11 058b0118 2005-01-03 devnull .if t .BR \\$1 \\$2
12 058b0118 2005-01-03 devnull .if n .RB ` \\$1 '\\$2
16 058b0118 2005-01-03 devnull .if t .B \\$1
17 058b0118 2005-01-03 devnull .if n .RB ` \\$1 '
20 058b0118 2005-01-03 devnull mk, membername \- maintain (make) related files
21 058b0118 2005-01-03 devnull .SH SYNOPSIS
25 058b0118 2005-01-03 devnull .I mkfile
28 058b0118 2005-01-03 devnull .I option ...
31 058b0118 2005-01-03 devnull .I target ...
34 058b0118 2005-01-03 devnull .B membername
35 058b0118 2005-01-03 devnull .IR lib ( object )
37 058b0118 2005-01-03 devnull .SH DESCRIPTION
39 058b0118 2005-01-03 devnull uses the dependency rules specified in
40 058b0118 2005-01-03 devnull .I mkfile
41 058b0118 2005-01-03 devnull to control the update (usually by compilation) of
42 058b0118 2005-01-03 devnull .I targets
43 058b0118 2005-01-03 devnull (usually files)
44 058b0118 2005-01-03 devnull from the source files upon which they depend.
46 058b0118 2005-01-03 devnull .I mkfile
48 058b0118 2005-01-03 devnull .LR mkfile )
49 058b0118 2005-01-03 devnull contains a
51 058b0118 2005-01-03 devnull for each target that identifies the files and other
52 058b0118 2005-01-03 devnull targets upon which it depends and an
53 058b0118 2005-01-03 devnull .IR sh (1)
54 058b0118 2005-01-03 devnull script, a
55 058b0118 2005-01-03 devnull .IR recipe ,
56 058b0118 2005-01-03 devnull to update the target.
57 058b0118 2005-01-03 devnull The script is run if the target does not exist
58 058b0118 2005-01-03 devnull or if it is older than any of the files it depends on.
59 058b0118 2005-01-03 devnull .I Mkfile
60 058b0118 2005-01-03 devnull may also contain
61 058b0118 2005-01-03 devnull .I meta-rules
62 058b0118 2005-01-03 devnull that define actions for updating implicit targets.
64 058b0118 2005-01-03 devnull .I target
65 058b0118 2005-01-03 devnull is specified, the target of the first rule (not meta-rule) in
66 058b0118 2005-01-03 devnull .I mkfile
67 058b0118 2005-01-03 devnull is updated.
69 058b0118 2005-01-03 devnull The environment variable
70 058b0118 2005-01-03 devnull .B $NPROC
71 058b0118 2005-01-03 devnull determines how many targets may be updated simultaneously;
72 058b0118 2005-01-03 devnull Some operating systems, e.g., Plan 9, set
73 058b0118 2005-01-03 devnull .B $NPROC
74 058b0118 2005-01-03 devnull automatically to the number of CPUs on the current machine.
76 058b0118 2005-01-03 devnull Options are:
77 058b0118 2005-01-03 devnull .TP \w'\fL-d[egp]\ 'u
79 058b0118 2005-01-03 devnull Assume all targets to be out of date.
80 058b0118 2005-01-03 devnull Thus, everything is updated.
83 058b0118 2005-01-03 devnull .BR -d [ egp ]
84 058b0118 2005-01-03 devnull Produce debugging output
86 058b0118 2005-01-03 devnull is for parsing,
88 058b0118 2005-01-03 devnull for graph building,
90 058b0118 2005-01-03 devnull for execution).
93 058b0118 2005-01-03 devnull Explain why each target is made.
96 058b0118 2005-01-03 devnull Force any missing intermediate targets to be made.
99 058b0118 2005-01-03 devnull Do as much work as possible in the face of errors.
102 058b0118 2005-01-03 devnull Print, but do not execute, the commands
103 058b0118 2005-01-03 devnull needed to update the targets.
106 058b0118 2005-01-03 devnull Make the command line arguments sequentially rather than in parallel.
109 058b0118 2005-01-03 devnull Touch (update the modified date of) file targets, without
110 058b0118 2005-01-03 devnull executing any recipes.
112 058b0118 2005-01-03 devnull .BI -w target1 , target2,...
113 058b0118 2005-01-03 devnull Pretend the modify time for each
114 058b0118 2005-01-03 devnull .I target
115 058b0118 2005-01-03 devnull is the current time; useful in conjunction with
117 058b0118 2005-01-03 devnull to learn what updates would be triggered by
118 058b0118 2005-01-03 devnull modifying the
119 058b0118 2005-01-03 devnull .IR targets .
121 058b0118 2005-01-03 devnull .SS The \fLmkfile\fP
123 058b0118 2005-01-03 devnull .I mkfile
124 058b0118 2005-01-03 devnull consists of
125 058b0118 2005-01-03 devnull .I assignments
126 058b0118 2005-01-03 devnull (described under `Environment') and
127 058b0118 2005-01-03 devnull .IR rules .
128 058b0118 2005-01-03 devnull A rule contains
129 058b0118 2005-01-03 devnull .I targets
131 058b0118 2005-01-03 devnull .IR tail .
132 058b0118 2005-01-03 devnull A target is a literal string
133 058b0118 2005-01-03 devnull and is normally a file name.
134 058b0118 2005-01-03 devnull The tail contains zero or more
135 058b0118 2005-01-03 devnull .I prerequisites
136 058b0118 2005-01-03 devnull and an optional
137 058b0118 2005-01-03 devnull .IR recipe ,
138 058b0118 2005-01-03 devnull which is an
139 058b0118 2005-01-03 devnull .B shell
141 058b0118 2005-01-03 devnull Each line of the recipe must begin with white space.
142 058b0118 2005-01-03 devnull A rule takes the form
145 058b0118 2005-01-03 devnull target: prereq1 prereq2
146 058b0118 2005-01-03 devnull \f2recipe using\fP prereq1, prereq2 \f2to build\fP target
149 058b0118 2005-01-03 devnull When the recipe is executed,
150 058b0118 2005-01-03 devnull the first character on every line is elided.
152 058b0118 2005-01-03 devnull After the colon on the target line, a rule may specify
153 058b0118 2005-01-03 devnull .IR attributes ,
154 058b0118 2005-01-03 devnull described below.
157 058b0118 2005-01-03 devnull .I meta-rule
158 058b0118 2005-01-03 devnull has a target of the form
159 058b0118 2005-01-03 devnull .IB A % B
164 058b0118 2005-01-03 devnull are (possibly empty) strings.
165 058b0118 2005-01-03 devnull A meta-rule acts as a rule for any potential target whose
166 058b0118 2005-01-03 devnull name matches
167 058b0118 2005-01-03 devnull .IB A % B
170 058b0118 2005-01-03 devnull replaced by an arbitrary string, called the
171 058b0118 2005-01-03 devnull .IR stem .
172 058b0118 2005-01-03 devnull In interpreting a meta-rule,
173 058b0118 2005-01-03 devnull the stem is substituted for all occurrences of
175 058b0118 2005-01-03 devnull in the prerequisite names.
176 058b0118 2005-01-03 devnull In the recipe of a meta-rule, the environment variable
177 058b0118 2005-01-03 devnull .B $stem
178 058b0118 2005-01-03 devnull contains the string matched by the
180 058b0118 2005-01-03 devnull For example, a meta-rule to compile a C program using
181 058b0118 2005-01-03 devnull .IR 9c (1)
182 058b0118 2005-01-03 devnull might be:
186 058b0118 2005-01-03 devnull 9c -c $stem.c
187 058b0118 2005-01-03 devnull 9l -o $stem $stem.o
190 058b0118 2005-01-03 devnull Meta-rules may contain an ampersand
192 058b0118 2005-01-03 devnull rather than a percent sign
196 058b0118 2005-01-03 devnull matches a maximal length string of any characters;
199 058b0118 2005-01-03 devnull matches a maximal length string of any characters except period
200 058b0118 2005-01-03 devnull or slash.
202 058b0118 2005-01-03 devnull The text of the
203 058b0118 2005-01-03 devnull .I mkfile
204 058b0118 2005-01-03 devnull is processed as follows.
205 058b0118 2005-01-03 devnull Lines beginning with
207 058b0118 2005-01-03 devnull followed by a file name are replaced by the contents of the named
209 058b0118 2005-01-03 devnull Lines beginning with
211 058b0118 2005-01-03 devnull followed by a file name are replaced by the output
212 058b0118 2005-01-03 devnull of the execution of the named
214 058b0118 2005-01-03 devnull Blank lines and comments, which run from unquoted
216 058b0118 2005-01-03 devnull characters to the following newline, are deleted.
217 058b0118 2005-01-03 devnull The character sequence backslash-newline is deleted,
218 058b0118 2005-01-03 devnull so long lines in
219 058b0118 2005-01-03 devnull .I mkfile
220 058b0118 2005-01-03 devnull may be folded.
221 058b0118 2005-01-03 devnull Non-recipe lines are processed by substituting for
222 058b0118 2005-01-03 devnull .BI `{ command }
223 058b0118 2005-01-03 devnull the output of the
224 058b0118 2005-01-03 devnull .I command
225 058b0118 2005-01-03 devnull when run by
226 058b0118 2005-01-03 devnull .IR sh .
227 058b0118 2005-01-03 devnull References to variables are replaced by the variables' values.
228 058b0118 2005-01-03 devnull Special characters may be quoted using single quotes
229 058b0118 2005-01-03 devnull .BR \&''
231 058b0118 2005-01-03 devnull .IR sh (1).
233 058b0118 2005-01-03 devnull Assignments and rules are distinguished by
234 058b0118 2005-01-03 devnull the first unquoted occurrence of
239 058b0118 2005-01-03 devnull (assignment).
241 058b0118 2005-01-03 devnull A later rule may modify or override an existing rule under the
242 058b0118 2005-01-03 devnull following conditions:
245 058b0118 2005-01-03 devnull If the targets of the rules exactly match and one rule
246 058b0118 2005-01-03 devnull contains only a prerequisite clause and no recipe, the
247 058b0118 2005-01-03 devnull clause is added to the prerequisites of the other rule.
248 058b0118 2005-01-03 devnull If either or both targets are virtual, the recipe is
249 058b0118 2005-01-03 devnull always executed.
252 058b0118 2005-01-03 devnull If the targets of the rules match exactly and the
253 058b0118 2005-01-03 devnull prerequisites do not match and both rules
254 058b0118 2005-01-03 devnull contain recipes,
256 058b0118 2005-01-03 devnull reports an ``ambiguous recipe'' error.
259 058b0118 2005-01-03 devnull If the target and prerequisites of both rules match exactly,
260 058b0118 2005-01-03 devnull the second rule overrides the first.
261 058b0118 2005-01-03 devnull .SS Environment
262 058b0118 2005-01-03 devnull Rules may make use of
264 058b0118 2005-01-03 devnull environment variables.
265 058b0118 2005-01-03 devnull A legal reference of the form
268 058b0118 2005-01-03 devnull .B ${name}
269 058b0118 2005-01-03 devnull is expanded as in
270 058b0118 2005-01-03 devnull .IR sh (1).
271 058b0118 2005-01-03 devnull A reference of the form
272 058b0118 2005-01-03 devnull .BI ${name: A % B = C\fL%\fID\fL}\fR,
274 058b0118 2005-01-03 devnull .I A, B, C, D
275 058b0118 2005-01-03 devnull are (possibly empty) strings,
276 058b0118 2005-01-03 devnull has the value formed by expanding
277 058b0118 2005-01-03 devnull .B $name
278 058b0118 2005-01-03 devnull and substituting
286 058b0118 2005-01-03 devnull in each word in
287 058b0118 2005-01-03 devnull .B $name
288 058b0118 2005-01-03 devnull that matches pattern
289 058b0118 2005-01-03 devnull .IB A % B\f1.
291 058b0118 2005-01-03 devnull Variables can be set by
292 058b0118 2005-01-03 devnull assignments of the form
294 058b0118 2005-01-03 devnull var\fL=\fR[\fIattr\fL=\fR]\fIvalue\fR
296 058b0118 2005-01-03 devnull Blanks in the
297 058b0118 2005-01-03 devnull .I value
298 058b0118 2005-01-03 devnull break it into words.
299 058b0118 2005-01-03 devnull Such variables are exported
300 058b0118 2005-01-03 devnull to the environment of
301 058b0118 2005-01-03 devnull recipes as they are executed, unless
303 058b0118 2005-01-03 devnull the only legal attribute
304 058b0118 2005-01-03 devnull .IR attr ,
305 058b0118 2005-01-03 devnull is present.
306 058b0118 2005-01-03 devnull The initial value of a variable is
307 058b0118 2005-01-03 devnull taken from (in increasing order of precedence)
308 058b0118 2005-01-03 devnull the default values below,
310 058b0118 2005-01-03 devnull environment, the
311 058b0118 2005-01-03 devnull .IR mkfiles ,
312 058b0118 2005-01-03 devnull and any command line assignment as an argument to
313 058b0118 2005-01-03 devnull .IR mk .
314 058b0118 2005-01-03 devnull A variable assignment argument overrides the first (but not any subsequent)
315 058b0118 2005-01-03 devnull assignment to that variable.
316 058b0118 2005-01-03 devnull The variable
317 058b0118 2005-01-03 devnull .B MKFLAGS
318 058b0118 2005-01-03 devnull contains all the option arguments (arguments starting with
320 058b0118 2005-01-03 devnull or containing
323 058b0118 2005-01-03 devnull .B MKARGS
324 058b0118 2005-01-03 devnull contains all the targets in the call to
325 058b0118 2005-01-03 devnull .IR mk .
327 058b0118 2005-01-03 devnull Dynamic information may be included in the mkfile by using a line of the form
329 058b0118 2005-01-03 devnull \fR<|\fIcommand\fR \fIargs\fR
331 058b0118 2005-01-03 devnull This runs the command
332 058b0118 2005-01-03 devnull .I command
333 058b0118 2005-01-03 devnull with the given arguments
335 058b0118 2005-01-03 devnull and pipes its standard output to
337 058b0118 2005-01-03 devnull to be included as part of the mkfile. For instance, the Inferno kernels
338 058b0118 2005-01-03 devnull use this technique
339 058b0118 2005-01-03 devnull to run a shell command with an awk script and a configuration
340 058b0118 2005-01-03 devnull file as arguments in order for
343 058b0118 2005-01-03 devnull script to process the file and output a set of variables and their values.
344 058b0118 2005-01-03 devnull .SS Execution
346 058b0118 2005-01-03 devnull During execution,
348 058b0118 2005-01-03 devnull determines which targets must be updated, and in what order,
349 058b0118 2005-01-03 devnull to build the
350 058b0118 2005-01-03 devnull .I names
351 058b0118 2005-01-03 devnull specified on the command line.
352 058b0118 2005-01-03 devnull It then runs the associated recipes.
354 058b0118 2005-01-03 devnull A target is considered up to date if it has no prerequisites or
355 058b0118 2005-01-03 devnull if all its prerequisites are up to date and it is newer
356 058b0118 2005-01-03 devnull than all its prerequisites.
357 058b0118 2005-01-03 devnull Once the recipe for a target has executed, the target is
358 058b0118 2005-01-03 devnull considered up to date.
360 058b0118 2005-01-03 devnull The date stamp
361 058b0118 2005-01-03 devnull used to determine if a target is up to date is computed
362 058b0118 2005-01-03 devnull differently for different types of targets.
363 058b0118 2005-01-03 devnull If a target is
364 058b0118 2005-01-03 devnull .I virtual
365 058b0118 2005-01-03 devnull (the target of a rule with the
367 058b0118 2005-01-03 devnull attribute),
368 058b0118 2005-01-03 devnull its date stamp is initially zero; when the target is
369 058b0118 2005-01-03 devnull updated the date stamp is set to
370 058b0118 2005-01-03 devnull the most recent date stamp of its prerequisites.
371 058b0118 2005-01-03 devnull Otherwise, if a target does not exist as a file,
372 058b0118 2005-01-03 devnull its date stamp is set to the most recent date stamp of its prerequisites,
373 058b0118 2005-01-03 devnull or zero if it has no prerequisites.
374 058b0118 2005-01-03 devnull Otherwise, the target is the name of a file and
375 058b0118 2005-01-03 devnull the target's date stamp is always that file's modification date.
376 058b0118 2005-01-03 devnull The date stamp is computed when the target is needed in
377 058b0118 2005-01-03 devnull the execution of a rule; it is not a static value.
379 058b0118 2005-01-03 devnull Nonexistent targets that have prerequisites
380 058b0118 2005-01-03 devnull and are themselves prerequisites are treated specially.
381 058b0118 2005-01-03 devnull Such a target
383 058b0118 2005-01-03 devnull is given the date stamp of its most recent prerequisite
384 058b0118 2005-01-03 devnull and if this causes all the targets which have
386 058b0118 2005-01-03 devnull as a prerequisite to be up to date,
388 058b0118 2005-01-03 devnull is considered up to date.
389 058b0118 2005-01-03 devnull Otherwise,
391 058b0118 2005-01-03 devnull is made in the normal fashion.
394 058b0118 2005-01-03 devnull flag overrides this special treatment.
396 058b0118 2005-01-03 devnull Files may be made in any order that respects
397 058b0118 2005-01-03 devnull the preceding restrictions.
399 058b0118 2005-01-03 devnull A recipe is executed by supplying the recipe as standard input to
400 058b0118 2005-01-03 devnull the command
401 058b0118 2005-01-03 devnull .BR /bin/sh .
402 058b0118 2005-01-03 devnull (Note that unlike
403 058b0118 2005-01-03 devnull .IR make ,
405 058b0118 2005-01-03 devnull feeds the entire recipe to the shell rather than running each line
406 058b0118 2005-01-03 devnull of the recipe separately.)
407 058b0118 2005-01-03 devnull The environment is augmented by the following variables:
409 058b0118 2005-01-03 devnull .B $alltarget
410 058b0118 2005-01-03 devnull all the targets of this rule.
412 058b0118 2005-01-03 devnull .B $newprereq
413 058b0118 2005-01-03 devnull the prerequisites that caused this rule to execute.
415 058b0118 2005-01-03 devnull .B $newmember
416 058b0118 2005-01-03 devnull the prerequisites that are members of an aggregate
417 058b0118 2005-01-03 devnull that caused this rule to execute.
418 058b0118 2005-01-03 devnull When the prerequisites of a rule are members of an
419 058b0118 2005-01-03 devnull aggregate,
420 058b0118 2005-01-03 devnull .B $newprereq
421 058b0118 2005-01-03 devnull contains the name of the aggregate and out of date
422 058b0118 2005-01-03 devnull members, while
423 058b0118 2005-01-03 devnull .B $newmember
424 058b0118 2005-01-03 devnull contains only the name of the members.
426 058b0118 2005-01-03 devnull .B $nproc
427 058b0118 2005-01-03 devnull the process slot for this recipe.
428 058b0118 2005-01-03 devnull It satisfies
429 058b0118 2005-01-03 devnull .RB 0≤ $nproc < $NPROC .
432 058b0118 2005-01-03 devnull the process id for the
434 058b0118 2005-01-03 devnull executing the recipe.
436 058b0118 2005-01-03 devnull .B $prereq
437 058b0118 2005-01-03 devnull all the prerequisites for this rule.
439 058b0118 2005-01-03 devnull .B $stem
440 058b0118 2005-01-03 devnull if this is a meta-rule,
441 058b0118 2005-01-03 devnull .B $stem
442 058b0118 2005-01-03 devnull is the string that matched
446 058b0118 2005-01-03 devnull Otherwise, it is empty.
447 058b0118 2005-01-03 devnull For regular expression meta-rules (see below), the variables
448 058b0118 2005-01-03 devnull .LR stem0 ", ...,"
449 058b0118 2005-01-03 devnull .L stem9
450 058b0118 2005-01-03 devnull are set to the corresponding subexpressions.
452 058b0118 2005-01-03 devnull .B $target
453 058b0118 2005-01-03 devnull the targets for this rule that need to be remade.
455 058b0118 2005-01-03 devnull These variables are available only during the execution of a recipe,
456 058b0118 2005-01-03 devnull not while evaluating the
457 058b0118 2005-01-03 devnull .IR mkfile .
459 058b0118 2005-01-03 devnull Unless the rule has the
461 058b0118 2005-01-03 devnull attribute,
462 058b0118 2005-01-03 devnull the recipe is printed prior to execution
463 058b0118 2005-01-03 devnull with recognizable environment variables expanded.
464 058b0118 2005-01-03 devnull Commands returning error status
467 058b0118 2005-01-03 devnull to terminate.
469 058b0118 2005-01-03 devnull Recipes and backquoted
471 058b0118 2005-01-03 devnull commands in places such as assignments
472 058b0118 2005-01-03 devnull execute in a copy of
474 058b0118 2005-01-03 devnull environment; changes they make to
475 058b0118 2005-01-03 devnull environment variables are not visible from
476 058b0118 2005-01-03 devnull .IR mk .
478 058b0118 2005-01-03 devnull Variable substitution in a rule is done when
479 058b0118 2005-01-03 devnull the rule is read; variable substitution in the recipe is done
480 058b0118 2005-01-03 devnull when the recipe is executed. For example:
484 058b0118 2005-01-03 devnull foo: $bar
485 058b0118 2005-01-03 devnull $CC -o foo $bar
489 058b0118 2005-01-03 devnull will compile
492 058b0118 2005-01-03 devnull .BR foo ,
495 058b0118 2005-01-03 devnull is newer than
496 058b0118 2005-01-03 devnull .BR foo .
497 058b0118 2005-01-03 devnull .SS Aggregates
498 058b0118 2005-01-03 devnull Names of the form
499 058b0118 2005-01-03 devnull .IR a ( b )
500 058b0118 2005-01-03 devnull refer to member
502 058b0118 2005-01-03 devnull of the aggregate
504 058b0118 2005-01-03 devnull Currently, the only aggregates supported are
507 058b0118 2005-01-03 devnull .IR 9c (1))
508 058b0118 2005-01-03 devnull archives.
510 058b0118 2005-01-03 devnull .I Membername
511 058b0118 2005-01-03 devnull echoes just the member names of a list of aggregate names.
512 058b0118 2005-01-03 devnull It is useful in recipes like:
514 058b0118 2005-01-03 devnull OFILES=a.o b.o
515 058b0118 2005-01-03 devnull libc.a(%):N: %
516 058b0118 2005-01-03 devnull libc.a: ${OFILES:%=libc.a(%)}
517 058b0118 2005-01-03 devnull 9ar rvc libc.a `membername $newprereq`
519 058b0118 2005-01-03 devnull which re-archives only the new object files.
520 058b0118 2005-01-03 devnull .SS Attributes
521 058b0118 2005-01-03 devnull The colon separating the target from the prerequisites
523 058b0118 2005-01-03 devnull immediately followed by
524 058b0118 2005-01-03 devnull .I attributes
525 058b0118 2005-01-03 devnull and another colon.
526 058b0118 2005-01-03 devnull The attributes are:
529 058b0118 2005-01-03 devnull If the recipe exits with a non-null status, the target is deleted.
532 058b0118 2005-01-03 devnull Continue execution if the recipe draws errors.
535 058b0118 2005-01-03 devnull If there is no recipe, the target has its time updated.
538 058b0118 2005-01-03 devnull The rule is a meta-rule that cannot be a target of a virtual rule.
539 058b0118 2005-01-03 devnull Only files match the pattern in the target.
542 058b0118 2005-01-03 devnull The characters after the
544 058b0118 2005-01-03 devnull until the terminating
546 058b0118 2005-01-03 devnull are taken as a program name.
547 058b0118 2005-01-03 devnull It will be invoked as
548 058b0118 2005-01-03 devnull .B "sh -c prog 'arg1' 'arg2'"
549 058b0118 2005-01-03 devnull and should return a zero exit status
550 058b0118 2005-01-03 devnull if and only if arg1 is up to date with respect to arg2.
551 058b0118 2005-01-03 devnull Date stamps are still propagated in the normal way.
554 058b0118 2005-01-03 devnull The recipe is not printed prior to execution.
557 058b0118 2005-01-03 devnull The rule is a meta-rule using regular expressions.
558 058b0118 2005-01-03 devnull In the rule,
560 058b0118 2005-01-03 devnull has no special meaning.
561 058b0118 2005-01-03 devnull The target is interpreted as a regular expression as defined in
562 058b0118 2005-01-03 devnull .IR regexp (7).
563 058b0118 2005-01-03 devnull The prerequisites may contain references
564 058b0118 2005-01-03 devnull to subexpressions in form
565 058b0118 2005-01-03 devnull .BI \e n\f1,
566 058b0118 2005-01-03 devnull as in the substitute command of
567 058b0118 2005-01-03 devnull .IR sed (1).
570 058b0118 2005-01-03 devnull The targets are considered to have been updated
571 058b0118 2005-01-03 devnull even if the recipe did not do so.
574 058b0118 2005-01-03 devnull The targets of this rule are marked as virtual.
575 058b0118 2005-01-03 devnull They are distinct from files of the same name.
577 058b0118 2005-01-03 devnull .SH EXAMPLES
578 058b0118 2005-01-03 devnull A simple mkfile to compile a program:
581 058b0118 2005-01-03 devnull .ta 8n +8n +8n +8n +8n +8n +8n
582 058b0118 2005-01-03 devnull </$objtype/mkfile
584 058b0118 2005-01-03 devnull prog: a.$O b.$O c.$O
585 058b0118 2005-01-03 devnull $LD $LDFLAGS -o $target $prereq
587 058b0118 2005-01-03 devnull %.$O: %.c
588 058b0118 2005-01-03 devnull $CC $CFLAGS $stem.c
591 058b0118 2005-01-03 devnull Override flag settings in the mkfile:
594 058b0118 2005-01-03 devnull % mk target 'CFLAGS=-S -w'
597 058b0118 2005-01-03 devnull Maintain a library:
600 058b0118 2005-01-03 devnull libc.a(%.$O):N: %.$O
601 058b0118 2005-01-03 devnull libc.a: libc.a(abs.$O) libc.a(access.$O) libc.a(alarm.$O) ...
602 058b0118 2005-01-03 devnull ar r libc.a $newmember
605 058b0118 2005-01-03 devnull String expression variables to derive names from a master list:
608 058b0118 2005-01-03 devnull NAMES=alloc arc bquote builtins expand main match mk var word
609 058b0118 2005-01-03 devnull OBJ=${NAMES:%=%.$O}
612 058b0118 2005-01-03 devnull Regular expression meta-rules:
615 058b0118 2005-01-03 devnull ([^/]*)/(.*)\e.$O:R: \e1/\e2.c
616 058b0118 2005-01-03 devnull cd $stem1; $CC $CFLAGS $stem2.c
619 058b0118 2005-01-03 devnull A correct way to deal with
620 058b0118 2005-01-03 devnull .IR yacc (1)
621 058b0118 2005-01-03 devnull grammars.
622 058b0118 2005-01-03 devnull The file
623 058b0118 2005-01-03 devnull .B lex.c
624 058b0118 2005-01-03 devnull includes the file
625 058b0118 2005-01-03 devnull .B x.tab.h
626 058b0118 2005-01-03 devnull rather than
627 058b0118 2005-01-03 devnull .B y.tab.h
628 058b0118 2005-01-03 devnull in order to reflect changes in content, not just modification time.
631 058b0118 2005-01-03 devnull lex.$O: x.tab.h
632 058b0118 2005-01-03 devnull x.tab.h: y.tab.h
633 058b0118 2005-01-03 devnull cmp -s x.tab.h y.tab.h || cp y.tab.h x.tab.h
634 058b0118 2005-01-03 devnull y.tab.c y.tab.h: gram.y
635 058b0118 2005-01-03 devnull $YACC -d gram.y
638 058b0118 2005-01-03 devnull The above example could also use the
640 058b0118 2005-01-03 devnull attribute for the
641 058b0118 2005-01-03 devnull .B x.tab.h
645 058b0118 2005-01-03 devnull x.tab.h:Pcmp -s: y.tab.h
646 058b0118 2005-01-03 devnull cp y.tab.h x.tab.h
648 058b0118 2005-01-03 devnull .SH SEE ALSO
649 058b0118 2005-01-03 devnull .IR sh (1),
650 058b0118 2005-01-03 devnull .IR regexp9 (7)
652 058b0118 2005-01-03 devnull A. Hume,
653 058b0118 2005-01-03 devnull ``Mk: a Successor to Make''
654 058b0118 2005-01-03 devnull (Tenth Edition Research Unix Manuals).
656 058b0118 2005-01-03 devnull Andrew G. Hume and Bob Flandrena,
657 058b0118 2005-01-03 devnull ``Maintaining Files on Plan 9 with Mk''.
658 058b0118 2005-01-03 devnull DOCPREFIX/doc/mk.pdf
659 058b0118 2005-01-03 devnull .SH HISTORY
660 058b0118 2005-01-03 devnull Andrew Hume wrote
662 058b0118 2005-01-03 devnull for Tenth Edition Research Unix.
663 058b0118 2005-01-03 devnull It was later ported to Plan 9.
664 058b0118 2005-01-03 devnull This software is a port of the Plan 9 version back to Unix.
665 058b0118 2005-01-03 devnull .SH BUGS
666 058b0118 2005-01-03 devnull Identical recipes for regular expression meta-rules only have one target.
668 058b0118 2005-01-03 devnull Seemingly appropriate input like
669 058b0118 2005-01-03 devnull .B CFLAGS=-DHZ=60
670 058b0118 2005-01-03 devnull is parsed as an erroneous attribute; correct it by inserting
671 058b0118 2005-01-03 devnull a space after the first
674 058b0118 2005-01-03 devnull The recipes printed by
676 058b0118 2005-01-03 devnull before being passed to
678 058b0118 2005-01-03 devnull for execution are sometimes erroneously expanded
679 058b0118 2005-01-03 devnull for printing. Don't trust what's printed; rely
