xref: /freebsd/contrib/bmake/bmake.cat1 (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
1BMAKE(1)                NetBSD General Commands Manual                BMAKE(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] [--vv _v_a_r_i_a_b_l_e]
10           [_v_a_r_i_a_b_l_e_=_v_a_l_u_e] [_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                     overriding the default behavior set via
123                     _._M_A_K_E_._E_X_P_A_N_D___V_A_R_I_A_B_L_E_S.
124
125             _v       Print debugging information about variable assignment.
126
127             _x       Run shell commands with --xx so the actual commands are
128                     printed as they are executed.
129
130     --ee      Specify that environment variables override macro assignments
131             within makefiles.
132
133     --ff _m_a_k_e_f_i_l_e
134             Specify a makefile to read instead of the default `_m_a_k_e_f_i_l_e'.  If
135             _m_a_k_e_f_i_l_e is `--', standard input is read.  Multiple makefiles may
136             be specified, and are read in the order specified.
137
138     --II _d_i_r_e_c_t_o_r_y
139             Specify a directory in which to search for makefiles and included
140             makefiles.  The system makefile directory (or directories, see
141             the --mm option) is automatically included as part of this list.
142
143     --ii      Ignore non-zero exit of shell commands in the makefile.  Equiva-
144             lent to specifying `--' before each command line in the makefile.
145
146     --JJ _p_r_i_v_a_t_e
147             This option should _n_o_t be specified by the user.
148
149             When the _j option is in use in a recursive build, this option is
150             passed by a make to child makes to allow all the make processes
151             in the build to cooperate to avoid overloading the system.
152
153     --jj _m_a_x___j_o_b_s
154             Specify the maximum number of jobs that bbmmaakkee may have running at
155             any one time.  The value is saved in _._M_A_K_E_._J_O_B_S.  Turns compati-
156             bility mode off, unless the _B flag is also specified.  When com-
157             patibility mode is off, all commands associated with a target are
158             executed in a single shell invocation as opposed to the tradi-
159             tional one shell invocation per line.  This can break traditional
160             scripts which change directories on each command invocation and
161             then expect to start with a fresh environment on the next line.
162             It is more efficient to correct the scripts rather than turn
163             backwards compatibility on.
164
165     --kk      Continue processing after errors are encountered, but only on
166             those targets that do not depend on the target whose creation
167             caused the error.
168
169     --mm _d_i_r_e_c_t_o_r_y
170             Specify a directory in which to search for sys.mk and makefiles
171             included via the <_f_i_l_e>-style include statement.  The --mm option
172             can be used multiple times to form a search path.  This path will
173             override the default system include path: /usr/share/mk.  Fur-
174             thermore the system include path will be appended to the search
175             path used for "_f_i_l_e"-style include statements (see the --II
176             option).
177
178             If a file or directory name in the --mm argument (or the
179             MAKESYSPATH environment variable) starts with the string ".../"
180             then bbmmaakkee will search for the specified file or directory named
181             in the remaining part of the argument string.  The search starts
182             with the current directory of the Makefile and then works upward
183             towards the root of the file system.  If the search is success-
184             ful, then the resulting directory replaces the ".../" specifica-
185             tion in the --mm argument.  If used, this feature allows bbmmaakkee to
186             easily search in the current source tree for customized sys.mk
187             files (e.g., by using ".../mk/sys.mk" as an argument).
188
189     --nn      Display the commands that would have been executed, but do not
190             actually execute them unless the target depends on the .MAKE spe-
191             cial source (see below).
192
193     --NN      Display the commands which would have been executed, but do not
194             actually execute any of them; useful for debugging top-level
195             makefiles without descending into subdirectories.
196
197     --qq      Do not execute any commands, but exit 0 if the specified targets
198             are up-to-date and 1, otherwise.
199
200     --rr      Do not use the built-in rules specified in the system makefile.
201
202     --ss      Do not echo any commands as they are executed.  Equivalent to
203             specifying `@@' before each command line in the makefile.
204
205     --TT _t_r_a_c_e_f_i_l_e
206             When used with the --jj flag, append a trace record to _t_r_a_c_e_f_i_l_e
207             for each job started and completed.
208
209     --tt      Rather than re-building a target as specified in the makefile,
210             create it or update its modification time to make it appear up-
211             to-date.
212
213     --VV _v_a_r_i_a_b_l_e
214             Print the value of _v_a_r_i_a_b_l_e.  Do not build any targets.  Multiple
215             instances of this option may be specified; the variables will be
216             printed one per line, with a blank line for each null or unde-
217             fined variable.  The value printed is extracted from the global
218             context after all makefiles have been read.  By default, the raw
219             variable contents (which may include additional unexpanded vari-
220             able references) are shown.  If _v_a_r_i_a_b_l_e contains a `$' then the
221             value will be recursively expanded to its complete resultant text
222             before printing.  The expanded value will also be printed if
223             _._M_A_K_E_._E_X_P_A_N_D___V_A_R_I_A_B_L_E_S is set to true and the --ddVV option has not
224             been used to override it.  Note that loop-local and target-local
225             variables, as well as values taken temporarily by global vari-
226             ables during makefile processing, are not accessible via this
227             option.  The --ddvv debug mode can be used to see these at the cost
228             of generating substantial extraneous output.
229
230     --vv _v_a_r_i_a_b_l_e
231             Like --VV but the variable is always expanded to its complete
232             value.
233
234     --WW      Treat any warnings during makefile parsing as errors.
235
236     --ww      Print entering and leaving directory messages, pre and post pro-
237             cessing.
238
239     --XX      Don't export variables passed on the command line to the environ-
240             ment individually.  Variables passed on the command line are
241             still exported via the _M_A_K_E_F_L_A_G_S environment variable.  This
242             option may be useful on systems which have a small limit on the
243             size of command arguments.
244
245     _v_a_r_i_a_b_l_e_=_v_a_l_u_e
246             Set the value of the variable _v_a_r_i_a_b_l_e to _v_a_l_u_e.  Normally, all
247             values passed on the command line are also exported to sub-makes
248             in the environment.  The --XX flag disables this behavior.  Vari-
249             able assignments should follow options for POSIX compatibility
250             but no ordering is enforced.
251
252     There are seven different types of lines in a makefile: file dependency
253     specifications, shell commands, variable assignments, include statements,
254     conditional directives, for loops, and comments.
255
256     In general, lines may be continued from one line to the next by ending
257     them with a backslash (`\').  The trailing newline character and initial
258     whitespace on the following line are compressed into a single space.
259
260FFIILLEE DDEEPPEENNDDEENNCCYY SSPPEECCIIFFIICCAATTIIOONNSS
261     Dependency lines consist of one or more targets, an operator, and zero or
262     more sources.  This creates a relationship where the targets ``depend''
263     on the sources and are usually created from them.  The exact relationship
264     between the target and the source is determined by the operator that sep-
265     arates them.  The three operators are as follows:
266
267     ::     A target is considered out-of-date if its modification time is less
268           than those of any of its sources.  Sources for a target accumulate
269           over dependency lines when this operator is used.  The target is
270           removed if bbmmaakkee is interrupted.
271
272     !!     Targets are always re-created, but not until all sources have been
273           examined and re-created as necessary.  Sources for a target accumu-
274           late over dependency lines when this operator is used.  The target
275           is removed if bbmmaakkee is interrupted.
276
277     ::::    If no sources are specified, the target is always re-created.  Oth-
278           erwise, a target is considered out-of-date if any of its sources
279           has been modified more recently than the target.  Sources for a
280           target do not accumulate over dependency lines when this operator
281           is used.  The target will not be removed if bbmmaakkee is interrupted.
282
283     Targets and sources may contain the shell wildcard values `?', `*', `[]',
284     and `{}'.  The values `?', `*', and `[]' may only be used as part of the
285     final component of the target or source, and must be used to describe
286     existing files.  The value `{}' need not necessarily be used to describe
287     existing files.  Expansion is in directory order, not alphabetically as
288     done in the shell.
289
290SSHHEELLLL CCOOMMMMAANNDDSS
291     Each target may have associated with it one or more lines of shell com-
292     mands, normally used to create the target.  Each of the lines in this
293     script _m_u_s_t be preceded by a tab.  (For historical reasons, spaces are
294     not accepted.)  While targets can appear in many dependency lines if
295     desired, by default only one of these rules may be followed by a creation
296     script.  If the `::::' operator is used, however, all rules may include
297     scripts and the scripts are executed in the order found.
298
299     Each line is treated as a separate shell command, unless the end of line
300     is escaped with a backslash (`\') in which case that line and the next
301     are combined.  If the first characters of the command are any combination
302     of `@@', `++', or `--', the command is treated specially.  A `@@' causes the
303     command not to be echoed before it is executed.  A `++' causes the command
304     to be executed even when --nn is given.  This is similar to the effect of
305     the .MAKE special source, except that the effect can be limited to a sin-
306     gle line of a script.  A `--' in compatibility mode causes any non-zero
307     exit status of the command line to be ignored.
308
309     When bbmmaakkee is run in jobs mode with --jj _m_a_x___j_o_b_s, the entire script for
310     the target is fed to a single instance of the shell.  In compatibility
311     (non-jobs) mode, each command is run in a separate process.  If the com-
312     mand contains any shell meta characters (`#=|^(){};&<>*?[]:$`\\n') it
313     will be passed to the shell; otherwise bbmmaakkee will attempt direct execu-
314     tion.  If a line starts with `--' and the shell has ErrCtl enabled then
315     failure of the command line will be ignored as in compatibility mode.
316     Otherwise `--' affects the entire job; the script will stop at the first
317     command line that fails, but the target will not be deemed to have
318     failed.
319
320     Makefiles should be written so that the mode of bbmmaakkee operation does not
321     change their behavior.  For example, any command which needs to use
322     ``cd'' or ``chdir'' without potentially changing the directory for subse-
323     quent commands should be put in parentheses so it executes in a subshell.
324     To force the use of one shell, escape the line breaks so as to make the
325     whole script one command.  For example:
326
327           avoid-chdir-side-effects:
328                   @echo Building $@ in `pwd`
329                   @(cd ${.CURDIR} && ${MAKE} $@)
330                   @echo Back in `pwd`
331
332           ensure-one-shell-regardless-of-mode:
333                   @echo Building $@ in `pwd`; \
334                   (cd ${.CURDIR} && ${MAKE} $@); \
335                   echo Back in `pwd`
336
337     Since bbmmaakkee will chdir(2) to `_._O_B_J_D_I_R' before executing any targets, each
338     child process starts with that as its current working directory.
339
340VVAARRIIAABBLLEE AASSSSIIGGNNMMEENNTTSS
341     Variables in make are much like variables in the shell, and, by tradi-
342     tion, consist of all upper-case letters.
343
344   VVaarriiaabbllee aassssiiggnnmmeenntt mmooddiiffiieerrss
345     The five operators that can be used to assign values to variables are as
346     follows:
347
348     ==       Assign the value to the variable.  Any previous value is overrid-
349             den.
350
351     ++==      Append the value to the current value of the variable.
352
353     ??==      Assign the value to the variable if it is not already defined.
354
355     ::==      Assign with expansion, i.e. expand the value before assigning it
356             to the variable.  Normally, expansion is not done until the vari-
357             able is referenced.  _N_O_T_E: References to undefined variables are
358             _n_o_t expanded.  This can cause problems when variable modifiers
359             are used.
360
361     !!==      Expand the value and pass it to the shell for execution and
362             assign the result to the variable.  Any newlines in the result
363             are replaced with spaces.
364
365     Any white-space before the assigned _v_a_l_u_e is removed; if the value is
366     being appended, a single space is inserted between the previous contents
367     of the variable and the appended value.
368
369     Variables are expanded by surrounding the variable name with either curly
370     braces (`{}') or parentheses (`()') and preceding it with a dollar sign
371     (`$').  If the variable name contains only a single letter, the surround-
372     ing braces or parentheses are not required.  This shorter form is not
373     recommended.
374
375     If the variable name contains a dollar, then the name itself is expanded
376     first.  This allows almost arbitrary variable names, however names con-
377     taining dollar, braces, parenthesis, or whitespace are really best
378     avoided!
379
380     If the result of expanding a variable contains a dollar sign (`$') the
381     string is expanded again.
382
383     Variable substitution occurs at three distinct times, depending on where
384     the variable is being used.
385
386     1.   Variables in dependency lines are expanded as the line is read.
387
388     2.   Variables in shell commands are expanded when the shell command is
389          executed.
390
391     3.   ``.for'' loop index variables are expanded on each loop iteration.
392          Note that other variables are not expanded inside loops so the fol-
393          lowing example code:
394
395
396                .for i in 1 2 3
397                a+=     ${i}
398                j=      ${i}
399                b+=     ${j}
400                .endfor
401
402                all:
403                        @echo ${a}
404                        @echo ${b}
405
406          will print:
407
408                1 2 3
409                3 3 3
410
411          Because while ${a} contains ``1 2 3'' after the loop is executed,
412          ${b} contains ``${j} ${j} ${j}'' which expands to ``3 3 3'' since
413          after the loop completes ${j} contains ``3''.
414
415   VVaarriiaabbllee ccllaasssseess
416     The four different classes of variables (in order of increasing prece-
417     dence) are:
418
419     Environment variables
420             Variables defined as part of bbmmaakkee's environment.
421
422     Global variables
423             Variables defined in the makefile or in included makefiles.
424
425     Command line variables
426             Variables defined as part of the command line.
427
428     Local variables
429             Variables that are defined specific to a certain target.
430
431     Local variables are all built in and their values vary magically from
432     target to target.  It is not currently possible to define new local vari-
433     ables.  The seven local variables are as follows:
434
435           _._A_L_L_S_R_C   The list of all sources for this target; also known as
436                     `_>'.
437
438           _._A_R_C_H_I_V_E  The name of the archive file; also known as `_!'.
439
440           _._I_M_P_S_R_C   In suffix-transformation rules, the name/path of the
441                     source from which the target is to be transformed (the
442                     ``implied'' source); also known as `_<'.  It is not
443                     defined in explicit rules.
444
445           _._M_E_M_B_E_R   The name of the archive member; also known as `_%'.
446
447           _._O_O_D_A_T_E   The list of sources for this target that were deemed out-
448                     of-date; also known as `_?'.
449
450           _._P_R_E_F_I_X   The file prefix of the target, containing only the file
451                     portion, no suffix or preceding directory components;
452                     also known as `_*'.  The suffix must be one of the known
453                     suffixes declared with ..SSUUFFFFIIXXEESS or it will not be recog-
454                     nized.
455
456           _._T_A_R_G_E_T   The name of the target; also known as `_@'.  For compati-
457                     bility with other makes this is an alias for ..AARRCCHHIIVVEE in
458                     archive member rules.
459
460     The shorter forms (`_>', `_!', `_<', `_%', `_?', `_*', and `_@') are permitted
461     for backward compatibility with historical makefiles and legacy POSIX
462     make and are not recommended.
463
464     Variants of these variables with the punctuation followed immediately by
465     `D' or `F', e.g.  `_$_(_@_D_)', are legacy forms equivalent to using the `:H'
466     and `:T' modifiers.  These forms are accepted for compatibility with AT&T
467     System V UNIX makefiles and POSIX but are not recommended.
468
469     Four of the local variables may be used in sources on dependency lines
470     because they expand to the proper value for each target on the line.
471     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'.
472
473   AAddddiittiioonnaall bbuuiilltt--iinn vvaarriiaabblleess
474     In addition, bbmmaakkee sets or knows about the following variables:
475
476     _$               A single dollar sign `$', i.e.  `$$' expands to a single
477                     dollar sign.
478
479     _._A_L_L_T_A_R_G_E_T_S     The list of all targets encountered in the Makefile.  If
480                     evaluated during Makefile parsing, lists only those tar-
481                     gets encountered thus far.
482
483     _._C_U_R_D_I_R         A path to the directory where bbmmaakkee was executed.  Refer
484                     to the description of `PWD' for more details.
485
486     _._I_N_C_L_U_D_E_D_F_R_O_M_D_I_R
487                     The directory of the file this Makefile was included
488                     from.
489
490     _._I_N_C_L_U_D_E_D_F_R_O_M_F_I_L_E
491                     The filename of the file this Makefile was included from.
492
493     MAKE            The name that bbmmaakkee was executed with (_a_r_g_v_[_0_]).  For
494                     compatibility bbmmaakkee also sets _._M_A_K_E with the same value.
495                     The preferred variable to use is the environment variable
496                     MAKE because it is more compatible with other versions of
497                     bbmmaakkee and cannot be confused with the special target with
498                     the same name.
499
500     _._M_A_K_E_._D_E_P_E_N_D_F_I_L_E
501                     Names the makefile (default `_._d_e_p_e_n_d') from which gener-
502                     ated dependencies are read.
503
504     _._M_A_K_E_._E_X_P_A_N_D___V_A_R_I_A_B_L_E_S
505                     A boolean that controls the default behavior of the --VV
506                     option.  If true, variable values printed with --VV are
507                     fully expanded; if false, the raw variable contents
508                     (which may include additional unexpanded variable refer-
509                     ences) are shown.
510
511     _._M_A_K_E_._E_X_P_O_R_T_E_D  The list of variables exported by bbmmaakkee.
512
513     _._M_A_K_E_._J_O_B_S      The argument to the --jj option.
514
515     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X
516                     If bbmmaakkee is run with _j then output for each target is
517                     prefixed with a token `--- target ---' the first part of
518                     which can be controlled via _._M_A_K_E_._J_O_B_._P_R_E_F_I_X.  If
519                     _._M_A_K_E_._J_O_B_._P_R_E_F_I_X is empty, no token is printed.
520                     For example:
521                     .MAKE.JOB.PREFIX=${.newline}---${.MAKE:T}[${.MAKE.PID}]
522                     would produce tokens like `---make[1234] target ---' mak-
523                     ing it easier to track the degree of parallelism being
524                     achieved.
525
526     MAKEFLAGS       The environment variable `MAKEFLAGS' may contain anything
527                     that may be specified on bbmmaakkee's command line.  Anything
528                     specified on bbmmaakkee's command line is appended to the
529                     `MAKEFLAGS' variable which is then entered into the envi-
530                     ronment for all programs which bbmmaakkee executes.
531
532     _._M_A_K_E_._L_E_V_E_L     The recursion depth of bbmmaakkee.  The initial instance of
533                     bbmmaakkee will be 0, and an incremented value is put into the
534                     environment to be seen by the next generation.  This
535                     allows tests like: .if ${.MAKE.LEVEL} == 0 to protect
536                     things which should only be evaluated in the initial
537                     instance of bbmmaakkee.
538
539     _._M_A_K_E_._M_A_K_E_F_I_L_E___P_R_E_F_E_R_E_N_C_E
540                     The ordered list of makefile names (default `_m_a_k_e_f_i_l_e',
541                     `_M_a_k_e_f_i_l_e') that bbmmaakkee will look for.
542
543     _._M_A_K_E_._M_A_K_E_F_I_L_E_S
544                     The list of makefiles read by bbmmaakkee, which is useful for
545                     tracking dependencies.  Each makefile is recorded only
546                     once, regardless of the number of times read.
547
548     _._M_A_K_E_._M_O_D_E      Processed after reading all makefiles.  Can affect the
549                     mode that bbmmaakkee runs in.  It can contain a number of key-
550                     words:
551
552                     _c_o_m_p_a_t               Like --BB, puts bbmmaakkee into "compat"
553                                          mode.
554
555                     _m_e_t_a                 Puts bbmmaakkee into "meta" mode, where
556                                          meta files are created for each tar-
557                                          get to capture the command run, the
558                                          output generated and if filemon(4)
559                                          is available, the system calls which
560                                          are of interest to bbmmaakkee.  The cap-
561                                          tured output can be very useful when
562                                          diagnosing errors.
563
564                     _c_u_r_d_i_r_O_k_= _b_f         Normally bbmmaakkee will not create .meta
565                                          files in `_._C_U_R_D_I_R'.  This can be
566                                          overridden by setting _b_f to a value
567                                          which represents True.
568
569                     _m_i_s_s_i_n_g_-_m_e_t_a_= _b_f     If _b_f is True, then a missing .meta
570                                          file makes the target out-of-date.
571
572                     _m_i_s_s_i_n_g_-_f_i_l_e_m_o_n_= _b_f  If _b_f is True, then missing filemon
573                                          data makes the target out-of-date.
574
575                     _n_o_f_i_l_e_m_o_n            Do not use filemon(4).
576
577                     _e_n_v                  For debugging, it can be useful to
578                                          include the environment in the .meta
579                                          file.
580
581                     _v_e_r_b_o_s_e              If in "meta" mode, print a clue
582                                          about the target being built.  This
583                                          is useful if the build is otherwise
584                                          running silently.  The message
585                                          printed the value of:
586                                          _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X.
587
588                     _i_g_n_o_r_e_-_c_m_d           Some makefiles have commands which
589                                          are simply not stable.  This keyword
590                                          causes them to be ignored for deter-
591                                          mining whether a target is out of
592                                          date in "meta" mode.  See also
593                                          ..NNOOMMEETTAA__CCMMPP.
594
595                     _s_i_l_e_n_t_= _b_f           If _b_f is True, when a .meta file is
596                                          created, mark the target ..SSIILLEENNTT.
597
598     _._M_A_K_E_._M_E_T_A_._B_A_I_L_I_W_I_C_K
599                     In "meta" mode, provides a list of prefixes which match
600                     the directories controlled by bbmmaakkee.  If a file that was
601                     generated outside of _._O_B_J_D_I_R but within said bailiwick is
602                     missing, the current target is considered out-of-date.
603
604     _._M_A_K_E_._M_E_T_A_._C_R_E_A_T_E_D
605                     In "meta" mode, this variable contains a list of all the
606                     meta files updated.  If not empty, it can be used to
607                     trigger processing of _._M_A_K_E_._M_E_T_A_._F_I_L_E_S.
608
609     _._M_A_K_E_._M_E_T_A_._F_I_L_E_S
610                     In "meta" mode, this variable contains a list of all the
611                     meta files used (updated or not).  This list can be used
612                     to process the meta files to extract dependency informa-
613                     tion.
614
615     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___P_A_T_H_S
616                     Provides a list of path prefixes that should be ignored;
617                     because the contents are expected to change over time.
618                     The default list includes: `_/_d_e_v _/_e_t_c _/_p_r_o_c _/_t_m_p _/_v_a_r_/_r_u_n
619                     _/_v_a_r_/_t_m_p'
620
621     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___P_A_T_T_E_R_N_S
622                     Provides a list of patterns to match against pathnames.
623                     Ignore any that match.
624
625     _._M_A_K_E_._M_E_T_A_._I_G_N_O_R_E___F_I_L_T_E_R
626                     Provides a list of variable modifiers to apply to each
627                     pathname.  Ignore if the expansion is an empty string.
628
629     _._M_A_K_E_._M_E_T_A_._P_R_E_F_I_X
630                     Defines the message printed for each meta file updated in
631                     "meta verbose" mode.  The default value is:
632                           Building ${.TARGET:H:tA}/${.TARGET:T}
633
634     _._M_A_K_E_O_V_E_R_R_I_D_E_S  This variable is used to record the names of variables
635                     assigned to on the command line, so that they may be
636                     exported as part of `MAKEFLAGS'.  This behavior can be
637                     disabled by assigning an empty value to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'
638                     within a makefile.  Extra variables can be exported from
639                     a makefile by appending their names to `_._M_A_K_E_O_V_E_R_R_I_D_E_S'.
640                     `MAKEFLAGS' is re-exported whenever `_._M_A_K_E_O_V_E_R_R_I_D_E_S' is
641                     modified.
642
643     _._M_A_K_E_._P_A_T_H___F_I_L_E_M_O_N
644                     If bbmmaakkee was built with filemon(4) support, this is set
645                     to the path of the device node.  This allows makefiles to
646                     test for this support.
647
648     _._M_A_K_E_._P_I_D       The process-id of bbmmaakkee.
649
650     _._M_A_K_E_._P_P_I_D      The parent process-id of bbmmaakkee.
651
652     _._M_A_K_E_._S_A_V_E___D_O_L_L_A_R_S
653                     value should be a boolean that controls whether `$$' are
654                     preserved when doing `:=' assignments.  The default is
655                     false, for backwards compatibility.  Set to true for com-
656                     patability with other makes.  If set to false, `$$'
657                     becomes `$' per normal evaluation rules.
658
659     _M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R
660                     When bbmmaakkee stops due to an error, it sets `_._E_R_R_O_R___T_A_R_G_E_T'
661                     to the name of the target that failed, `_._E_R_R_O_R___C_M_D' to
662                     the commands of the failed target, and in "meta" mode, it
663                     also sets `_._E_R_R_O_R___C_W_D' to the getcwd(3), and
664                     `_._E_R_R_O_R___M_E_T_A___F_I_L_E' to the path of the meta file (if any)
665                     describing the failed target.  It then prints its name
666                     and the value of `_._C_U_R_D_I_R' as well as the value of any
667                     variables named in `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R'.
668
669     _._n_e_w_l_i_n_e        This variable is simply assigned a newline character as
670                     its value.  This allows expansions using the ::@@ modifier
671                     to put a newline between iterations of the loop rather
672                     than a space.  For example, the printing of
673                     `_M_A_K_E___P_R_I_N_T___V_A_R___O_N___E_R_R_O_R' could be done as
674                     ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}.
675
676     _._O_B_J_D_I_R         A path to the directory where the targets are built.  Its
677                     value is determined by trying to chdir(2) to the follow-
678                     ing directories in order and using the first match:
679
680                     1.   ${MAKEOBJDIRPREFIX}${.CURDIR}
681
682                          (Only if `MAKEOBJDIRPREFIX' is set in the environ-
683                          ment or on the command line.)
684
685                     2.   ${MAKEOBJDIR}
686
687                          (Only if `MAKEOBJDIR' is set in the environment or
688                          on the command line.)
689
690                     3.   ${.CURDIR}_/_o_b_j_.${MACHINE}
691
692                     4.   ${.CURDIR}_/_o_b_j
693
694                     5.   _/_u_s_r_/_o_b_j_/${.CURDIR}
695
696                     6.   ${.CURDIR}
697
698                     Variable expansion is performed on the value before it's
699                     used, so expressions such as
700                           ${.CURDIR:S,^/usr/src,/var/obj,}
701                     may be used.  This is especially useful with
702                     `MAKEOBJDIR'.
703
704                     `_._O_B_J_D_I_R' may be modified in the makefile via the special
705                     target `..OOBBJJDDIIRR'.  In all cases, bbmmaakkee will chdir(2) to
706                     the specified directory if it exists, and set `_._O_B_J_D_I_R'
707                     and `PWD' to that directory before executing any targets.
708
709     _._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
710                     parsed.
711
712     _._P_A_R_S_E_F_I_L_E      The basename of the current `_M_a_k_e_f_i_l_e' being parsed.
713                     This variable and `_._P_A_R_S_E_D_I_R' are both set only while the
714                     `_M_a_k_e_f_i_l_e_s' are being parsed.  If you want to retain
715                     their current values, assign them to a variable using
716                     assignment with expansion: (`::==').
717
718     _._P_A_T_H           A variable that represents the list of directories that
719                     bbmmaakkee will search for files.  The search list should be
720                     updated using the target `_._P_A_T_H' rather than the vari-
721                     able.
722
723     PWD             Alternate path to the current directory.  bbmmaakkee normally
724                     sets `_._C_U_R_D_I_R' to the canonical path given by getcwd(3).
725                     However, if the environment variable `PWD' is set and
726                     gives a path to the current directory, then bbmmaakkee sets
727                     `_._C_U_R_D_I_R' to the value of `PWD' instead.  This behavior
728                     is disabled if `MAKEOBJDIRPREFIX' is set or `MAKEOBJDIR'
729                     contains a variable transform.  `PWD' is set to the value
730                     of `_._O_B_J_D_I_R' for all programs which bbmmaakkee executes.
731
732     .TARGETS        The list of targets explicitly specified on the command
733                     line, if any.
734
735     VPATH           Colon-separated (``:'') lists of directories that bbmmaakkee
736                     will search for files.  The variable is supported for
737                     compatibility with old make programs only, use `_._P_A_T_H'
738                     instead.
739
740   VVaarriiaabbllee mmooddiiffiieerrss
741     Variable expansion may be modified to select or modify each word of the
742     variable (where a ``word'' is white-space delimited sequence of charac-
743     ters).  The general format of a variable expansion is as follows:
744
745           ${variable[:modifier[:...]]}
746
747     Each modifier begins with a colon, which may be escaped with a backslash
748     (`\').
749
750     A set of modifiers can be specified via a variable, as follows:
751
752           modifier_variable=modifier[:...]
753           ${variable:${modifier_variable}[:...]}
754
755     In this case the first modifier in the modifier_variable does not start
756     with a colon, since that must appear in the referencing variable.  If any
757     of the modifiers in the modifier_variable contain a dollar sign (`$'),
758     these must be doubled to avoid early expansion.
759
760     The supported modifiers are:
761
762     ::EE   Replaces each word in the variable with its suffix.
763
764     ::HH   Replaces each word in the variable with everything but the last com-
765          ponent.
766
767     ::MM_p_a_t_t_e_r_n
768          Select only those words that match _p_a_t_t_e_r_n.  The standard shell
769          wildcard characters (`*', `?', and `[]') may be used.  The wildcard
770          characters may be escaped with a backslash (`\').  As a consequence
771          of the way values are split into words, matched, and then joined, a
772          construct like
773                ${VAR:M*}
774          will normalize the inter-word spacing, removing all leading and
775          trailing space, and converting multiple consecutive spaces to single
776          spaces.
777
778     ::NN_p_a_t_t_e_r_n
779          This is identical to `::MM', but selects all words which do not match
780          _p_a_t_t_e_r_n.
781
782     ::OO   Order every word in variable alphabetically.  To sort words in
783          reverse order use the `::OO::[[--11....11]]' combination of modifiers.
784
785     ::OOxx  Randomize words in variable.  The results will be different each
786          time you are referring to the modified variable; use the assignment
787          with expansion (`::==') to prevent such behavior.  For example,
788
789                LIST=                   uno due tre quattro
790                RANDOM_LIST=            ${LIST:Ox}
791                STATIC_RANDOM_LIST:=    ${LIST:Ox}
792
793                all:
794                        @echo "${RANDOM_LIST}"
795                        @echo "${RANDOM_LIST}"
796                        @echo "${STATIC_RANDOM_LIST}"
797                        @echo "${STATIC_RANDOM_LIST}"
798          may produce output similar to:
799
800                quattro due tre uno
801                tre due quattro uno
802                due uno quattro tre
803                due uno quattro tre
804
805     ::QQ   Quotes every shell meta-character in the variable, so that it can be
806          passed safely through recursive invocations of bbmmaakkee.
807
808     ::RR   Replaces each word in the variable with everything but its suffix.
809
810     ::rraannggee[[==ccoouunntt]]
811          The value is an integer sequence representing the words of the orig-
812          inal value, or the supplied _c_o_u_n_t.
813
814     ::ggmmttiimmee[[==uuttcc]]
815          The value is a format string for strftime(3), using gmtime(3).  If a
816          _u_t_c value is not provided or is 0, the current time is used.
817
818     ::hhaasshh
819          Compute a 32-bit hash of the value and encode it as hex digits.
820
821     ::llooccaallttiimmee[[==uuttcc]]
822          The value is a format string for strftime(3), using localtime(3).
823          If a _u_t_c value is not provided or is 0, the current time is used.
824
825     ::ttAA  Attempt to convert variable to an absolute path using realpath(3),
826          if that fails, the value is unchanged.
827
828     ::ttll  Converts variable to lower-case letters.
829
830     ::ttss_c
831          Words in the variable are normally separated by a space on expan-
832          sion.  This modifier sets the separator to the character _c.  If _c is
833          omitted, then no separator is used.  The common escapes (including
834          octal numeric codes), work as expected.
835
836     ::ttuu  Converts variable to upper-case letters.
837
838     ::ttWW  Causes the value to be treated as a single word (possibly containing
839          embedded white space).  See also `::[[**]]'.
840
841     ::ttww  Causes the value to be treated as a sequence of words delimited by
842          white space.  See also `::[[@@]]'.
843
844     ::SS/_o_l_d___s_t_r_i_n_g/_n_e_w___s_t_r_i_n_g/[11ggWW]
845          Modify the first occurrence of _o_l_d___s_t_r_i_n_g in the variable's value,
846          replacing it with _n_e_w___s_t_r_i_n_g.  If a `g' is appended to the last
847          slash of the pattern, all occurrences in each word are replaced.  If
848          a `1' is appended to the last slash of the pattern, only the first
849          word is affected.  If a `W' is appended to the last slash of the
850          pattern, then the value is treated as a single word (possibly con-
851          taining embedded white space).  If _o_l_d___s_t_r_i_n_g begins with a caret
852          (`^'), _o_l_d___s_t_r_i_n_g is anchored at the beginning of each word.  If
853          _o_l_d___s_t_r_i_n_g ends with a dollar sign (`$'), it is anchored at the end
854          of each word.  Inside _n_e_w___s_t_r_i_n_g, an ampersand (`&') is replaced by
855          _o_l_d___s_t_r_i_n_g (without any `^' or `$').  Any character may be used as a
856          delimiter for the parts of the modifier string.  The anchoring,
857          ampersand and delimiter characters may be escaped with a backslash
858          (`\').
859
860          Variable expansion occurs in the normal fashion inside both
861          _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
862          is used to prevent the expansion of a dollar sign (`$'), not a pre-
863          ceding dollar sign as is usual.
864
865     ::CC/_p_a_t_t_e_r_n/_r_e_p_l_a_c_e_m_e_n_t/[11ggWW]
866          The ::CC modifier is just like the ::SS modifier except that the old and
867          new strings, instead of being simple strings, are an extended regu-
868          lar expression (see regex(3)) string _p_a_t_t_e_r_n and an ed(1)-style
869          string _r_e_p_l_a_c_e_m_e_n_t.  Normally, the first occurrence of the pattern
870          _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.
871          The `1' modifier causes the substitution to apply to at most one
872          word; the `g' modifier causes the substitution to apply to as many
873          instances of the search pattern _p_a_t_t_e_r_n as occur in the word or
874          words it is found in; the `W' modifier causes the value to be
875          treated as a single word (possibly containing embedded white space).
876          Note that `1' and `g' are orthogonal; the former specifies whether
877          multiple words are potentially affected, the latter whether multiple
878          substitutions can potentially occur within each affected word.
879
880          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
881          variable expansion before being parsed as regular expressions.
882
883     ::TT   Replaces each word in the variable with its last component.
884
885     ::uu   Remove adjacent duplicate words (like uniq(1)).
886
887     ::??_t_r_u_e___s_t_r_i_n_g::_f_a_l_s_e___s_t_r_i_n_g
888          If the variable name (not its value), when parsed as a .if condi-
889          tional expression, evaluates to true, return as its value the
890          _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
891          name is used as the expression, :? must be the first modifier after
892          the variable name itself - which will, of course, usually contain
893          variable expansions.  A common error is trying to use expressions
894          like
895                ${NUMBERS:M42:?match:no}
896          which actually tests defined(NUMBERS), to determine is any words
897          match "42" you need to use something like:
898                ${"${NUMBERS:M42}" != "":?match:no}.
899
900     _:_o_l_d___s_t_r_i_n_g_=_n_e_w___s_t_r_i_n_g
901          This is the AT&T System V UNIX style variable substitution.  It must
902          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
903          contain the pattern matching character _% then it is assumed that
904          they are anchored at the end of each word, so only suffixes or
905          entire words may be replaced.  Otherwise _% is the substring of
906          _o_l_d___s_t_r_i_n_g to be replaced in _n_e_w___s_t_r_i_n_g.
907
908          Variable expansion occurs in the normal fashion inside both
909          _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
910          is used to prevent the expansion of a dollar sign (`$'), not a pre-
911          ceding dollar sign as is usual.
912
913     ::@@_t_e_m_p@@_s_t_r_i_n_g@@
914          This is the loop expansion mechanism from the OSF Development Envi-
915          ronment (ODE) make.  Unlike ..ffoorr loops expansion occurs at the time
916          of reference.  Assign _t_e_m_p to each word in the variable and evaluate
917          _s_t_r_i_n_g.  The ODE convention is that _t_e_m_p should start and end with a
918          period.  For example.
919                ${LINKS:@.LINK.@${LN} ${TARGET} ${.LINK.}@}
920
921          However a single character variable is often more readable:
922                ${MAKE_PRINT_VAR_ON_ERROR:@v@$v='${$v}'${.newline}@}
923
924     ::__[[==vvaarr]]
925          Save the current variable value in `$_' or the named _v_a_r for later
926          reference.  Example usage:
927
928                M_cmpv.units = 1 1000 1000000
929                M_cmpv = S,., ,g:_:range:@i@+ $${_:[-$$i]} \
930                \* $${M_cmpv.units:[$$i]}@:S,^,expr 0 ,1:sh
931
932                .if ${VERSION:${M_cmpv}} < ${3.1.12:L:${M_cmpv}}
933
934          Here `$_' is used to save the result of the `:S' modifier which is
935          later referenced using the index values from `:range'.
936
937     ::UU_n_e_w_v_a_l
938          If the variable is undefined _n_e_w_v_a_l is the value.  If the variable
939          is defined, the existing value is returned.  This is another ODE
940          make feature.  It is handy for setting per-target CFLAGS for
941          instance:
942                ${_${.TARGET:T}_CFLAGS:U${DEF_CFLAGS}}
943          If a value is only required if the variable is undefined, use:
944                ${VAR:D:Unewval}
945
946     ::DD_n_e_w_v_a_l
947          If the variable is defined _n_e_w_v_a_l is the value.
948
949     ::LL   The name of the variable is the value.
950
951     ::PP   The path of the node which has the same name as the variable is the
952          value.  If no such node exists or its path is null, then the name of
953          the variable is used.  In order for this modifier to work, the name
954          (node) must at least have appeared on the rhs of a dependency.
955
956     ::!!_c_m_d!!
957          The output of running _c_m_d is the value.
958
959     ::sshh  If the variable is non-empty it is run as a command and the output
960          becomes the new value.
961
962     ::::==_s_t_r
963          The variable is assigned the value _s_t_r after substitution.  This
964          modifier and its variations are useful in obscure situations such as
965          wanting to set a variable when shell commands are being parsed.
966          These assignment modifiers always expand to nothing, so if appearing
967          in a rule line by themselves should be preceded with something to
968          keep bbmmaakkee happy.
969
970          The `::::' helps avoid false matches with the AT&T System V UNIX style
971          ::== modifier and since substitution always occurs the ::::== form is
972          vaguely appropriate.
973
974     ::::??==_s_t_r
975          As for ::::== but only if the variable does not already have a value.
976
977     ::::++==_s_t_r
978          Append _s_t_r to the variable.
979
980     ::::!!==_c_m_d
981          Assign the output of _c_m_d to the variable.
982
983     ::[[_r_a_n_g_e]]
984          Selects one or more words from the value, or performs other opera-
985          tions related to the way in which the value is divided into words.
986
987          Ordinarily, a value is treated as a sequence of words delimited by
988          white space.  Some modifiers suppress this behavior, causing a value
989          to be treated as a single word (possibly containing embedded white
990          space).  An empty value, or a value that consists entirely of white-
991          space, is treated as a single word.  For the purposes of the `::[[]]'
992          modifier, the words are indexed both forwards using positive inte-
993          gers (where index 1 represents the first word), and backwards using
994          negative integers (where index -1 represents the last word).
995
996          The _r_a_n_g_e is subjected to variable expansion, and the expanded
997          result is then interpreted as follows:
998
999          _i_n_d_e_x  Selects a single word from the value.
1000
1001          _s_t_a_r_t...._e_n_d
1002                 Selects all words from _s_t_a_r_t to _e_n_d, inclusive.  For example,
1003                 `::[[22....--11]]' selects all words from the second word to the last
1004                 word.  If _s_t_a_r_t is greater than _e_n_d, then the words are out-
1005                 put in reverse order.  For example, `::[[--11....11]]' selects all
1006                 the words from last to first.
1007
1008          **      Causes subsequent modifiers to treat the value as a single
1009                 word (possibly containing embedded white space).  Analogous
1010                 to the effect of "$*" in Bourne shell.
1011
1012          0      Means the same as `::[[**]]'.
1013
1014          @@      Causes subsequent modifiers to treat the value as a sequence
1015                 of words delimited by white space.  Analogous to the effect
1016                 of "$@" in Bourne shell.
1017
1018          ##      Returns the number of words in the value.
1019
1020IINNCCLLUUDDEE SSTTAATTEEMMEENNTTSS,, CCOONNDDIITTIIOONNAALLSS AANNDD FFOORR LLOOOOPPSS
1021     Makefile inclusion, conditional structures and for loops  reminiscent of
1022     the C programming language are provided in bbmmaakkee.  All such structures
1023     are identified by a line beginning with a single dot (`.') character.
1024     Files are included with either ..iinncclluuddee <_f_i_l_e> or ..iinncclluuddee "_f_i_l_e".  Vari-
1025     ables between the angle brackets or double quotes are expanded to form
1026     the file name.  If angle brackets are used, the included makefile is
1027     expected to be in the system makefile directory.  If double quotes are
1028     used, the including makefile's directory and any directories specified
1029     using the --II option are searched before the system makefile directory.
1030     For compatibility with other versions of bbmmaakkee `include file ...' is also
1031     accepted.
1032
1033     If the include statement is written as ..--iinncclluuddee or as ..ssiinncclluuddee then
1034     errors locating and/or opening include files are ignored.
1035
1036     If the include statement is written as ..ddiinncclluuddee not only are errors
1037     locating and/or opening include files ignored, but stale dependencies
1038     within the included file will be ignored just like _._M_A_K_E_._D_E_P_E_N_D_F_I_L_E.
1039
1040     Conditional expressions are also preceded by a single dot as the first
1041     character of a line.  The possible conditionals are as follows:
1042
1043     ..eerrrroorr _m_e_s_s_a_g_e
1044             The message is printed along with the name of the makefile and
1045             line number, then bbmmaakkee will exit.
1046
1047     ..eexxppoorrtt _v_a_r_i_a_b_l_e _._._.
1048             Export the specified global variable.  If no variable list is
1049             provided, all globals are exported except for internal variables
1050             (those that start with `.').  This is not affected by the --XX
1051             flag, so should be used with caution.  For compatibility with
1052             other bbmmaakkee programs `export variable=value' is also accepted.
1053
1054             Appending a variable name to _._M_A_K_E_._E_X_P_O_R_T_E_D is equivalent to
1055             exporting a variable.
1056
1057     ..eexxppoorrtt--eennvv _v_a_r_i_a_b_l_e _._._.
1058             The same as `.export', except that the variable is not appended
1059             to _._M_A_K_E_._E_X_P_O_R_T_E_D.  This allows exporting a value to the environ-
1060             ment which is different from that used by bbmmaakkee internally.
1061
1062     ..eexxppoorrtt--lliitteerraall _v_a_r_i_a_b_l_e _._._.
1063             The same as `.export-env', except that variables in the value are
1064             not expanded.
1065
1066     ..iinnffoo _m_e_s_s_a_g_e
1067             The message is printed along with the name of the makefile and
1068             line number.
1069
1070     ..uunnddeeff _v_a_r_i_a_b_l_e
1071             Un-define the specified global variable.  Only global variables
1072             may be un-defined.
1073
1074     ..uunneexxppoorrtt _v_a_r_i_a_b_l_e _._._.
1075             The opposite of `.export'.  The specified global _v_a_r_i_a_b_l_e will be
1076             removed from _._M_A_K_E_._E_X_P_O_R_T_E_D.  If no variable list is provided,
1077             all globals are unexported, and _._M_A_K_E_._E_X_P_O_R_T_E_D deleted.
1078
1079     ..uunneexxppoorrtt--eennvv
1080             Unexport all globals previously exported and clear the environ-
1081             ment inherited from the parent.  This operation will cause a mem-
1082             ory leak of the original environment, so should be used spar-
1083             ingly.  Testing for _._M_A_K_E_._L_E_V_E_L being 0, would make sense.  Also
1084             note that any variables which originated in the parent environ-
1085             ment should be explicitly preserved if desired.  For example:
1086
1087                   .if ${.MAKE.LEVEL} == 0
1088                   PATH := ${PATH}
1089                   .unexport-env
1090                   .export PATH
1091                   .endif
1092
1093             Would result in an environment containing only `PATH', which is
1094             the minimal useful environment.  Actually `.MAKE.LEVEL' will also
1095             be pushed into the new environment.
1096
1097     ..wwaarrnniinngg _m_e_s_s_a_g_e
1098             The message prefixed by `_w_a_r_n_i_n_g_:' is printed along with the name
1099             of the makefile and line number.
1100
1101     ..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 _._._.]
1102             Test the value of an expression.
1103
1104     ..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 _._._.]
1105             Test the value of a variable.
1106
1107     ..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 _._._.]
1108             Test the value of a variable.
1109
1110     ..iiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1111             Test the target being built.
1112
1113     ..iiffnnmmaakkee [!] _t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1114             Test the target being built.
1115
1116     ..eellssee   Reverse the sense of the last conditional.
1117
1118     ..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 _._._.]
1119             A combination of `..eellssee' followed by `..iiff'.
1120
1121     ..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 _._._.]
1122             A combination of `..eellssee' followed by `..iiffddeeff'.
1123
1124     ..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 _._._.]
1125             A combination of `..eellssee' followed by `..iiffnnddeeff'.
1126
1127     ..eelliiffmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1128             A combination of `..eellssee' followed by `..iiffmmaakkee'.
1129
1130     ..eelliiffnnmmaakkee [!]_t_a_r_g_e_t [_o_p_e_r_a_t_o_r _t_a_r_g_e_t _._._.]
1131             A combination of `..eellssee' followed by `..iiffnnmmaakkee'.
1132
1133     ..eennddiiff  End the body of the conditional.
1134
1135     The _o_p_e_r_a_t_o_r may be any one of the following:
1136
1137     ||||     Logical OR.
1138
1139     &&&&     Logical AND; of higher precedence than ``||''.
1140
1141     As in C, bbmmaakkee will only evaluate a conditional as far as is necessary to
1142     determine its value.  Parentheses may be used to change the order of
1143     evaluation.  The boolean operator `!!' may be used to logically negate an
1144     entire conditional.  It is of higher precedence than `&&&&'.
1145
1146     The value of _e_x_p_r_e_s_s_i_o_n may be any of the following:
1147
1148     ddeeffiinneedd  Takes a variable name as an argument and evaluates to true if
1149              the variable has been defined.
1150
1151     mmaakkee     Takes a target name as an argument and evaluates to true if the
1152              target was specified as part of bbmmaakkee's command line or was
1153              declared the default target (either implicitly or explicitly,
1154              see _._M_A_I_N) before the line containing the conditional.
1155
1156     eemmppttyy    Takes a variable, with possible modifiers, and evaluates to true
1157              if the expansion of the variable would result in an empty
1158              string.
1159
1160     eexxiissttss   Takes a file name as an argument and evaluates to true if the
1161              file exists.  The file is searched for on the system search path
1162              (see _._P_A_T_H).
1163
1164     ttaarrggeett   Takes a target name as an argument and evaluates to true if the
1165              target has been defined.
1166
1167     ccoommmmaannddss
1168              Takes a target name as an argument and evaluates to true if the
1169              target has been defined and has commands associated with it.
1170
1171     _E_x_p_r_e_s_s_i_o_n may also be an arithmetic or string comparison.  Variable
1172     expansion is performed on both sides of the comparison, after which the
1173     integral values are compared.  A value is interpreted as hexadecimal if
1174     it is preceded by 0x, otherwise it is decimal; octal numbers are not sup-
1175     ported.  The standard C relational operators are all supported.  If after
1176     variable expansion, either the left or right hand side of a `====' or `!!=='
1177     operator is not an integral value, then string comparison is performed
1178     between the expanded variables.  If no relational operator is given, it
1179     is assumed that the expanded variable is being compared against 0 or an
1180     empty string in the case of a string comparison.
1181
1182     When bbmmaakkee is evaluating one of these conditional expressions, and it
1183     encounters a (white-space separated) word it doesn't recognize, either
1184     the ``make'' or ``defined'' expression is applied to it, depending on the
1185     form of the conditional.  If the form is `..iiffddeeff', `..iiffnnddeeff', or `..iiff'
1186     the ``defined'' expression is applied.  Similarly, if the form is
1187     `..iiffmmaakkee' or `..iiffnnmmaakkee, tthhee' ``make'' expression is applied.
1188
1189     If the conditional evaluates to true the parsing of the makefile contin-
1190     ues as before.  If it evaluates to false, the following lines are
1191     skipped.  In both cases this continues until a `..eellssee' or `..eennddiiff' is
1192     found.
1193
1194     For loops are typically used to apply a set of rules to a list of files.
1195     The syntax of a for loop is:
1196
1197     ..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
1198     <make-rules>
1199     ..eennddffoorr
1200
1201     After the for eexxpprreessssiioonn is evaluated, it is split into words.  On each
1202     iteration of the loop, one word is taken and assigned to each vvaarriiaabbllee,
1203     in order, and these vvaarriiaabblleess are substituted into the mmaakkee--rruulleess inside
1204     the body of the for loop.  The number of words must come out even; that
1205     is, if there are three iteration variables, the number of words provided
1206     must be a multiple of three.
1207
1208CCOOMMMMEENNTTSS
1209     Comments begin with a hash (`#') character, anywhere but in a shell com-
1210     mand line, and continue to the end of an unescaped new line.
1211
1212SSPPEECCIIAALL SSOOUURRCCEESS ((AATTTTRRIIBBUUTTEESS))
1213     ..EEXXEECC     Target is never out of date, but always execute commands any-
1214               way.
1215
1216     ..IIGGNNOORREE   Ignore any errors from the commands associated with this tar-
1217               get, exactly as if they all were preceded by a dash (`-').
1218
1219     ..MMAADDEE     Mark all sources of this target as being up-to-date.
1220
1221     ..MMAAKKEE     Execute the commands associated with this target even if the --nn
1222               or --tt options were specified.  Normally used to mark recursive
1223               bbmmaakkees.
1224
1225     ..MMEETTAA     Create a meta file for the target, even if it is flagged as
1226               ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL.  Usage in conjunction with ..MMAAKKEE is
1227               the most likely case.  In "meta" mode, the target is out-of-
1228               date if the meta file is missing.
1229
1230     ..NNOOMMEETTAA   Do not create a meta file for the target.  Meta files are also
1231               not created for ..PPHHOONNYY, ..MMAAKKEE, or ..SSPPEECCIIAALL targets.
1232
1233     ..NNOOMMEETTAA__CCMMPP
1234               Ignore differences in commands when deciding if target is out
1235               of date.  This is useful if the command contains a value which
1236               always changes.  If the number of commands change, though, the
1237               target will still be out of date.  The same effect applies to
1238               any command line that uses the variable _._O_O_D_A_T_E, which can be
1239               used for that purpose even when not otherwise needed or
1240               desired:
1241
1242
1243                     skip-compare-for-some:
1244                             @echo this will be compared
1245                             @echo this will not ${.OODATE:M.NOMETA_CMP}
1246                             @echo this will also be compared
1247
1248               The ::MM pattern suppresses any expansion of the unwanted vari-
1249               able.
1250
1251     ..NNOOPPAATTHH   Do not search for the target in the directories specified by
1252               ..PPAATTHH.
1253
1254     ..NNOOTTMMAAIINN  Normally bbmmaakkee selects the first target it encounters as the
1255               default target to be built if no target was specified.  This
1256               source prevents this target from being selected.
1257
1258     ..OOPPTTIIOONNAALL
1259               If a target is marked with this attribute and bbmmaakkee can't fig-
1260               ure out how to create it, it will ignore this fact and assume
1261               the file isn't needed or already exists.
1262
1263     ..PPHHOONNYY    The target does not correspond to an actual file; it is always
1264               considered to be out of date, and will not be created with the
1265               --tt option.  Suffix-transformation rules are not applied to
1266               ..PPHHOONNYY targets.
1267
1268     ..PPRREECCIIOOUUSS
1269               When bbmmaakkee is interrupted, it normally removes any partially
1270               made targets.  This source prevents the target from being
1271               removed.
1272
1273     ..RREECCUURRSSIIVVEE
1274               Synonym for ..MMAAKKEE.
1275
1276     ..SSIILLEENNTT   Do not echo any of the commands associated with this target,
1277               exactly as if they all were preceded by an at sign (`@').
1278
1279     ..UUSSEE      Turn the target into bbmmaakkee's version of a macro.  When the tar-
1280               get is used as a source for another target, the other target
1281               acquires the commands, sources, and attributes (except for
1282               ..UUSSEE) of the source.  If the target already has commands, the
1283               ..UUSSEE target's commands are appended to them.
1284
1285     ..UUSSEEBBEEFFOORREE
1286               Exactly like ..UUSSEE, but prepend the ..UUSSEEBBEEFFOORREE target commands
1287               to the target.
1288
1289     ..WWAAIITT     If ..WWAAIITT appears in a dependency line, the sources that precede
1290               it are made before the sources that succeed it in the line.
1291               Since the dependents of files are not made until the file
1292               itself could be made, this also stops the dependents being
1293               built unless they are needed for another branch of the depen-
1294               dency tree.  So given:
1295
1296               x: a .WAIT b
1297                       echo x
1298               a:
1299                       echo a
1300               b: b1
1301                       echo b
1302               b1:
1303                       echo b1
1304
1305               the output is always `a', `b1', `b', `x'.
1306               The ordering imposed by ..WWAAIITT is only relevant for parallel
1307               makes.
1308
1309SSPPEECCIIAALL TTAARRGGEETTSS
1310     Special targets may not be included with other targets, i.e. they must be
1311     the only target specified.
1312
1313     ..BBEEGGIINN   Any command lines attached to this target are executed before
1314              anything else is done.
1315
1316     ..DDEEFFAAUULLTT
1317              This is sort of a ..UUSSEE rule for any target (that was used only
1318              as a source) that bbmmaakkee can't figure out any other way to cre-
1319              ate.  Only the shell script is used.  The ..IIMMPPSSRRCC variable of a
1320              target that inherits ..DDEEFFAAUULLTT's commands is set to the target's
1321              own name.
1322
1323     ..DDEELLEETTEE__OONN__EERRRROORR
1324              If this target is present in the makefile, it globally causes
1325              make to delete targets whose commands fail.  (By default, only
1326              targets whose commands are interrupted during execution are
1327              deleted.  This is the historical behavior.)  This setting can be
1328              used to help prevent half-finished or malformed targets from
1329              being left around and corrupting future rebuilds.
1330
1331     ..EENNDD     Any command lines attached to this target are executed after
1332              everything else is done.
1333
1334     ..EERRRROORR   Any command lines attached to this target are executed when
1335              another target fails.  The ..EERRRROORR__TTAARRGGEETT variable is set to the
1336              target that failed.  See also MMAAKKEE__PPRRIINNTT__VVAARR__OONN__EERRRROORR.
1337
1338     ..IIGGNNOORREE  Mark each of the sources with the ..IIGGNNOORREE attribute.  If no
1339              sources are specified, this is the equivalent of specifying the
1340              --ii option.
1341
1342     ..IINNTTEERRRRUUPPTT
1343              If bbmmaakkee is interrupted, the commands for this target will be
1344              executed.
1345
1346     ..MMAAIINN    If no target is specified when bbmmaakkee is invoked, this target
1347              will be built.
1348
1349     ..MMAAKKEEFFLLAAGGSS
1350              This target provides a way to specify flags for bbmmaakkee when the
1351              makefile is used.  The flags are as if typed to the shell,
1352              though the --ff option will have no effect.
1353
1354     ..NNOOPPAATTHH  Apply the ..NNOOPPAATTHH attribute to any specified sources.
1355
1356     ..NNOOTTPPAARRAALLLLEELL
1357              Disable parallel mode.
1358
1359     ..NNOO__PPAARRAALLLLEELL
1360              Synonym for ..NNOOTTPPAARRAALLLLEELL, for compatibility with other pmake
1361              variants.
1362
1363     ..OOBBJJDDIIRR  The source is a new value for `_._O_B_J_D_I_R'.  If it exists, bbmmaakkee
1364              will chdir(2) to it and update the value of `_._O_B_J_D_I_R'.
1365
1366     ..OORRDDEERR   The named targets are made in sequence.  This ordering does not
1367              add targets to the list of targets to be made.  Since the depen-
1368              dents of a target do not get built until the target itself could
1369              be built, unless `a' is built by another part of the dependency
1370              graph, the following is a dependency loop:
1371
1372              .ORDER: b a
1373              b: a
1374
1375              The ordering imposed by ..OORRDDEERR is only relevant for parallel
1376              makes.
1377
1378     ..PPAATTHH    The sources are directories which are to be searched for files
1379              not found in the current directory.  If no sources are speci-
1380              fied, any previously specified directories are deleted.  If the
1381              source is the special ..DDOOTTLLAASSTT target, then the current working
1382              directory is searched last.
1383
1384     ..PPAATTHH.._s_u_f_f_i_x
1385              Like ..PPAATTHH but applies only to files with a particular suffix.
1386              The suffix must have been previously declared with ..SSUUFFFFIIXXEESS.
1387
1388     ..PPHHOONNYY   Apply the ..PPHHOONNYY attribute to any specified sources.
1389
1390     ..PPRREECCIIOOUUSS
1391              Apply the ..PPRREECCIIOOUUSS attribute to any specified sources.  If no
1392              sources are specified, the ..PPRREECCIIOOUUSS attribute is applied to
1393              every target in the file.
1394
1395     ..SSHHEELLLL   Sets the shell that bbmmaakkee will use to execute commands.  The
1396              sources are a set of _f_i_e_l_d_=_v_a_l_u_e pairs.
1397
1398              _n_a_m_e        This is the minimal specification, used to select
1399                          one of the built-in shell specs; _s_h, _k_s_h, and _c_s_h.
1400
1401              _p_a_t_h        Specifies the path to the shell.
1402
1403              _h_a_s_E_r_r_C_t_l   Indicates whether the shell supports exit on error.
1404
1405              _c_h_e_c_k       The command to turn on error checking.
1406
1407              _i_g_n_o_r_e      The command to disable error checking.
1408
1409              _e_c_h_o        The command to turn on echoing of commands executed.
1410
1411              _q_u_i_e_t       The command to turn off echoing of commands exe-
1412                          cuted.
1413
1414              _f_i_l_t_e_r      The output to filter after issuing the _q_u_i_e_t com-
1415                          mand.  It is typically identical to _q_u_i_e_t.
1416
1417              _e_r_r_F_l_a_g     The flag to pass the shell to enable error checking.
1418
1419              _e_c_h_o_F_l_a_g    The flag to pass the shell to enable command echo-
1420                          ing.
1421
1422              _n_e_w_l_i_n_e     The string literal to pass the shell that results in
1423                          a single newline character when used outside of any
1424                          quoting characters.
1425              Example:
1426
1427              .SHELL: name=ksh path=/bin/ksh hasErrCtl=true \
1428                      check="set -e" ignore="set +e" \
1429                      echo="set -v" quiet="set +v" filter="set +v" \
1430                      echoFlag=v errFlag=e newline="'\n'"
1431
1432     ..SSIILLEENNTT  Apply the ..SSIILLEENNTT attribute to any specified sources.  If no
1433              sources are specified, the ..SSIILLEENNTT attribute is applied to every
1434              command in the file.
1435
1436     ..SSTTAALLEE   This target gets run when a dependency file contains stale
1437              entries, having _._A_L_L_S_R_C set to the name of that dependency file.
1438
1439     ..SSUUFFFFIIXXEESS
1440              Each source specifies a suffix to bbmmaakkee.  If no sources are
1441              specified, any previously specified suffixes are deleted.  It
1442              allows the creation of suffix-transformation rules.
1443
1444              Example:
1445
1446              .SUFFIXES: .o
1447              .c.o:
1448                      cc -o ${.TARGET} -c ${.IMPSRC}
1449
1450EENNVVIIRROONNMMEENNTT
1451     bbmmaakkee uses the following environment variables, if they exist: MACHINE,
1452     MACHINE_ARCH, MAKE, MAKEFLAGS, MAKEOBJDIR, MAKEOBJDIRPREFIX, MAKESYSPATH,
1453     PWD, and TMPDIR.
1454
1455     MAKEOBJDIRPREFIX and MAKEOBJDIR may only be set in the environment or on
1456     the command line to bbmmaakkee and not as makefile variables; see the descrip-
1457     tion of `_._O_B_J_D_I_R' for more details.
1458
1459FFIILLEESS
1460     .depend        list of dependencies
1461     Makefile       list of dependencies
1462     makefile       list of dependencies
1463     sys.mk         system makefile
1464     /usr/share/mk  system makefile directory
1465
1466CCOOMMPPAATTIIBBIILLIITTYY
1467     The basic make syntax is compatible between different versions of make;
1468     however the special variables, variable modifiers and conditionals are
1469     not.
1470
1471   OOllddeerr vveerrssiioonnss
1472     An incomplete list of changes in older versions of bbmmaakkee:
1473
1474     The way that .for loop variables are substituted changed after NetBSD 5.0
1475     so that they still appear to be variable expansions.  In particular this
1476     stops them being treated as syntax, and removes some obscure problems
1477     using them in .if statements.
1478
1479     The way that parallel makes are scheduled changed in NetBSD 4.0 so that
1480     .ORDER and .WAIT apply recursively to the dependent nodes.  The algo-
1481     rithms used may change again in the future.
1482
1483   OOtthheerr mmaakkee ddiiaalleeccttss
1484     Other make dialects (GNU make, SVR4 make, POSIX make, etc.) do not sup-
1485     port most of the features of bbmmaakkee as described in this manual.  Most
1486     notably:
1487
1488           ++oo   The ..WWAAIITT and ..OORRDDEERR declarations and most functionality per-
1489               taining to parallelization.  (GNU make supports parallelization
1490               but lacks these features needed to control it effectively.)
1491
1492           ++oo   Directives, including for loops and conditionals and most of
1493               the forms of include files.  (GNU make has its own incompatible
1494               and less powerful syntax for conditionals.)
1495
1496           ++oo   All built-in variables that begin with a dot.
1497
1498           ++oo   Most of the special sources and targets that begin with a dot,
1499               with the notable exception of ..PPHHOONNYY, ..PPRREECCIIOOUUSS, and ..SSUUFFFFIIXXEESS.
1500
1501           ++oo   Variable modifiers, except for the
1502                     :old=new
1503               string substitution, which does not portably support globbing
1504               with `%' and historically only works on declared suffixes.
1505
1506           ++oo   The $$>> variable even in its short form; most makes support this
1507               functionality but its name varies.
1508
1509     Some features are somewhat more portable, such as assignment with ++==, ??==,
1510     and !!==.  The ..PPAATTHH functionality is based on an older feature VVPPAATTHH found
1511     in GNU make and many versions of SVR4 make; however, historically its
1512     behavior is too ill-defined (and too buggy) to rely upon.
1513
1514     The $$@@ and $$<< variables are more or less universally portable, as is the
1515     $$((MMAAKKEE)) variable.  Basic use of suffix rules (for files only in the cur-
1516     rent directory, not trying to chain transformations together, etc.) is
1517     also reasonably portable.
1518
1519SSEEEE AALLSSOO
1520     mkdep(1)
1521
1522HHIISSTTOORRYY
1523     bbmmaakkee is derived from NetBSD make(1).  It uses autoconf to facilitate
1524     portability to other platforms.
1525
1526     A make command appeared in Version 7 AT&T UNIX.  This make implementation
1527     is based on Adam De Boor's pmake program which was written for Sprite at
1528     Berkeley.  It was designed to be a parallel distributed make running jobs
1529     on different machines using a daemon called ``customs''.
1530
1531     Historically the target/dependency ``FRC'' has been used to FoRCe
1532     rebuilding (since the target/dependency does not exist... unless someone
1533     creates an ``FRC'' file).
1534
1535BBUUGGSS
1536     The make syntax is difficult to parse without actually acting of the
1537     data.  For instance finding the end of a variable use should involve
1538     scanning each the modifiers using the correct terminator for each field.
1539     In many places make just counts {} and () in order to find the end of a
1540     variable expansion.
1541
1542     There is no way of escaping a space character in a filename.
1543
1544NetBSD 7.1_RC1                   June 22, 2017                  NetBSD 7.1_RC1
1545