xref: /freebsd/contrib/bmake/bmake.cat1 (revision 30da6877944eb2add9424fe1c65db9f8d6198416)
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             _x       Run shell commands with --xx so the actual commands are
126                     printed as they are executed.
127
128     --ee      Specify that environment variables override macro assignments
129             within makefiles.
130
131     --ff _m_a_k_e_f_i_l_e
132             Specify a makefile to read instead of the default `_m_a_k_e_f_i_l_e'.  If
133             _m_a_k_e_f_i_l_e is `--', standard input is read.  Multiple makefiles may
134             be specified, and are read in the order specified.
135
136     --II _d_i_r_e_c_t_o_r_y
137             Specify a directory in which to search for makefiles and included
138             makefiles.  The system makefile directory (or directories, see
139             the --mm option) is automatically included as part of this list.
140
141     --ii      Ignore non-zero exit of shell commands in the makefile.  Equiva-
142             lent to specifying `--' before each command line in the makefile.
143
144     --JJ _p_r_i_v_a_t_e
145             This option should _n_o_t be specified by the user.
146
147             When the _j option is in use in a recursive build, this option is
148             passed by a make to child makes to allow all the make processes
149             in the build to cooperate to avoid overloading the system.
150
151     --jj _m_a_x___j_o_b_s
152             Specify the maximum number of jobs that bbmmaakkee may have running at
153             any one time.  The value is saved in _._M_A_K_E_._J_O_B_S.  Turns compati-
154             bility mode off, unless the _B flag is also specified.  When com-
155             patibility mode is off, all commands associated with a target are
156             executed in a single shell invocation as opposed to the tradi-
157             tional one shell invocation per line.  This can break traditional
158             scripts which change directories on each command invocation and
159             then expect to start with a fresh environment on the next line.
160             It is more efficient to correct the scripts rather than turn
161             backwards compatibility on.
162
163     --kk      Continue processing after errors are encountered, but only on
164             those targets that do not depend on the target whose creation
165             caused the error.
166
167     --mm _d_i_r_e_c_t_o_r_y
168             Specify a directory in which to search for sys.mk and makefiles
169             included via the <_f_i_l_e>-style include statement.  The --mm option
170             can be used multiple times to form a search path.  This path will
171             override the default system include path: /usr/share/mk.  Fur-
172             thermore the system include path will be appended to the search
173             path used for "_f_i_l_e"-style include statements (see the --II
174             option).
175
176             If a file or directory name in the --mm argument (or the
177             MAKESYSPATH environment variable) starts with the string ".../"
178             then bbmmaakkee will search for the specified file or directory named
179             in the remaining part of the argument string.  The search starts
180             with the current directory of the Makefile and then works upward
181             towards the root of the file system.  If the search is success-
182             ful, then the resulting directory replaces the ".../" specifica-
183             tion in the --mm argument.  If used, this feature allows bbmmaakkee to
184             easily search in the current source tree for customized sys.mk
185             files (e.g., by using ".../mk/sys.mk" as an argument).
186
187     --nn      Display the commands that would have been executed, but do not
188             actually execute them unless the target depends on the .MAKE spe-
189             cial source (see below).
190
191     --NN      Display the commands which would have been executed, but do not
192             actually execute any of them; useful for debugging top-level
193             makefiles without descending into subdirectories.
194
195     --qq      Do not execute any commands, but exit 0 if the specified targets
196             are up-to-date and 1, otherwise.
197
198     --rr      Do not use the built-in rules specified in the system makefile.
199
200     --ss      Do not echo any commands as they are executed.  Equivalent to
201             specifying `@@' before each command line in the makefile.
202
203     --TT _t_r_a_c_e_f_i_l_e
204             When used with the --jj flag, append a trace record to _t_r_a_c_e_f_i_l_e
205             for each job started and completed.
206
207     --tt      Rather than re-building a target as specified in the makefile,
208             create it or update its modification time to make it appear up-
209             to-date.
210
211     --VV _v_a_r_i_a_b_l_e
212             Print bbmmaakkee's idea of the value of _v_a_r_i_a_b_l_e, in the global con-
213             text.  Do not build any targets.  Multiple instances of this
214             option may be specified; the variables will be printed one per
215             line, with a blank line for each null or undefined variable.  If
216             _v_a_r_i_a_b_l_e contains a `$' then the value will be expanded before
217             printing.
218
219     --WW      Treat any warnings during makefile parsing as errors.
220
221     --ww      Print entering and leaving directory messages, pre and post pro-
222             cessing.
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 one or more lines of shell com-
277     mands, normally used to create the target.  Each of the lines in this
278     script _m_u_s_t be preceded by a tab.  (For historical reasons, spaces are
279     not accepted.)  While targets can appear in many dependency lines if
280     desired, by default only one of these rules may be followed by a creation
281     script.  If the `::::' operator is used, however, all rules may include
282     scripts and the scripts are executed in the order found.
283
284     Each line is treated as a separate shell command, unless the end of line
285     is escaped with a backslash (`\') in which case that line and the next
286     are combined.  If the first characters of the command are any combination
287     of `@@', `++', or `--', the command is treated specially.  A `@@' causes the
288     command not to be echoed before it is executed.  A `++' causes the command
289     to be executed even when --nn is given.  This is similar to the effect of
290     the .MAKE special source, except that the effect can be limited to a sin-
291     gle line of a script.  A `--' in compatibility mode causes any non-zero
292     exit status of the command line to be ignored.
293
294     When bbmmaakkee is run in jobs mode with --jj _m_a_x___j_o_b_s, the entire script for
295     the target is fed to a single instance of the shell.  In compatibility
296     (non-jobs) mode, each command is run in a separate process.  If the com-
297     mand contains any shell meta characters (`#=|^(){};&<>*?[]:$`\\n') it
298     will be passed to the shell; otherwise bbmmaakkee will attempt direct execu-
299     tion.  If a line starts with `--' and the shell has ErrCtl enabled then
300     failure of the command line will be ignored as in compatibility mode.
301     Otherwise `--' affects the entire job; the script will stop at the first
302     command line that fails, but the target will not be deemed to have
303     failed.
304
305     Makefiles should be written so that the mode of bbmmaakkee operation does not
306     change their behavior.  For example, any command which needs to use
307     ``cd'' or ``chdir'' without potentially changing the directory for subse-
308     quent commands should be put in parentheses so it executes in a subshell.
309     To force the use of one shell, escape the line breaks so as to make the
310     whole script one command.  For example:
311
312           avoid-chdir-side-effects:
313                   @echo Building $@ in `pwd`
314                   @(cd ${.CURDIR} && ${MAKE} $@)
315                   @echo Back in `pwd`
316
317           ensure-one-shell-regardless-of-mode:
318                   @echo Building $@ in `pwd`; \
319                   (cd ${.CURDIR} && ${MAKE} $@); \
320                   echo Back in `pwd`
321
322     Since bbmmaakkee will chdir(2) to `_._O_B_J_D_I_R' before executing any targets, each
323     child process starts with that as its current working directory.
324
325VVAARRIIAABBLLEE AASSSSIIGGNNMMEENNTTSS
326     Variables in make are much like variables in the shell, and, by tradi-
327     tion, consist of all upper-case letters.
328
329   VVaarriiaabbllee aassssiiggnnmmeenntt mmooddiiffiieerrss
330     The five operators that can be used to assign values to variables are as
331     follows:
332
333     ==       Assign the value to the variable.  Any previous value is overrid-
334             den.
335
336     ++==      Append the value to the current value of the variable.
337
338     ??==      Assign the value to the variable if it is not already defined.
339
340     ::==      Assign with expansion, i.e. expand the value before assigning it
341             to the variable.  Normally, expansion is not done until the vari-
342             able is referenced.  _N_O_T_E: References to undefined variables are
343             _n_o_t expanded.  This can cause problems when variable modifiers
344             are used.
345
346     !!==      Expand the value and pass it to the shell for execution and
347             assign the result to the variable.  Any newlines in the result
348             are replaced with spaces.
349
350     Any white-space before the assigned _v_a_l_u_e is removed; if the value is
351     being appended, a single space is inserted between the previous contents
352     of the variable and the appended value.
353
354     Variables are expanded by surrounding the variable name with either curly
355     braces (`{}') or parentheses (`()') and preceding it with a dollar sign
356     (`$').  If the variable name contains only a single letter, the surround-
357     ing braces or parentheses are not required.  This shorter form is not
358     recommended.
359
360     If the variable name contains a dollar, then the name itself is expanded
361     first.  This allows almost arbitrary variable names, however names con-
362     taining dollar, braces, parenthesis, or whitespace are really best
363     avoided!
364
365     If the result of expanding a variable contains a dollar sign (`$') the
366     string is expanded again.
367
368     Variable substitution occurs at three distinct times, depending on where
369     the variable is being used.
370
371     1.   Variables in dependency lines are expanded as the line is read.
372
373     2.   Variables in shell commands are expanded when the shell command is
374          executed.
375
376     3.   ``.for'' loop index variables are expanded on each loop iteration.
377          Note that other variables are not expanded inside loops so the fol-
378          lowing example code:
379
380
381                .for i in 1 2 3
382                a+=     ${i}
383                j=      ${i}
384                b+=     ${j}
385                .endfor
386
387                all:
388                        @echo ${a}
389                        @echo ${b}
390
391          will print:
392
393                1 2 3
394                3 3 3
395
396          Because while ${a} contains ``1 2 3'' after the loop is executed,
397          ${b} contains ``${j} ${j} ${j}'' which expands to ``3 3 3'' since
398          after the loop completes ${j} contains ``3''.
399
400   VVaarriiaabbllee ccllaasssseess
401     The four different classes of variables (in order of increasing prece-
402     dence) are:
403
404     Environment variables
405             Variables defined as part of bbmmaakkee's environment.
406
407     Global variables
408             Variables defined in the makefile or in included makefiles.
409
410     Command line variables
411             Variables defined as part of the command line.
412
413     Local variables
414             Variables that are defined specific to a certain target.
415
416     Local variables are all built in and their values vary magically from
417     target to target.  It is not currently possible to define new local vari-
418     ables.  The seven local variables are as follows:
419
420           _._A_L_L_S_R_C   The list of all sources for this target; also known as
421                     `_>'.
422
423           _._A_R_C_H_I_V_E  The name of the archive file; also known as `_!'.
424
425           _._I_M_P_S_R_C   In suffix-transformation rules, the name/path of the
426                     source from which the target is to be transformed (the
427                     ``implied'' source); also known as `_<'.  It is not
428                     defined in explicit rules.
429
430           _._M_E_M_B_E_R   The name of the archive member; also known as `_%'.
431
432           _._O_O_D_A_T_E   The list of sources for this target that were deemed out-
433                     of-date; also known as `_?'.
434
435           _._P_R_E_F_I_X   The file prefix of the target, containing only the file
436                     portion, no suffix or preceding directory components;
437                     also known as `_*'.  The suffix must be one of the known
438                     suffixes declared with ..SSUUFFFFIIXXEESS or it will not be recog-
439                     nized.
440
441           _._T_A_R_G_E_T   The name of the target; also known as `_@'.  For compati-
442                     bility with other makes this is an alias for ..AARRCCHHIIVVEE in
443                     archive member rules.
444
445     The shorter forms (`_>', `_!', `_<', `_%', `_?', `_*', and `_@') are permitted
446     for backward compatibility with historical makefiles and legacy POSIX
447     make and are not recommended.
448
449     Variants of these variables with the punctuation followed immediately by
450     `D' or `F', e.g.  `_$_(_@_D_)', are legacy forms equivalent to using the `:H'
451     and `:T' modifiers.  These forms are accepted for compatibility with AT&T
452     System V UNIX makefiles and POSIX but are not recommended.
453
454     Four of the local variables may be used in sources on dependency lines
455     because they expand to the proper value for each target on the line.
456     These variables are `_._T_A_R_G_E_T', `_._P_R_E_F_I_X', `_._A_R_C_H_I_V_E', and `_._M_E_M_B_E_R'.
457
458   AAddddiittiioonnaall bbuuiilltt--iinn vvaarriiaabblleess
459     In addition, bbmmaakkee sets or knows about the following variables:
460
461     _$               A single dollar sign `$', i.e.  `$$' expands to a single
462                     dollar sign.
463
464     _._A_L_L_T_A_R_G_E_T_S     The list of all targets encountered in the Makefile.  If
465                     evaluated during Makefile parsing, lists only those tar-
466                     gets encountered thus far.
467
468     _._C_U_R_D_I_R         A path to the directory where bbmmaakkee was executed.  Refer
469                     to the description of `PWD' for more details.
470
471     _._I_N_C_L_U_D_E_D_F_R_O_M_D_I_R
472                     The directory of the file this Makefile was included
473                     from.
474
475     _._I_N_C_L_U_D_E_D_F_R_O_M_F_I_L_E
476                     The filename of the file this Makefile was included from.
477
478     MAKE            The name that bbmmaakkee was executed with (_a_r_g_v_[_0_]).  For
479                     compatibility bbmmaakkee also sets _._M_A_K_E with the same value.
480                     The preferred variable to use is the environment variable
481                     MAKE because it is more compatible with other versions of
482                     bbmmaakkee and cannot be confused with the special target with
483                     the same name.
484
485     _._M_A_K_E_._D_E_P_E_N_D_F_I_L_E
486                     Names the makefile (default `_._d_e_p_e_n_d') from which gener-
487                     ated dependencies are read.
488
489     _._M_A_K_E_._E_X_P_A_N_D___V_A_R_I_A_B_L_E_S
490                     A boolean that controls the default behavior of the --VV
491                     option.
492
493     _._M_A_K_E_._E_X_P_O_R_T_E_D  The list of variables exported by bbmmaakkee.
494
495     _._M_A_K_E_._J_O_B_S      The argument to the --jj option.
496
497     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X
498                     If bbmmaakkee is run with _j then output for each target is
499                     prefixed with a token `--- target ---' the first part of
500                     which can be controlled via _._M_A_K_E_._J_O_B_._P_R_E_F_I_X.  If
501                     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X is empty, no token is printed.
502                     For example:
503                     .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
504                     would produce tokens like `---make[1234] target ---' mak-
505                     ing it easier to track the degree of parallelism being
506                     achieved.
507
508     MAKEFLAGS       The environment variable `MAKEFLAGS' may contain anything
509                     that may be specified on bbmmaakkee's command line.  Anything
510                     specified on bbmmaakkee's command line is appended to the
511                     `MAKEFLAGS' variable which is then entered into the envi-
512                     ronment for all programs which bbmmaakkee executes.
513
514     _._M_A_K_E_._L_E_V_E_L     The recursion depth of bbmmaakkee.  The initial instance of
515                     bbmmaakkee will be 0, and an incremented value is put into the
516                     environment to be seen by the next generation.  This
517                     allows tests like: .if ${.MAKE.LEVEL} == 0 to protect
518                     things which should only be evaluated in the initial
519                     instance of bbmmaakkee.
520
521     _._M_A_K_E_._M_A_K_E_F_I_L_E___P_R_E_F_E_R_E_N_C_E
522                     The ordered list of makefile names (default `_m_a_k_e_f_i_l_e',
523                     `_M_a_k_e_f_i_l_e') that bbmmaakkee will look for.
524
525     _._M_A_K_E_._M_A_K_E_F_I_L_E_S
526                     The list of makefiles read by bbmmaakkee, which is useful for
527                     tracking dependencies.  Each makefile is recorded only
528                     once, regardless of the number of times read.
529
530     _._M_A_K_E_._M_O_D_E      Processed after reading all makefiles.  Can affect the
531                     mode that bbmmaakkee runs in.  It can contain a number of key-
532                     words:
533
534                     _c_o_m_p_a_t      Like --BB, puts bbmmaakkee into "compat" mode.
535
536                     _m_e_t_a        Puts bbmmaakkee into "meta" mode, where meta files
537                                 are created for each target to capture the
538                                 command run, the output generated and if
539                                 filemon(4) is available, the system calls
540                                 which are of interest to bbmmaakkee.  The captured
541                                 output can be very useful when diagnosing
542                                 errors.
543
544                     _c_u_r_d_i_r_O_k_= _b_f Normally bbmmaakkee will not create .meta files
545                                 in `_._C_U_R_D_I_R'.  This can be overridden by set-
546                                 ting _b_f to a value which represents True.
547
548                     _e_n_v         For debugging, it can be useful to include
549                                 the environment in the .meta file.
550
551                     _v_e_r_b_o_s_e     If in "meta" mode, print a clue about the
552                                 target being built.  This is useful if the
553                                 build is otherwise running silently.  The
554                                 message printed the value of:
555                                 _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X.
556
557                     _i_g_n_o_r_e_-_c_m_d  Some makefiles have commands which are simply
558                                 not stable.  This keyword causes them to be
559                                 ignored for determining whether a target is
560                                 out of date in "meta" mode.  See also
561                                 ..NNOOMMEETTAA__CCMMPP.
562
563                     _s_i_l_e_n_t_= _b_f  If _b_f is True, when a .meta file is created,
564                                 mark the target ..SSIILLEENNTT.
565
566     _._M_A_K_E_._M_E_T_A_._B_A_I_L_I_W_I_C_K
567                     In "meta" mode, provides a list of prefixes which match
568                     the directories controlled by bbmmaakkee.  If a file that was
569                     generated outside of _._O_B_J_D_I_R but within said bailiwick is
570                     missing, the current target is considered out-of-date.
571
572     _._M_A_K_E_._M_E_T_A_._C_R_E_A_T_E_D
573                     In "meta" mode, this variable contains a list of all the
574                     meta files updated.  If not empty, it can be used to
575                     trigger processing of _._M_A_K_E_._M_E_T_A_._F_I_L_E_S.
576
577     _._M_A_K_E_._M_E_T_A_._F_I_L_E_S
578                     In "meta" mode, this variable contains a list of all the
579                     meta files used (updated or not).  This list can be used
580                     to process the meta files to extract dependency informa-
581                     tion.
582
583     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___P_A_T_H_S
584                     Provides a list of path prefixes that should be ignored;
585                     because the contents are expected to change over time.
586                     The default list includes: `_/_d_e_v _/_e_t_c _/_p_r_o_c _/_t_m_p _/_v_a_r_/_r_u_n
587                     _/_v_a_r_/_t_m_p'
588
589     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___P_A_T_T_E_R_N_S
590                     Provides a list of patterns to match against pathnames.
591                     Ignore any that match.
592
593     _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X
594                     Defines the message printed for each meta file updated in
595                     "meta verbose" mode.  The default value is:
596                           Building ${.TARGET:H:tA}/${.TARGET:T}
597
598     _._M_A_K_E_O_V_E_R_R_I_D_E_S  This variable is used to record the names of variables
599                     assigned to on the command line, so that they may be
600                     exported as part of `MAKEFLAGS'.  This behavior can be
601                     disabled by assigning an empty value to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'
602                     within a makefile.  Extra variables can be exported from
603                     a makefile by appending their names to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'.
604                     `MAKEFLAGS' is re-exported whenever `_._M_A_K_E_O_V_E_R_R_I_D_E_S' is
605                     modified.
606
607     _._M_A_K_E_._P_A_T_H___F_I_L_E_M_O_N
608                     If bbmmaakkee was built with filemon(4) support, this is set
609                     to the path of the device node.  This allows makefiles to
610                     test for this support.
611
612     _._M_A_K_E_._P_I_D       The process-id of bbmmaakkee.
613
614     _._M_A_K_E_._P_P_I_D      The parent process-id of bbmmaakkee.
615
616     _._M_A_K_E_._S_A_V_E___D_O_L_L_A_R_S
617                     value should be a boolean that controls whether `$$' are
618                     preserved when doing `:=' assignments.  The default is
619                     false, for backwards compatibility.  Set to true for com-
620                     patability with other makes.  If set to false, `$$'
621                     becomes `$' per normal evaluation rules.
622
623     _M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R
624                     When bbmmaakkee stops due to an error, it prints its name and
625                     the value of `_._C_U_R_D_I_R' as well as the value of any vari-
626                     ables named in `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R'.
627
628     _._n_e_w_l_i_n_e        This variable is simply assigned a newline character as
629                     its value.  This allows expansions using the ::@@ modifier
630                     to put a newline between iterations of the loop rather
631                     than a space.  For example, the printing of
632                     `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R' could be done as
633                     ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
634
635     _._O_B_J_D_I_R         A path to the directory where the targets are built.  Its
636                     value is determined by trying to chdir(2) to the follow-
637                     ing directories in order and using the first match:
638
639                     1.   ${MAKEOBJDIRPREFIX}${.CURDIR}
640
641                          (Only if `MAKEOBJDIRPREFIX' is set in the environ-
642                          ment or on the command line.)
643
644                     2.   ${MAKEOBJDIR}
645
646                          (Only if `MAKEOBJDIR' is set in the environment or
647                          on the command line.)
648
649                     3.   ${.CURDIR}_/_o_b_j_.${MACHINE}
650
651                     4.   ${.CURDIR}_/_o_b_j
652
653                     5.   _/_u_s_r_/_o_b_j_/${.CURDIR}
654
655                     6.   ${.CURDIR}
656
657                     Variable expansion is performed on the value before it's
658                     used, so expressions such as
659                           ${.CURDIR:S,^/usr/src,/var/obj,}
660                     may be used.  This is especially useful with
661                     `MAKEOBJDIR'.
662
663                     `_._O_B_J_D_I_R' may be modified in the makefile via the special
664                     target `..OOBBJJDDIIRR'.  In all cases, bbmmaakkee will chdir(2) to
665                     the specified directory if it exists, and set `_._O_B_J_D_I_R'
666                     and `PWD' to that directory before executing any targets.
667
668     _._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
669                     parsed.
670
671     _._P_A_R_S_E_F_I_L_E      The basename of the current `_M_a_k_e_f_i_l_e' being parsed.
672                     This variable and `_._P_A_R_S_E_D_I_R' are both set only while the
673                     `_M_a_k_e_f_i_l_e_s' are being parsed.  If you want to retain
674                     their current values, assign them to a variable using
675                     assignment with expansion: (`::==').
676
677     _._P_A_T_H           A variable that represents the list of directories that
678                     bbmmaakkee will search for files.  The search list should be
679                     updated using the target `_._P_A_T_H' rather than the vari-
680                     able.
681
682     PWD             Alternate path to the current directory.  bbmmaakkee normally
683                     sets `_._C_U_R_D_I_R' to the canonical path given by getcwd(3).
684                     However, if the environment variable `PWD' is set and
685                     gives a path to the current directory, then bbmmaakkee sets
686                     `_._C_U_R_D_I_R' to the value of `PWD' instead.  This behavior
687                     is disabled if `MAKEOBJDIRPREFIX' is set or `MAKEOBJDIR'
688                     contains a variable transform.  `PWD' is set to the value
689                     of `_._O_B_J_D_I_R' for all programs which bbmmaakkee executes.
690
691     .TARGETS        The list of targets explicitly specified on the command
692                     line, if any.
693
694     VPATH           Colon-separated (``:'') lists of directories that bbmmaakkee
695                     will search for files.  The variable is supported for
696                     compatibility with old make programs only, use `_._P_A_T_H'
697                     instead.
698
699   VVaarriiaabbllee mmooddiiffiieerrss
700     Variable expansion may be modified to select or modify each word of the
701     variable (where a ``word'' is white-space delimited sequence of charac-
702     ters).  The general format of a variable expansion is as follows:
703
704           ${variable[:modifier[:...]]}
705
706     Each modifier begins with a colon, which may be escaped with a backslash
707     (`\').
708
709     A set of modifiers can be specified via a variable, as follows:
710
711           modifier_variable=modifier[:...]
712           ${variable:${modifier_variable}[:...]}
713
714     In this case the first modifier in the modifier_variable does not start
715     with a colon, since that must appear in the referencing variable.  If any
716     of the modifiers in the modifier_variable contain a dollar sign (`$'),
717     these must be doubled to avoid early expansion.
718
719     The supported modifiers are:
720
721     ::EE   Replaces each word in the variable with its suffix.
722
723     ::HH   Replaces each word in the variable with everything but the last com-
724          ponent.
725
726     ::MM_p_a_t_t_e_r_n
727          Select only those words that match _p_a_t_t_e_r_n.  The standard shell
728          wildcard characters (`*', `?', and `[]') may be used.  The wildcard
729          characters may be escaped with a backslash (`\').  As a consequence
730          of the way values are split into words, matched, and then joined, a
731          construct like
732                ${VAR:M*}
733          will normalize the inter-word spacing, removing all leading and
734          trailing space, and converting multiple consecutive spaces to single
735          spaces.
736
737     ::NN_p_a_t_t_e_r_n
738          This is identical to `::MM', but selects all words which do not match
739          _p_a_t_t_e_r_n.
740
741     ::OO   Order every word in variable alphabetically.  To sort words in
742          reverse order use the `::OO::[[--11....11]]' combination of modifiers.
743
744     ::OOxx  Randomize words in variable.  The results will be different each
745          time you are referring to the modified variable; use the assignment
746          with expansion (`::==') to prevent such behavior.  For example,
747
748                LIST=                   uno due tre quattro
749                RANDOM_LIST=            ${LIST:Ox}
750                STATIC_RANDOM_LIST:=    ${LIST:Ox}
751
752                all:
753                        @echo "${RANDOM_LIST}"
754                        @echo "${RANDOM_LIST}"
755                        @echo "${STATIC_RANDOM_LIST}"
756                        @echo "${STATIC_RANDOM_LIST}"
757          may produce output similar to:
758
759                quattro due tre uno
760                tre due quattro uno
761                due uno quattro tre
762                due uno quattro tre
763
764     ::QQ   Quotes every shell meta-character in the variable, so that it can be
765          passed safely through recursive invocations of bbmmaakkee.
766
767     ::RR   Replaces each word in the variable with everything but its suffix.
768
769     ::ggmmttiimmee
770          The value is a format string for strftime(3), using the current
771          gmtime(3).
772
773     ::hhaasshh
774          Compute a 32-bit hash of the value and encode it as hex digits.
775
776     ::llooccaallttiimmee
777          The value is a format string for strftime(3), using the current
778          localtime(3).
779
780     ::ttAA  Attempt to convert variable to an absolute path using realpath(3),
781          if that fails, the value is unchanged.
782
783     ::ttll  Converts variable to lower-case letters.
784
785     ::ttss_c
786          Words in the variable are normally separated by a space on expan-
787          sion.  This modifier sets the separator to the character _c.  If _c is
788          omitted, then no separator is used.  The common escapes (including
789          octal numeric codes), work as expected.
790
791     ::ttuu  Converts variable to upper-case letters.
792
793     ::ttWW  Causes the value to be treated as a single word (possibly containing
794          embedded white space).  See also `::[[**]]'.
795
796     ::ttww  Causes the value to be treated as a sequence of words delimited by
797          white space.  See also `::[[@@]]'.
798
799     ::SS/_o_l_d___s_t_r_i_n_g/_n_e_w___s_t_r_i_n_g/[11ggWW]
800          Modify the first occurrence of _o_l_d___s_t_r_i_n_g in the variable's value,
801          replacing it with _n_e_w___s_t_r_i_n_g.  If a `g' is appended to the last
802          slash of the pattern, all occurrences in each word are replaced.  If
803          a `1' is appended to the last slash of the pattern, only the first
804          word is affected.  If a `W' is appended to the last slash of the
805          pattern, then the value is treated as a single word (possibly con-
806          taining embedded white space).  If _o_l_d___s_t_r_i_n_g begins with a caret
807          (`^'), _o_l_d___s_t_r_i_n_g is anchored at the beginning of each word.  If
808          _o_l_d___s_t_r_i_n_g ends with a dollar sign (`$'), it is anchored at the end
809          of each word.  Inside _n_e_w___s_t_r_i_n_g, an ampersand (`&') is replaced by
810          _o_l_d___s_t_r_i_n_g (without any `^' or `$').  Any character may be used as a
811          delimiter for the parts of the modifier string.  The anchoring,
812          ampersand and delimiter characters may be escaped with a backslash
813          (`\').
814
815          Variable expansion occurs in the normal fashion inside both
816          _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
817          is used to prevent the expansion of a dollar sign (`$'), not a pre-
818          ceding dollar sign as is usual.
819
820     ::CC/_p_a_t_t_e_r_n/_r_e_p_l_a_c_e_m_e_n_t/[11ggWW]
821          The ::CC modifier is just like the ::SS modifier except that the old and
822          new strings, instead of being simple strings, are an extended regu-
823          lar expression (see regex(3)) string _p_a_t_t_e_r_n and an ed(1)-style
824          string _r_e_p_l_a_c_e_m_e_n_t.  Normally, the first occurrence of the pattern
825          _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.
826          The `1' modifier causes the substitution to apply to at most one
827          word; the `g' modifier causes the substitution to apply to as many
828          instances of the search pattern _p_a_t_t_e_r_n as occur in the word or
829          words it is found in; the `W' modifier causes the value to be
830          treated as a single word (possibly containing embedded white space).
831          Note that `1' and `g' are orthogonal; the former specifies whether
832          multiple words are potentially affected, the latter whether multiple
833          substitutions can potentially occur within each affected word.
834
835          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
836          variable expansion before being parsed as regular expressions.
837
838     ::TT   Replaces each word in the variable with its last component.
839
840     ::uu   Remove adjacent duplicate words (like uniq(1)).
841
842     ::??_t_r_u_e___s_t_r_i_n_g::_f_a_l_s_e___s_t_r_i_n_g
843          If the variable name (not its value), when parsed as a .if condi-
844          tional expression, evaluates to true, return as its value the
845          _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
846          name is used as the expression, :? must be the first modifier after
847          the variable name itself - which will, of course, usually contain
848          variable expansions.  A common error is trying to use expressions
849          like
850                ${NUMBERS:M42:?match:no}
851          which actually tests defined(NUMBERS), to determine is any words
852          match "42" you need to use something like:
853                ${"${NUMBERS:M42}" != "":?match:no}.
854
855     _:_o_l_d___s_t_r_i_n_g_=_n_e_w___s_t_r_i_n_g
856          This is the AT&T System V UNIX style variable substitution.  It must
857          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
858          contain the pattern matching character _% then it is assumed that
859          they are anchored at the end of each word, so only suffixes or
860          entire words may be replaced.  Otherwise _% is the substring of
861          _o_l_d___s_t_r_i_n_g to be replaced in _n_e_w___s_t_r_i_n_g.
862
863          Variable expansion occurs in the normal fashion inside both
864          _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
865          is used to prevent the expansion of a dollar sign (`$'), not a pre-
866          ceding dollar sign as is usual.
867
868     ::@@_t_e_m_p@@_s_t_r_i_n_g@@
869          This is the loop expansion mechanism from the OSF Development Envi-
870          ronment (ODE) make.  Unlike ..ffoorr loops expansion occurs at the time
871          of reference.  Assign _t_e_m_p to each word in the variable and evaluate
872          _s_t_r_i_n_g.  The ODE convention is that _t_e_m_p should start and end with a
873          period.  For example.
874                ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
875
876          However a single character variable is often more readable:
877                ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
878
879     ::UU_n_e_w_v_a_l
880          If the variable is undefined _n_e_w_v_a_l is the value.  If the variable
881          is defined, the existing value is returned.  This is another ODE
882          make feature.  It is handy for setting per-target CFLAGS for
883          instance:
884                ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
885          If a value is only required if the variable is undefined, use:
886                ${VAR:D:Unewval}
887
888     ::DD_n_e_w_v_a_l
889          If the variable is defined _n_e_w_v_a_l is the value.
890
891     ::LL   The name of the variable is the value.
892
893     ::PP   The path of the node which has the same name as the variable is the
894          value.  If no such node exists or its path is null, then the name of
895          the variable is used.  In order for this modifier to work, the name
896          (node) must at least have appeared on the rhs of a dependency.
897
898     ::!!_c_m_d!!
899          The output of running _c_m_d is the value.
900
901     ::sshh  If the variable is non-empty it is run as a command and the output
902          becomes the new value.
903
904     ::::==_s_t_r
905          The variable is assigned the value _s_t_r after substitution.  This
906          modifier and its variations are useful in obscure situations such as
907          wanting to set a variable when shell commands are being parsed.
908          These assignment modifiers always expand to nothing, so if appearing
909          in a rule line by themselves should be preceded with something to
910          keep bbmmaakkee happy.
911
912          The `::::' helps avoid false matches with the AT&T System V UNIX style
913          ::== modifier and since substitution always occurs the ::::== form is
914          vaguely appropriate.
915
916     ::::??==_s_t_r
917          As for ::::== but only if the variable does not already have a value.
918
919     ::::++==_s_t_r
920          Append _s_t_r to the variable.
921
922     ::::!!==_c_m_d
923          Assign the output of _c_m_d to the variable.
924
925     ::[[_r_a_n_g_e]]
926          Selects one or more words from the value, or performs other opera-
927          tions related to the way in which the value is divided into words.
928
929          Ordinarily, a value is treated as a sequence of words delimited by
930          white space.  Some modifiers suppress this behavior, causing a value
931          to be treated as a single word (possibly containing embedded white
932          space).  An empty value, or a value that consists entirely of white-
933          space, is treated as a single word.  For the purposes of the `::[[]]'
934          modifier, the words are indexed both forwards using positive inte-
935          gers (where index 1 represents the first word), and backwards using
936          negative integers (where index -1 represents the last word).
937
938          The _r_a_n_g_e is subjected to variable expansion, and the expanded
939          result is then interpreted as follows:
940
941          _i_n_d_e_x  Selects a single word from the value.
942
943          _s_t_a_r_t...._e_n_d
944                 Selects all words from _s_t_a_r_t to _e_n_d, inclusive.  For example,
945                 `::[[22....--11]]' selects all words from the second word to the last
946                 word.  If _s_t_a_r_t is greater than _e_n_d, then the words are out-
947                 put in reverse order.  For example, `::[[--11....11]]' selects all
948                 the words from last to first.
949
950          **      Causes subsequent modifiers to treat the value as a single
951                 word (possibly containing embedded white space).  Analogous
952                 to the effect of "$*" in Bourne shell.
953
954          0      Means the same as `::[[**]]'.
955
956          @@      Causes subsequent modifiers to treat the value as a sequence
957                 of words delimited by white space.  Analogous to the effect
958                 of "$@" in Bourne shell.
959
960          ##      Returns the number of words in the value.
961
962IINNCCLLUUDDEE SSTTAATTEEMMEENNTTSS,, CCOONNDDIITTIIOONNAALLSS AANNDD FFOORR LLOOOOPPSS
963     Makefile inclusion, conditional structures and for loops  reminiscent of
964     the C programming language are provided in bbmmaakkee.  All such structures
965     are identified by a line beginning with a single dot (`.') character.
966     Files are included with either ..iinncclluuddee <_f_i_l_e> or ..iinncclluuddee "_f_i_l_e".  Vari-
967     ables between the angle brackets or double quotes are expanded to form
968     the file name.  If angle brackets are used, the included makefile is
969     expected to be in the system makefile directory.  If double quotes are
970     used, the including makefile's directory and any directories specified
971     using the --II option are searched before the system makefile directory.
972     For compatibility with other versions of bbmmaakkee `include file ...' is also
973     accepted.
974
975     If the include statement is written as ..--iinncclluuddee or as ..ssiinncclluuddee then
976     errors locating and/or opening include files are ignored.
977
978     If the include statement is written as ..ddiinncclluuddee not only are errors
979     locating and/or opening include files ignored, but stale dependencies
980     within the included file will be ignored just like _._M_A_K_E_._D_E_P_E_N_D_F_I_L_E.
981
982     Conditional expressions are also preceded by a single dot as the first
983     character of a line.  The possible conditionals are as follows:
984
985     ..eerrrroorr _m_e_s_s_a_g_e
986             The message is printed along with the name of the makefile and
987             line number, then bbmmaakkee will exit.
988
989     ..eexxppoorrtt _v_a_r_i_a_b_l_e _._._.
990             Export the specified global variable.  If no variable list is
991             provided, all globals are exported except for internal variables
992             (those that start with `.').  This is not affected by the --XX
993             flag, so should be used with caution.  For compatibility with
994             other bbmmaakkee programs `export variable=value' is also accepted.
995
996             Appending a variable name to _._M_A_K_E_._E_X_P_O_R_T_E_D is equivalent to
997             exporting a variable.
998
999     ..eexxppoorrtt--eennvv _v_a_r_i_a_b_l_e _._._.
1000             The same as `.export', except that the variable is not appended
1001             to _._M_A_K_E_._E_X_P_O_R_T_E_D.  This allows exporting a value to the environ-
1002             ment which is different from that used by bbmmaakkee internally.
1003
1004     ..eexxppoorrtt--lliitteerraall _v_a_r_i_a_b_l_e _._._.
1005             The same as `.export-env', except that variables in the value are
1006             not expanded.
1007
1008     ..iinnffoo _m_e_s_s_a_g_e
1009             The message is printed along with the name of the makefile and
1010             line number.
1011
1012     ..uunnddeeff _v_a_r_i_a_b_l_e
1013             Un-define the specified global variable.  Only global variables
1014             may be un-defined.
1015
1016     ..uunneexxppoorrtt _v_a_r_i_a_b_l_e _._._.
1017             The opposite of `.export'.  The specified global _v_a_r_i_a_b_l_e will be
1018             removed from _._M_A_K_E_._E_X_P_O_R_T_E_D.  If no variable list is provided,
1019             all globals are unexported, and _._M_A_K_E_._E_X_P_O_R_T_E_D deleted.
1020
1021     ..uunneexxppoorrtt--eennvv
1022             Unexport all globals previously exported and clear the environ-
1023             ment inherited from the parent.  This operation will cause a mem-
1024             ory leak of the original environment, so should be used spar-
1025             ingly.  Testing for _._M_A_K_E_._L_E_V_E_L being 0, would make sense.  Also
1026             note that any variables which originated in the parent environ-
1027             ment should be explicitly preserved if desired.  For example:
1028
1029                   .if ${.MAKE.LEVEL} == 0
1030                   PATH := ${PATH}
1031                   .unexport-env
1032                   .export PATH
1033                   .endif
1034
1035             Would result in an environment containing only `PATH', which is
1036             the minimal useful environment.  Actually `.MAKE.LEVEL' will also
1037             be pushed into the new environment.
1038
1039     ..wwaarrnniinngg _m_e_s_s_a_g_e
1040             The message prefixed by `_w_a_r_n_i_n_g_:' is printed along with the name
1041             of the makefile and line number.
1042
1043     ..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 _._._.]
1044             Test the value of an expression.
1045
1046     ..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 _._._.]
1047             Test the value of a variable.
1048
1049     ..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 _._._.]
1050             Test the value of a variable.
1051
1052     ..iiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1053             Test the target being built.
1054
1055     ..iiffnnmmaakkee [!] _t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1056             Test the target being built.
1057
1058     ..eellssee   Reverse the sense of the last conditional.
1059
1060     ..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 _._._.]
1061             A combination of `..eellssee' followed by `..iiff'.
1062
1063     ..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 _._._.]
1064             A combination of `..eellssee' followed by `..iiffddeeff'.
1065
1066     ..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 _._._.]
1067             A combination of `..eellssee' followed by `..iiffnnddeeff'.
1068
1069     ..eelliiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1070             A combination of `..eellssee' followed by `..iiffmmaakkee'.
1071
1072     ..eelliiffnnmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1073             A combination of `..eellssee' followed by `..iiffnnmmaakkee'.
1074
1075     ..eennddiiff  End the body of the conditional.
1076
1077     The _o_p_e_r_a_t_o_r may be any one of the following:
1078
1079     ||||     Logical OR.
1080
1081     &&&&     Logical AND; of higher precedence than ``||''.
1082
1083     As in C, bbmmaakkee will only evaluate a conditional as far as is necessary to
1084     determine its value.  Parentheses may be used to change the order of
1085     evaluation.  The boolean operator `!!' may be used to logically negate an
1086     entire conditional.  It is of higher precedence than `&&&&'.
1087
1088     The value of _e_x_p_r_e_s_s_i_o_n may be any of the following:
1089
1090     ddeeffiinneedd  Takes a variable name as an argument and evaluates to true if
1091              the variable has been defined.
1092
1093     mmaakkee     Takes a target name as an argument and evaluates to true if the
1094              target was specified as part of bbmmaakkee's command line or was
1095              declared the default target (either implicitly or explicitly,
1096              see _._M_A_I_N) before the line containing the conditional.
1097
1098     eemmppttyy    Takes a variable, with possible modifiers, and evaluates to true
1099              if the expansion of the variable would result in an empty
1100              string.
1101
1102     eexxiissttss   Takes a file name as an argument and evaluates to true if the
1103              file exists.  The file is searched for on the system search path
1104              (see _._P_A_T_H).
1105
1106     ttaarrggeett   Takes a target name as an argument and evaluates to true if the
1107              target has been defined.
1108
1109     ccoommmmaannddss
1110              Takes a target name as an argument and evaluates to true if the
1111              target has been defined and has commands associated with it.
1112
1113     _E_x_p_r_e_s_s_i_o_n may also be an arithmetic or string comparison.  Variable
1114     expansion is performed on both sides of the comparison, after which the
1115     integral values are compared.  A value is interpreted as hexadecimal if
1116     it is preceded by 0x, otherwise it is decimal; octal numbers are not sup-
1117     ported.  The standard C relational operators are all supported.  If after
1118     variable expansion, either the left or right hand side of a `====' or `!!=='
1119     operator is not an integral value, then string comparison is performed
1120     between the expanded variables.  If no relational operator is given, it
1121     is assumed that the expanded variable is being compared against 0 or an
1122     empty string in the case of a string comparison.
1123
1124     When bbmmaakkee is evaluating one of these conditional expressions, and it
1125     encounters a (white-space separated) word it doesn't recognize, either
1126     the ``make'' or ``defined'' expression is applied to it, depending on the
1127     form of the conditional.  If the form is `..iiffddeeff', `..iiffnnddeeff', or `..iiff'
1128     the ``defined'' expression is applied.  Similarly, if the form is
1129     `..iiffmmaakkee' or `..iiffnnmmaakkee, tthhee' ``make'' expression is applied.
1130
1131     If the conditional evaluates to true the parsing of the makefile contin-
1132     ues as before.  If it evaluates to false, the following lines are
1133     skipped.  In both cases this continues until a `..eellssee' or `..eennddiiff' is
1134     found.
1135
1136     For loops are typically used to apply a set of rules to a list of files.
1137     The syntax of a for loop is:
1138
1139     ..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
1140     <make-rules>
1141     ..eennddffoorr
1142
1143     After the for eexxpprreessssiioonn is evaluated, it is split into words.  On each
1144     iteration of the loop, one word is taken and assigned to each vvaarriiaabbllee,
1145     in order, and these vvaarriiaabblleess are substituted into the mmaakkee--rruulleess inside
1146     the body of the for loop.  The number of words must come out even; that
1147     is, if there are three iteration variables, the number of words provided
1148     must be a multiple of three.
1149
1150CCOOMMMMEENNTTSS
1151     Comments begin with a hash (`#') character, anywhere but in a shell com-
1152     mand line, and continue to the end of an unescaped new line.
1153
1154SSPPEECCIIAALL SSOOUURRCCEESS ((AATTTTRRIIBBUUTTEESS))
1155     ..EEXXEECC     Target is never out of date, but always execute commands any-
1156               way.
1157
1158     ..IIGGNNOORREE   Ignore any errors from the commands associated with this tar-
1159               get, exactly as if they all were preceded by a dash (`-').
1160
1161     ..MMAADDEE     Mark all sources of this target as being up-to-date.
1162
1163     ..MMAAKKEE     Execute the commands associated with this target even if the --nn
1164               or --tt options were specified.  Normally used to mark recursive
1165               bbmmaakkees.
1166
1167     ..MMEETTAA     Create a meta file for the target, even if it is flagged as
1168               ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL.  Usage in conjunction with ..MMAAKKEE is
1169               the most likely case.  In "meta" mode, the target is out-of-
1170               date if the meta file is missing.
1171
1172     ..NNOOMMEETTAA   Do not create a meta file for the target.  Meta files are also
1173               not created for ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL targets.
1174
1175     ..NNOOMMEETTAA__CCMMPP
1176               Ignore differences in commands when deciding if target is out
1177               of date.  This is useful if the command contains a value which
1178               always changes.  If the number of commands change, though, the
1179               target will still be out of date.  The same effect applies to
1180               any command line that uses the variable _._O_O_D_A_T_E, which can be
1181               used for that purpose even when not otherwise needed or
1182               desired:
1183
1184
1185                     skip-compare-for-some:
1186                             @echo this will be compared
1187                             @echo this will not ${.OODATE:M.NOMETA_CMP}
1188                             @echo this will also be compared
1189
1190               The ::MM pattern suppresses any expansion of the unwanted vari-
1191               able.
1192
1193     ..NNOOPPAATTHH   Do not search for the target in the directories specified by
1194               ..PPAATTHH.
1195
1196     ..NNOOTTMMAAIINN  Normally bbmmaakkee selects the first target it encounters as the
1197               default target to be built if no target was specified.  This
1198               source prevents this target from being selected.
1199
1200     ..OOPPTTIIOONNAALL
1201               If a target is marked with this attribute and bbmmaakkee can't fig-
1202               ure out how to create it, it will ignore this fact and assume
1203               the file isn't needed or already exists.
1204
1205     ..PPHHOONNYY    The target does not correspond to an actual file; it is always
1206               considered to be out of date, and will not be created with the
1207               --tt option.  Suffix-transformation rules are not applied to
1208               ..PPHHOONNYY targets.
1209
1210     ..PPRREECCIIOOUUSS
1211               When bbmmaakkee is interrupted, it normally removes any partially
1212               made targets.  This source prevents the target from being
1213               removed.
1214
1215     ..RREECCUURRSSIIVVEE
1216               Synonym for ..MMAAKKEE.
1217
1218     ..SSIILLEENNTT   Do not echo any of the commands associated with this target,
1219               exactly as if they all were preceded by an at sign (`@').
1220
1221     ..UUSSEE      Turn the target into bbmmaakkee's version of a macro.  When the tar-
1222               get is used as a source for another target, the other target
1223               acquires the commands, sources, and attributes (except for
1224               ..UUSSEE) of the source.  If the target already has commands, the
1225               ..UUSSEE target's commands are appended to them.
1226
1227     ..UUSSEEBBEEFFOORREE
1228               Exactly like ..UUSSEE, but prepend the ..UUSSEEBBEEFFOORREE target commands
1229               to the target.
1230
1231     ..WWAAIITT     If ..WWAAIITT appears in a dependency line, the sources that precede
1232               it are made before the sources that succeed it in the line.
1233               Since the dependents of files are not made until the file
1234               itself could be made, this also stops the dependents being
1235               built unless they are needed for another branch of the depen-
1236               dency tree.  So given:
1237
1238               x: a .WAIT b
1239                       echo x
1240               a:
1241                       echo a
1242               b: b1
1243                       echo b
1244               b1:
1245                       echo b1
1246
1247               the output is always `a', `b1', `b', `x'.
1248               The ordering imposed by ..WWAAIITT is only relevant for parallel
1249               makes.
1250
1251SSPPEECCIIAALL TTAARRGGEETTSS
1252     Special targets may not be included with other targets, i.e. they must be
1253     the only target specified.
1254
1255     ..BBEEGGIINN   Any command lines attached to this target are executed before
1256              anything else is done.
1257
1258     ..DDEEFFAAUULLTT
1259              This is sort of a ..UUSSEE rule for any target (that was used only
1260              as a source) that bbmmaakkee can't figure out any other way to cre-
1261              ate.  Only the shell script is used.  The ..IIMMPPSSRRCC variable of a
1262              target that inherits ..DDEEFFAAUULLTT's commands is set to the target's
1263              own name.
1264
1265     ..EENNDD     Any command lines attached to this target are executed after
1266              everything else is done.
1267
1268     ..EERRRROORR   Any command lines attached to this target are executed when
1269              another target fails.  The ..EERRRROORR__TTAARRGGEETT variable is set to the
1270              target that failed.  See also MMAAKKEE__PPRRIINNTT__VVAARR__OONN__EERRRROORR.
1271
1272     ..IIGGNNOORREE  Mark each of the sources with the ..IIGGNNOORREE attribute.  If no
1273              sources are specified, this is the equivalent of specifying the
1274              --ii option.
1275
1276     ..IINNTTEERRRRUUPPTT
1277              If bbmmaakkee is interrupted, the commands for this target will be
1278              executed.
1279
1280     ..MMAAIINN    If no target is specified when bbmmaakkee is invoked, this target
1281              will be built.
1282
1283     ..MMAAKKEEFFLLAAGGSS
1284              This target provides a way to specify flags for bbmmaakkee when the
1285              makefile is used.  The flags are as if typed to the shell,
1286              though the --ff option will have no effect.
1287
1288     ..NNOOPPAATTHH  Apply the ..NNOOPPAATTHH attribute to any specified sources.
1289
1290     ..NNOOTTPPAARRAALLLLEELL
1291              Disable parallel mode.
1292
1293     ..NNOO__PPAARRAALLLLEELL
1294              Synonym for ..NNOOTTPPAARRAALLLLEELL, for compatibility with other pmake
1295              variants.
1296
1297     ..OOBBJJDDIIRR  The source is a new value for `_._O_B_J_D_I_R'.  If it exists, bbmmaakkee
1298              will chdir(2) to it and update the value of `_._O_B_J_D_I_R'.
1299
1300     ..OORRDDEERR   The named targets are made in sequence.  This ordering does not
1301              add targets to the list of targets to be made.  Since the depen-
1302              dents of a target do not get built until the target itself could
1303              be built, unless `a' is built by another part of the dependency
1304              graph, the following is a dependency loop:
1305
1306              .ORDER: b a
1307              b: a
1308
1309              The ordering imposed by ..OORRDDEERR is only relevant for parallel
1310              makes.
1311
1312     ..PPAATTHH    The sources are directories which are to be searched for files
1313              not found in the current directory.  If no sources are speci-
1314              fied, any previously specified directories are deleted.  If the
1315              source is the special ..DDOOTTLLAASSTT target, then the current working
1316              directory is searched last.
1317
1318     ..PPAATTHH.._s_u_f_f_i_x
1319              Like ..PPAATTHH but applies only to files with a particular suffix.
1320              The suffix must have been previously declared with ..SSUUFFFFIIXXEESS.
1321
1322     ..PPHHOONNYY   Apply the ..PPHHOONNYY attribute to any specified sources.
1323
1324     ..PPRREECCIIOOUUSS
1325              Apply the ..PPRREECCIIOOUUSS attribute to any specified sources.  If no
1326              sources are specified, the ..PPRREECCIIOOUUSS attribute is applied to
1327              every target in the file.
1328
1329     ..SSHHEELLLL   Sets the shell that bbmmaakkee will use to execute commands.  The
1330              sources are a set of _f_i_e_l_d_=_v_a_l_u_e pairs.
1331
1332              _n_a_m_e        This is the minimal specification, used to select
1333                          one of the built-in shell specs; _s_h, _k_s_h, and _c_s_h.
1334
1335              _p_a_t_h        Specifies the path to the shell.
1336
1337              _h_a_s_E_r_r_C_t_l   Indicates whether the shell supports exit on error.
1338
1339              _c_h_e_c_k       The command to turn on error checking.
1340
1341              _i_g_n_o_r_e      The command to disable error checking.
1342
1343              _e_c_h_o        The command to turn on echoing of commands executed.
1344
1345              _q_u_i_e_t       The command to turn off echoing of commands exe-
1346                          cuted.
1347
1348              _f_i_l_t_e_r      The output to filter after issuing the _q_u_i_e_t com-
1349                          mand.  It is typically identical to _q_u_i_e_t.
1350
1351              _e_r_r_F_l_a_g     The flag to pass the shell to enable error checking.
1352
1353              _e_c_h_o_F_l_a_g    The flag to pass the shell to enable command echo-
1354                          ing.
1355
1356              _n_e_w_l_i_n_e     The string literal to pass the shell that results in
1357                          a single newline character when used outside of any
1358                          quoting characters.
1359              Example:
1360
1361              .SHELL: name=ksh path=/bin/ksh hasErrCtl=true \
1362                      check="set -e" ignore="set +e" \
1363                      echo="set -v" quiet="set +v" filter="set +v" \
1364                      echoFlag=v errFlag=e newline="'\n'"
1365
1366     ..SSIILLEENNTT  Apply the ..SSIILLEENNTT attribute to any specified sources.  If no
1367              sources are specified, the ..SSIILLEENNTT attribute is applied to every
1368              command in the file.
1369
1370     ..SSTTAALLEE   This target gets run when a dependency file contains stale
1371              entries, having _._A_L_L_S_R_C set to the name of that dependency file.
1372
1373     ..SSUUFFFFIIXXEESS
1374              Each source specifies a suffix to bbmmaakkee.  If no sources are
1375              specified, any previously specified suffixes are deleted.  It
1376              allows the creation of suffix-transformation rules.
1377
1378              Example:
1379
1380              .SUFFIXES: .o
1381              .c.o:
1382                      cc -o ${.TARGET} -c ${.IMPSRC}
1383
1384EENNVVIIRROONNMMEENNTT
1385     bbmmaakkee uses the following environment variables, if they exist: MACHINE,
1386     MACHINE_ARCH, MAKE, MAKEFLAGS, MAKEOBJDIR, MAKEOBJDIRPREFIX, MAKESYSPATH,
1387     PWD, and TMPDIR.
1388
1389     MAKEOBJDIRPREFIX and MAKEOBJDIR may only be set in the environment or on
1390     the command line to bbmmaakkee and not as makefile variables; see the descrip-
1391     tion of `_._O_B_J_D_I_R' for more details.
1392
1393FFIILLEESS
1394     .depend        list of dependencies
1395     Makefile       list of dependencies
1396     makefile       list of dependencies
1397     sys.mk         system makefile
1398     /usr/share/mk  system makefile directory
1399
1400CCOOMMPPAATTIIBBIILLIITTYY
1401     The basic make syntax is compatible between different versions of make;
1402     however the special variables, variable modifiers and conditionals are
1403     not.
1404
1405   OOllddeerr vveerrssiioonnss
1406     An incomplete list of changes in older versions of bbmmaakkee:
1407
1408     The way that .for loop variables are substituted changed after NetBSD 5.0
1409     so that they still appear to be variable expansions.  In particular this
1410     stops them being treated as syntax, and removes some obscure problems
1411     using them in .if statements.
1412
1413     The way that parallel makes are scheduled changed in NetBSD 4.0 so that
1414     .ORDER and .WAIT apply recursively to the dependent nodes.  The algo-
1415     rithms used may change again in the future.
1416
1417   OOtthheerr mmaakkee ddiiaalleeccttss
1418     Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not sup-
1419     port most of the features of bbmmaakkee as described in this manual.  Most
1420     notably:
1421
1422           ++oo   The ..WWAAIITT and ..OORRDDEERR declarations and most functionality per-
1423               taining to parallelization.  (GNU make supports parallelization
1424               but lacks these features needed to control it effectively.)
1425
1426           ++oo   Directives, including for loops and conditionals and most of
1427               the forms of include files.  (GNU make has its own incompatible
1428               and less powerful syntax for conditionals.)
1429
1430           ++oo   All built-in variables that begin with a dot.
1431
1432           ++oo   Most of the special sources and targets that begin with a dot,
1433               with the notable exception of ..PPHHOONNYY, ..PPRREECCIIOOUUSS, and ..SSUUFFFFIIXXEESS.
1434
1435           ++oo   Variable modifiers, except for the
1436                     :old=new
1437               string substitution, which does not portably support globbing
1438               with `%' and historically only works on declared suffixes.
1439
1440           ++oo   The $$>> variable even in its short form; most makes support this
1441               functionality but its name varies.
1442
1443     Some features are somewhat more portable, such as assignment with ++==, ??==,
1444     and !!==.  The ..PPAATTHH functionality is based on an older feature VVPPAATTHH found
1445     in GNU make and many versions of SVR4 make; however, historically its
1446     behavior is too ill-defined (and too buggy) to rely upon.
1447
1448     The $$@@ and $$<< variables are more or less universally portable, as is the
1449     $$((MMAAKKEE)) variable.  Basic use of suffix rules (for files only in the cur-
1450     rent directory, not trying to chain transformations together, etc.) is
1451     also reasonably portable.
1452
1453SSEEEE AALLSSOO
1454     mkdep(1)
1455
1456HHIISSTTOORRYY
1457     bbmmaakkee is derived from NetBSD make(1).  It uses autoconf to facilitate
1458     portability to other platforms.
1459
1460     A make command appeared in Version 7 AT&T UNIX.  This make implementation
1461     is based on Adam De Boor's pmake program which was written for Sprite at
1462     Berkeley.  It was designed to be a parallel distributed make running jobs
1463     on different machines using a daemon called ``customs''.
1464
1465     Historically the target/dependency ``FRC'' has been used to FoRCe
1466     rebuilding (since the target/dependency does not exist... unless someone
1467     creates an ``FRC'' file).
1468
1469BBUUGGSS
1470     The make syntax is difficult to parse without actually acting of the
1471     data.  For instance finding the end of a variable use should involve
1472     scanning each the modifiers using the correct terminator for each field.
1473     In many places make just counts {} and () in order to find the end of a
1474     variable expansion.
1475
1476     There is no way of escaping a space character in a filename.
1477
1478NetBSD 5.1                       May 10, 2016                       NetBSD 5.1
1479