summaryrefslogtreecommitdiff
path: root/src/engine/SCons/Script/Main.xml
blob: b0cf5ed452ba1189d821b03ef754b66d0a3257aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
<?xml version="1.0" encoding="UTF-8"?>
<!--
Copyright (c) 2001 - 2015 The SCons Foundation

This file is processed by the bin/SConsDoc.py module.
See its __doc__ string for a discussion of the format.
-->

<!DOCTYPE sconsdoc [
<!ENTITY % scons SYSTEM '../../../../doc/scons.mod'>
%scons;
<!ENTITY % builders-mod SYSTEM '../../../../doc/generated/builders.mod'>
%builders-mod;
<!ENTITY % functions-mod SYSTEM '../../../../doc/generated/functions.mod'>
%functions-mod;
<!ENTITY % tools-mod SYSTEM '../../../../doc/generated/tools.mod'>
%tools-mod;
<!ENTITY % variables-mod SYSTEM '../../../../doc/generated/variables.mod'>
%variables-mod;
]>

<sconsdoc xmlns="http://www.scons.org/dbxsd/v1.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://www.scons.org/dbxsd/v1.0 http://www.scons.org/dbxsd/v1.0/scons.xsd">


<scons_function name="AddOption">
<arguments signature="global">
(arguments)
</arguments>
<summary>
<para>
This function adds a new command-line option to be recognized.
The specified
<varname>arguments</varname>
are the same as supported by the standard Python
<function>optparse.add_option</function>()
method (with a few additional capabilities noted below);
see the documentation for
<literal>optparse</literal>
for a thorough discussion of its option-processing capabities.
</para>

<para>
In addition to the arguments and values supported by the
<function>optparse.add_option</function>()
method,
the SCons
&f-AddOption;
function allows you to set the
<literal>nargs</literal>
keyword value to
<literal>'?'</literal>
(a string with just the question mark)
to indicate that the specified long option(s) take(s) an
<emphasis>optional</emphasis>
argument.
When
<literal>nargs = '?'</literal>
is passed to the
&f-AddOption;
function, the
<literal>const</literal>
keyword argument
may be used to supply the "default"
value that should be used when the
option is specified on the command line
without an explicit argument.
</para>

<para>
If no
<literal>default=</literal>
keyword argument is supplied when calling
&f-AddOption;,
the option will have a default value of
<literal>None</literal>.
</para>

<para>
Once a new command-line option has been added with
&f-AddOption;,
the option value may be accessed using
&f-GetOption;
or
<function>env.GetOption</function>().
The value may also be set, using
&f-SetOption;
or
<function>env.SetOption</function>(),
if conditions in a
&SConscript;
require overriding any default value.
Note, however, that a
value specified on the command line will
<emphasis>always</emphasis>
override a value set by any SConscript file.
</para>

<para>
Any specified
<literal>help=</literal>
strings for the new option(s)
will be displayed by the
<option>-H</option>
or
<option>-h</option>
options
(the latter only if no other help text is
specified in the SConscript files).
The help text for the local options specified by
&f-AddOption;
will appear below the SCons options themselves,
under a separate
<literal>Local Options</literal>
heading.
The options will appear in the help text
in the order in which the
&f-AddOption;
calls occur.
</para>

<para>
Example:
</para>

<example_commands>
AddOption('--prefix',
          dest='prefix',
          nargs=1, type='string',
          action='store',
          metavar='DIR',
          help='installation prefix')
env = Environment(PREFIX = GetOption('prefix'))
</example_commands>
</summary>
</scons_function>

<scons_function name="GetBuildFailures">
<arguments signature="global">
()
</arguments>
<summary>
<para>
Returns a list of exceptions for the
actions that failed while
attempting to build targets.
Each element in the returned list is a
<classname>BuildError</classname>
object
with the following attributes
that record various aspects
of the build failure:
</para>

<para>
<literal>.node</literal>
The node that was being built
when the build failure occurred.
</para>

<para>
<literal>.status</literal>
The numeric exit status
returned by the command or Python function
that failed when trying to build the
specified Node.
</para>

<para>
<literal>.errstr</literal>
The SCons error string
describing the build failure.
(This is often a generic
message like "Error 2"
to indicate that an executed
command exited with a status of 2.)
</para>

<para>
<literal>.filename</literal>
The name of the file or
directory that actually caused the failure.
This may be different from the
<literal>.node</literal>
attribute.
For example,
if an attempt to build a target named
<filename>sub/dir/target</filename>
fails because the
<filename>sub/dir</filename>
directory could not be created,
then the
<literal>.node</literal>
attribute will be
<filename>sub/dir/target</filename>
but the
<literal>.filename</literal>
attribute will be
<filename>sub/dir</filename>.
</para>

<para>
<literal>.executor</literal>
The SCons Executor object
for the target Node
being built.
This can be used to retrieve
the construction environment used
for the failed action.
</para>

<para>
<literal>.action</literal>
The actual SCons Action object that failed.
This will be one specific action
out of the possible list of
actions that would have been
executed to build the target.
</para>

<para>
<literal>.command</literal>
The actual expanded command that was executed and failed,
after expansion of
&cv-link-TARGET;,
&cv-link-SOURCE;,
and other construction variables.
</para>

<para>
Note that the
&f-GetBuildFailures;
function
will always return an empty list
until any build failure has occurred,
which means that
&f-GetBuildFailures;
will always return an empty list
while the
&SConscript;
files are being read.
Its primary intended use is
for functions that will be
executed before SCons exits
by passing them to the
standard Python
<function>atexit.register</function>()
function.
Example:
</para>

<example_commands>
import atexit

def print_build_failures():
    from SCons.Script import GetBuildFailures
    for bf in GetBuildFailures():
        print "%s failed: %s" % (bf.node, bf.errstr)

atexit.register(print_build_failures)
</example_commands>
</summary>
</scons_function>

<scons_function name="GetOption">
<arguments>
(name)
</arguments>
<summary>
<para>
This function provides a way to query the value of
SCons options set on scons command line
(or set using the
&f-link-SetOption;
function).
The options supported are:
</para>

<para>
<variablelist>
<varlistentry>
<term><literal>cache_debug</literal></term>
<listitem>
<para>
which corresponds to --cache-debug;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>cache_disable</literal></term>
<listitem>
<para>
which corresponds to --cache-disable;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>cache_force</literal></term>
<listitem>
<para>
which corresponds to --cache-force;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>cache_show</literal></term>
<listitem>
<para>
which corresponds to --cache-show;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>clean</literal></term>
<listitem>
<para>
which corresponds to -c, --clean and --remove;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>config</literal></term>
<listitem>
<para>
which corresponds to --config;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>directory</literal></term>
<listitem>
<para>
which corresponds to -C and --directory;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>diskcheck</literal></term>
<listitem>
<para>
which corresponds to --diskcheck
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>duplicate</literal></term>
<listitem>
<para>
which corresponds to --duplicate;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>file</literal></term>
<listitem>
<para>
which corresponds to -f, --file, --makefile and --sconstruct;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>help</literal></term>
<listitem>
<para>
which corresponds to -h and --help;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>ignore_errors</literal></term>
<listitem>
<para>
which corresponds to --ignore-errors;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>implicit_cache</literal></term>
<listitem>
<para>
which corresponds to --implicit-cache;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>implicit_deps_changed</literal></term>
<listitem>
<para>
which corresponds to --implicit-deps-changed;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>implicit_deps_unchanged</literal></term>
<listitem>
<para>
which corresponds to --implicit-deps-unchanged;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>interactive</literal></term>
<listitem>
<para>
which corresponds to --interact and --interactive;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>keep_going</literal></term>
<listitem>
<para>
which corresponds to -k and --keep-going;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>max_drift</literal></term>
<listitem>
<para>
which corresponds to --max-drift;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>no_exec</literal></term>
<listitem>
<para>
which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>no_site_dir</literal></term>
<listitem>
<para>
which corresponds to --no-site-dir;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>num_jobs</literal></term>
<listitem>
<para>
which corresponds to -j and --jobs;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>profile_file</literal></term>
<listitem>
<para>
which corresponds to --profile;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>question</literal></term>
<listitem>
<para>
which corresponds to -q and --question;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>random</literal></term>
<listitem>
<para>
which corresponds to --random;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>repository</literal></term>
<listitem>
<para>
which corresponds to -Y, --repository and --srcdir;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>silent</literal></term>
<listitem>
<para>
which corresponds to -s, --silent and --quiet;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>site_dir</literal></term>
<listitem>
<para>
which corresponds to --site-dir;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>stack_size</literal></term>
<listitem>
<para>
which corresponds to --stack-size;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>taskmastertrace_file</literal></term>
<listitem>
<para>
which corresponds to --taskmastertrace; and
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>warn</literal></term>
<listitem>
<para>
which corresponds to --warn and --warning.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>

<para>
See the documentation for the
corresponding command line object for information about each specific
option.
</para>
</summary>
</scons_function>

<scons_function name="Progress">
<arguments signature="global">
(callable, [interval])
</arguments>
<arguments signature="global">
(string, [interval, file, overwrite])
</arguments>
<arguments signature="global">
(list_of_strings, [interval, file, overwrite])
</arguments>
<summary>
<para>
Allows SCons to show progress made during the build
by displaying a string or calling a function while
evaluating Nodes (e.g. files).
</para>

<para>
If the first specified argument is a Python callable
(a function or an object that has a
<function>__call__</function>()
method),
the function will be called
once every
<varname>interval</varname>
times a Node is evaluated.
The callable will be passed the evaluated Node
as its only argument.
(For future compatibility,
it's a good idea to also add
<literal>*args</literal>
and
<literal>**kw</literal>
as arguments to your function or method.
This will prevent the code from breaking
if SCons ever changes the interface
to call the function with additional arguments in the future.)
</para>

<para>
An example of a simple custom progress function
that prints a string containing the Node name
every 10 Nodes:
</para>

<example_commands>
def my_progress_function(node, *args, **kw):
    print 'Evaluating node %s!' % node
Progress(my_progress_function, interval=10)
</example_commands>

<para>
A more complicated example of a custom progress display object
that prints a string containing a count
every 100 evaluated Nodes.
Note the use of
<literal>\r</literal>
(a carriage return)
at the end so that the string
will overwrite itself on a display:
</para>

<example_commands>
import sys
class ProgressCounter(object):
    count = 0
    def __call__(self, node, *args, **kw):
        self.count += 100
        sys.stderr.write('Evaluated %s nodes\r' % self.count)
Progress(ProgressCounter(), interval=100)
</example_commands>

<para>
If the first argument
&f-link-Progress;
is a string,
the string will be displayed
every
<varname>interval</varname>
evaluated Nodes.
The default is to print the string on standard output;
an alternate output stream
may be specified with the
<literal>file=</literal>
argument.
The following will print a series of dots
on the error output,
one dot for every 100 evaluated Nodes:
</para>

<example_commands>
import sys
Progress('.', interval=100, file=sys.stderr)
</example_commands>

<para>
If the string contains the verbatim substring
&cv-TARGET;,
it will be replaced with the Node.
Note that, for performance reasons, this is
<emphasis>not</emphasis>
a regular SCons variable substition,
so you can not use other variables
or use curly braces.
The following example will print the name of
every evaluated Node,
using a
<literal>\r</literal>
(carriage return) to cause each line to overwritten by the next line,
and the
<literal>overwrite=</literal>
keyword argument to make sure the previously-printed
file name is overwritten with blank spaces:
</para>

<example_commands>
import sys
Progress('$TARGET\r', overwrite=True)
</example_commands>

<para>
If the first argument to
&f-Progress;
is a list of strings,
then each string in the list will be displayed
in rotating fashion every
<varname>interval</varname>
evaluated Nodes.
This can be used to implement a "spinner"
on the user's screen as follows:
</para>

<example_commands>
Progress(['-\r', '\\\r', '|\r', '/\r'], interval=5)
</example_commands>
</summary>
</scons_function>

<scons_function name="Precious">
<arguments>
(target, ...)
</arguments>
<summary>
<para>
Marks each given
<varname>target</varname>
as precious so it is not deleted before it is rebuilt. Normally
&scons;
deletes a target before building it.
Multiple targets can be passed in to a single call to
&f-Precious;.
</para>
</summary>
</scons_function>

<scons_function name="Pseudo">
<arguments>
(target, ...)
</arguments>
<summary>
<para>
This indicates that each given
<varname>target</varname>
should not be created by the build rule, and if the target is created,
an error will be generated. This is similar to the gnu make .PHONY
target. However, in the vast majority of cases, an
&f-Alias;
is more appropriate.

Multiple targets can be passed in to a single call to
&f-Pseudo;.
</para>
</summary>
</scons_function>
<scons_function name="SetOption">
<arguments>
(name, value)
</arguments>
<summary>
<para>
This function provides a way to set a select subset of the scons command
line options from a SConscript file. The options supported are:
</para>

<para>
<variablelist>
<varlistentry>
<term><literal>clean</literal></term>
<listitem>
<para>
which corresponds to -c, --clean and --remove;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>duplicate</literal></term>
<listitem>
<para>
which corresponds to --duplicate;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>help</literal></term>
<listitem>
<para>
which corresponds to -h and --help;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>implicit_cache</literal></term>
<listitem>
<para>
which corresponds to --implicit-cache;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>max_drift</literal></term>
<listitem>
<para>
which corresponds to --max-drift;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>no_exec</literal></term>
<listitem>
<para>
which corresponds to -n, --no-exec, --just-print, --dry-run and --recon;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>num_jobs</literal></term>
<listitem>
<para>
which corresponds to -j and --jobs;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>random</literal></term>
<listitem>
<para>
which corresponds to --random; and
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>stack_size</literal></term>
<listitem>
<para>
which corresponds to --stack-size.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>

<para>
See the documentation for the
corresponding command line object for information about each specific
option.
</para>

<para>
Example:
</para>

<example_commands>
SetOption('max_drift', 1)
</example_commands>
</summary>
</scons_function>

</sconsdoc>