@').
1181
1182     ..UUSSEE      Turn the target into bbmmaakkee's version of a macro.  When the tar-
1183               get is used as a source for another target, the other target
1184               acquires the commands, sources, and attributes (except for
1185               ..UUSSEE) of the source.  If the target already has commands, the
1186               ..UUSSEE target's commands are appended to them.
1187
1188     ..UUSSEEBBEEFFOORREE
1189               Exactly like ..UUSSEE, but prepend the ..UUSSEEBBEEFFOORREE target commands
1190               to the target.
1191
1192     ..WWAAIITT     If ..WWAAIITT appears in a dependency line, the sources that precede
1193               it are made before the sources that succeed it in the line.
1194               Since the dependents of files are not made until the file
1195               itself could be made, this also stops the dependents being
1196               built unless they are needed for another branch of the depen-
1197               dency tree.  So given:
1198
1199               x: a .WAIT b
1200                       echo x
1201               a:
1202                       echo a
1203               b: b1
1204                       echo b
1205               b1:
1206                       echo b1
1207
1208               the output is always `a', `b1', `b', `x'.
1209               The ordering imposed by ..WWAAIITT is only relevant for parallel
1210               makes.
1211
1212SSPPEECCIIAALL TTAARRGGEETTSS
1213     Special targets may not be included with other targets, i.e. they must be
1214     the only target specified.
1215
1216     ..BBEEGGIINN   Any command lines attached to this target are executed before
1217              anything else is done.
1218
1219     ..DDEEFFAAUULLTT
1220              This is sort of a ..UUSSEE rule for any target (that was used only
1221              as a source) that bbmmaakkee can't figure out any other way to cre-
1222              ate.  Only the shell script is used.  The ..IIMMPPSSRRCC variable of a
1223              target that inherits ..DDEEFFAAUULLTT's commands is set to the target's
1224              own name.
1225
1226     ..EENNDD     Any command lines attached to this target are executed after
1227              everything else is done.
1228
1229     ..EERRRROORR   Any command lines attached to this target are executed when
1230              another target fails.  The ..EERRRROORR__TTAARRGGEETT variable is set to the
1231              target that failed.  See also MMAAKKEE__PPRRIINNTT__VVAARR__OONN__EERRRROORR.
1232
1233     ..IIGGNNOORREE  Mark each of the sources with the ..IIGGNNOORREE attribute.  If no
1234              sources are specified, this is the equivalent of specifying the
1235              --ii option.
1236
1237     ..IINNTTEERRRRUUPPTT
1238              If bbmmaakkee is interrupted, the commands for this target will be
1239              executed.
1240
1241     ..MMAAIINN    If no target is specified when bbmmaakkee is invoked, this target
1242              will be built.
1243
1244     ..MMAAKKEEFFLLAAGGSS
1245              This target provides a way to specify flags for bbmmaakkee when the
1246              makefile is used.  The flags are as if typed to the shell,
1247              though the --ff option will have no effect.
1248
1249     ..NNOOPPAATTHH  Apply the ..NNOOPPAATTHH attribute to any specified sources.
1250
1251     ..NNOOTTPPAARRAALLLLEELL
1252              Disable parallel mode.
1253
1254     ..NNOO__PPAARRAALLLLEELL
1255              Synonym for ..NNOOTTPPAARRAALLLLEELL, for compatibility with other pmake
1256              variants.
1257
1258     ..OORRDDEERR   The named targets are made in sequence.  This ordering does not
1259              add targets to the list of targets to be made.  Since the depen-
1260              dents of a target do not get built until the target itself could
1261              be built, unless `a' is built by another part of the dependency
1262              graph, the following is a dependency loop:
1263
1264              .ORDER: b a
1265              b: a
1266
1267              The ordering imposed by ..OORRDDEERR is only relevant for parallel
1268              makes.
1269
1270     ..PPAATTHH    The sources are directories which are to be searched for files
1271              not found in the current directory.  If no sources are speci-
1272              fied, any previously specified directories are deleted.  If the
1273              source is the special ..DDOOTTLLAASSTT target, then the current working
1274              directory is searched last.
1275
1276     ..PPAATTHH.._s_u_f_f_i_x
1277              Like ..PPAATTHH but applies only to files with a particular suffix.
1278              The suffix must have been previously declared with ..SSUUFFFFIIXXEESS.
1279
1280     ..PPHHOONNYY   Apply the ..PPHHOONNYY attribute to any specified sources.
1281
1282     ..PPRREECCIIOOUUSS
1283              Apply the ..PPRREECCIIOOUUSS attribute to any specified sources.  If no
1284              sources are specified, the ..PPRREECCIIOOUUSS attribute is applied to
1285              every target in the file.
1286
1287     ..SSHHEELLLL   Sets the shell that bbmmaakkee will use to execute commands.  The
1288              sources are a set of _f_i_e_l_d_=_v_a_l_u_e pairs.
1289
1290              _n_a_m_e        This is the minimal specification, used to select
1291                          one of the builtin shell specs; _s_h, _k_s_h, and _c_s_h.
1292
1293              _p_a_t_h        Specifies the path to the shell.
1294
1295              _h_a_s_E_r_r_C_t_l   Indicates whether the shell supports exit on error.
1296
1297              _c_h_e_c_k       The command to turn on error checking.
1298
1299              _i_g_n_o_r_e      The command to disable error checking.
1300
1301              _e_c_h_o        The command to turn on echoing of commands executed.
1302
1303              _q_u_i_e_t       The command to turn off echoing of commands exe-
1304                          cuted.
1305
1306              _f_i_l_t_e_r      The output to filter after issuing the _q_u_i_e_t com-
1307                          mand.  It is typically identical to _q_u_i_e_t.
1308
1309              _e_r_r_F_l_a_g     The flag to pass the shell to enable error checking.
1310
1311              _e_c_h_o_F_l_a_g    The flag to pass the shell to enable command echo-
1312                          ing.
1313
1314              _n_e_w_l_i_n_e     The string literal to pass the shell that results in
1315                          a single newline character when used outside of any
1316                          quoting characters.
1317              Example:
1318
1319              .SHELL: name=ksh path=/bin/ksh hasErrCtl=true \
1320                      check="set -e" ignore="set +e" \
1321                      echo="set -v" quiet="set +v" filter="set +v" \
1322                      echoFlag=v errFlag=e newline="'\n'"
1323
1324     ..SSIILLEENNTT  Apply the ..SSIILLEENNTT attribute to any specified sources.  If no
1325              sources are specified, the ..SSIILLEENNTT attribute is applied to every
1326              command in the file.
1327
1328     ..SSTTAALLEE   This target gets run when a dependency file contains stale
1329              entries, having _._A_L_L_S_R_C set to the name of that dependency file.
1330
1331     ..SSUUFFFFIIXXEESS
1332              Each source specifies a suffix to bbmmaakkee.  If no sources are
1333              specified, any previously specified suffixes are deleted.  It
1334              allows the creation of suffix-transformation rules.
1335
1336              Example:
1337
1338              .SUFFIXES: .o
1339              .c.o:
1340                      cc -o ${.TARGET} -c ${.IMPSRC}
1341
1342EENNVVIIRROONNMMEENNTT
1343     bbmmaakkee uses the following environment variables, if they exist: MACHINE,
1344     MACHINE_ARCH, MAKE, MAKEFLAGS, MAKEOBJDIR, MAKEOBJDIRPREFIX, MAKESYSPATH,
1345     PWD, and TMPDIR.
1346
1347     MAKEOBJDIRPREFIX and MAKEOBJDIR may only be set in the environment or on
1348     the command line to bbmmaakkee and not as makefile variables; see the descrip-
1349     tion of `_._O_B_J_D_I_R' for more details.
1350
1351FFIILLEESS
1352     .depend        list of dependencies
1353     Makefile       list of dependencies
1354     makefile       list of dependencies
1355     sys.mk         system makefile
1356     /usr/share/mk  system makefile directory
1357
1358CCOOMMPPAATTIIBBIILLIITTYY
1359     The basic make syntax is compatible between different versions of make,
1360     however the special variables, variable modifiers and conditionals are
1361     not.
1362
1363     The way that parallel makes are scheduled changed in NetBSD 4.0 so that
1364     .ORDER and .WAIT apply recursively to the dependent nodes.  The algo-
1365     rithms used may change again in the future.
1366
1367     The way that .for loop variables are substituted changed after NetBSD 5.0
1368     so that they still appear to be variable expansions.  In particular this
1369     stops them being treated as syntax, and removes some obscure problems
1370     using them in .if statements.
1371
1372SSEEEE AALLSSOO
1373     mkdep(1)
1374
1375HHIISSTTOORRYY
1376     bbmmaakkee is derived from NetBSD make(1).  It uses autoconf to facilitate
1377     portability to other platforms.
1378
1379     A make command appeared in Version 7 AT&T UNIX.  This make implementation
1380     is based on Adam De Boor's pmake program which was written for Sprite at
1381     Berkeley.  It was designed to be a parallel distributed make running jobs
1382     on different machines using a daemon called ``customs''.
1383
1384     Historically the target/dependency ``FRC'' has been used to FoRCe
1385     rebuilding (since the target/dependency does not exist... unless someone
1386     creates an ``FRC'' file).
1387
1388BBUUGGSS
1389     The make syntax is difficult to parse without actually acting of the
1390     data.  For instance finding the end of a variable use should involve
1391     scanning each the modifiers using the correct terminator for each field.
1392     In many places make just counts {} and () in order to find the end of a
1393     variable expansion.
1394
1395     There is no way of escaping a space character in a filename.
1396
1397NetBSD 5.1                     February 14, 2014                    NetBSD 5.1
1398