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Revision: 1.7
Committed: Wed Dec 8 22:27:35 2010 UTC (13 years, 5 months ago) by root
Branch: MAIN
CVS Tags: rel-0_9
Changes since 1.6: +34 -0 lines
Log Message:
0.9

File Contents

# Content
1 NAME
2 staticperl - perl, libc, 100 modules, all in one 500kb file
3
4 SYNOPSIS
5 staticperl help # print the embedded documentation
6 staticperl fetch # fetch and unpack perl sources
7 staticperl configure # fetch and then configure perl
8 staticperl build # configure and then build perl
9 staticperl install # build and then install perl
10 staticperl clean # clean most intermediate files (restart at configure)
11 staticperl distclean # delete everything installed by this script
12 staticperl cpan # invoke CPAN shell
13 staticperl instmod path... # install unpacked modules
14 staticperl instcpan modulename... # install modules from CPAN
15 staticperl mkbundle <bundle-args...> # see documentation
16 staticperl mkperl <bundle-args...> # see documentation
17 staticperl mkapp appname <bundle-args...> # see documentation
18
19 Typical Examples:
20
21 staticperl install # fetch, configure, build and install perl
22 staticperl cpan # run interactive cpan shell
23 staticperl mkperl -M '"Config_heavy.pl"' # build a perl that supports -V
24 staticperl mkperl -MAnyEvent::Impl::Perl -MAnyEvent::HTTPD -MURI -MURI::http
25 # build a perl with the above modules linked in
26 staticperl mkapp myapp --boot mainprog mymodules
27 # build a binary "myapp" from mainprog and mymodules
28
29 DESCRIPTION
30 This script helps you creating single-file perl interpreters, or
31 embedding a perl interpreter in your applications. Single-file means
32 that it is fully self-contained - no separate shared objects, no
33 autoload fragments, no .pm or .pl files are needed. And when linking
34 statically, you can create (or embed) a single file that contains perl
35 interpreter, libc, all the modules you need and all the libraries you
36 need.
37
38 With uClibc and upx on x86, you can create a single 500kb binary that
39 contains perl and 100 modules such as POSIX, AnyEvent, EV, IO::AIO, Coro
40 and so on. Or any other choice of modules.
41
42 The created files do not need write access to the file system (like PAR
43 does). In fact, since this script is in many ways similar to
44 PAR::Packer, here are the differences:
45
46 * The generated executables are much smaller than PAR created ones.
47
48 Shared objects and the perl binary contain a lot of extra info,
49 while the static nature of staticperl allows the linker to remove
50 all functionality and meta-info not required by the final
51 executable. Even extensions statically compiled into perl at build
52 time will only be present in the final executable when needed.
53
54 In addition, staticperl can strip perl sources much more effectively
55 than PAR.
56
57 * The generated executables start much faster.
58
59 There is no need to unpack files, or even to parse Zip archives
60 (which is slow and memory-consuming business).
61
62 * The generated executables don't need a writable filesystem.
63
64 staticperl loads all required files directly from memory. There is
65 no need to unpack files into a temporary directory.
66
67 * More control over included files.
68
69 PAR tries to be maintenance and hassle-free - it tries to include
70 more files than necessary to make sure everything works out of the
71 box. The extra files (such as the unicode database) can take
72 substantial amounts of memory and file size.
73
74 With staticperl, the burden is mostly with the developer - only
75 direct compile-time dependencies and AutoLoader are handled
76 automatically. This means the modules to include often need to be
77 tweaked manually.
78
79 * PAR works out of the box, staticperl does not.
80
81 Maintaining your own custom perl build can be a pain in the ass, and
82 while staticperl tries to make this easy, it still requires a custom
83 perl build and possibly fiddling with some modules. PAR is likely to
84 produce results faster.
85
86 Ok, PAR never has worked for me out of the box, and for some people,
87 staticperl does work out of the box, as they don't count "fiddling
88 with module use lists" against it, but nevertheless, staticperl is
89 certainly a bit more difficult to use.
90
91 HOW DOES IT WORK?
92 Simple: staticperl downloads, compile and installs a perl version of
93 your choice in ~/.staticperl. You can add extra modules either by
94 letting staticperl install them for you automatically, or by using CPAN
95 and doing it interactively. This usually takes 5-10 minutes, depending
96 on the speed of your computer and your internet connection.
97
98 It is possible to do program development at this stage, too.
99
100 Afterwards, you create a list of files and modules you want to include,
101 and then either build a new perl binary (that acts just like a normal
102 perl except everything is compiled in), or you create bundle files
103 (basically C sources you can use to embed all files into your project).
104
105 This step is very fast (a few seconds if PPI is not used for stripping,
106 more seconds otherwise, as PPI is very slow), and can be tweaked and
107 repeated as often as necessary.
108
109 THE STATICPERL SCRIPT
110 This module installs a script called staticperl into your perl binary
111 directory. The script is fully self-contained, and can be used without
112 perl (for example, in an uClibc chroot environment). In fact, it can be
113 extracted from the "App::Staticperl" distribution tarball as
114 bin/staticperl, without any installation.
115
116 staticperl interprets the first argument as a command to execute,
117 optionally followed by any parameters.
118
119 There are two command categories: the "phase 1" commands which deal with
120 installing perl and perl modules, and the "phase 2" commands, which deal
121 with creating binaries and bundle files.
122
123 PHASE 1 COMMANDS: INSTALLING PERL
124 The most important command is install, which does basically everything.
125 The default is to download and install perl 5.12.2 and a few modules
126 required by staticperl itself, but all this can (and should) be changed
127 - see CONFIGURATION, below.
128
129 The command
130
131 staticperl install
132
133 Is normally all you need: It installs the perl interpreter in
134 ~/.staticperl/perl. It downloads, configures, builds and installs the
135 perl interpreter if required.
136
137 Most of the following commands simply run one or more steps of this
138 sequence.
139
140 To force recompilation or reinstallation, you need to run staticperl
141 distclean first.
142
143 staticperl fetch
144 Runs only the download and unpack phase, unless this has already
145 happened.
146
147 staticperl configure
148 Configures the unpacked perl sources, potentially after downloading
149 them first.
150
151 staticperl build
152 Builds the configured perl sources, potentially after automatically
153 configuring them.
154
155 staticperl install
156 Wipes the perl installation directory (usually ~/.staticperl/perl)
157 and installs the perl distribution, potentially after building it
158 first.
159
160 staticperl cpan [args...]
161 Starts an interactive CPAN shell that you can use to install further
162 modules. Installs the perl first if necessary, but apart from that,
163 no magic is involved: you could just as well run it manually via
164 ~/.staticperl/perl/bin/cpan.
165
166 Any additional arguments are simply passed to the cpan command.
167
168 staticperl instcpan module...
169 Tries to install all the modules given and their dependencies, using
170 CPAN.
171
172 Example:
173
174 staticperl instcpan EV AnyEvent::HTTPD Coro
175
176 staticperl instsrc directory...
177 In the unlikely case that you have unpacked perl modules around and
178 want to install from these instead of from CPAN, you can do this
179 using this command by specifying all the directories with modules in
180 them that you want to have built.
181
182 staticperl clean
183 Deletes the perl source directory (and potentially cleans up other
184 intermediate files). This can be used to clean up files only needed
185 for building perl, without removing the installed perl interpreter,
186 or to force a re-build from scratch.
187
188 At the moment, it doesn't delete downloaded tarballs.
189
190 staticperl distclean
191 This wipes your complete ~/.staticperl directory. Be careful with
192 this, it nukes your perl download, perl sources, perl distribution
193 and any installed modules. It is useful if you wish to start over
194 "from scratch" or when you want to uninstall staticperl.
195
196 PHASE 2 COMMANDS: BUILDING PERL BUNDLES
197 Building (linking) a new perl binary is handled by a separate script. To
198 make it easy to use staticperl from a chroot, the script is embedded
199 into staticperl, which will write it out and call for you with any
200 arguments you pass:
201
202 staticperl mkbundle mkbundle-args...
203
204 In the oh so unlikely case of something not working here, you can run
205 the script manually as well (by default it is written to
206 ~/.staticperl/mkbundle).
207
208 mkbundle is a more conventional command and expect the argument syntax
209 commonly used on UNIX clones. For example, this command builds a new
210 perl binary and includes Config.pm (for perl -V), AnyEvent::HTTPD, URI
211 and a custom httpd script (from eg/httpd in this distribution):
212
213 # first make sure we have perl and the required modules
214 staticperl instcpan AnyEvent::HTTPD
215
216 # now build the perl
217 staticperl mkperl -M'"Config_heavy.pl"' -MAnyEvent::Impl::Perl \
218 -MAnyEvent::HTTPD -MURI::http \
219 --add 'eg/httpd httpd.pm'
220
221 # finally, invoke it
222 ./perl -Mhttpd
223
224 As you can see, things are not quite as trivial: the Config module has a
225 hidden dependency which is not even a perl module (Config_heavy.pl),
226 AnyEvent needs at least one event loop backend that we have to specify
227 manually (here AnyEvent::Impl::Perl), and the URI module (required by
228 AnyEvent::HTTPD) implements various URI schemes as extra modules - since
229 AnyEvent::HTTPD only needs "http" URIs, we only need to include that
230 module. I found out about these dependencies by carefully watching any
231 error messages about missing modules...
232
233 Instead of building a new perl binary, you can also build a standalone
234 application:
235
236 # build the app
237 staticperl mkapp app --boot eg/httpd \
238 -MAnyEvent::Impl::Perl -MAnyEvent::HTTPD -MURI::http
239
240 # run it
241 ./app
242
243 OPTION PROCESSING
244 All options can be given as arguments on the command line (typically
245 using long (e.g. "--verbose") or short option (e.g. "-v") style). Since
246 specifying a lot of modules can make the command line very cumbersome,
247 you can put all long options into a "bundle specification file" (with or
248 without "--" prefix) and specify this bundle file instead.
249
250 For example, the command given earlier could also look like this:
251
252 staticperl mkperl httpd.bundle
253
254 And all options could be in httpd.bundle:
255
256 use "Config_heavy.pl"
257 use AnyEvent::Impl::Perl
258 use AnyEvent::HTTPD
259 use URI::http
260 add eg/httpd httpd.pm
261
262 All options that specify modules or files to be added are processed in
263 the order given on the command line (that affects the "--use" and
264 "--eval" options at the moment).
265
266 MKBUNDLE OPTIONS
267 --verbose | -v
268 Increases the verbosity level by one (the default is 1).
269
270 --quiet | -q
271 Decreases the verbosity level by one.
272
273 --strip none|pod|ppi
274 Specify the stripping method applied to reduce the file of the perl
275 sources included.
276
277 The default is "pod", which uses the Pod::Strip module to remove all
278 pod documentation, which is very fast and reduces file size a lot.
279
280 The "ppi" method uses PPI to parse and condense the perl sources.
281 This saves a lot more than just Pod::Strip, and is generally safer,
282 but is also a lot slower, so is best used for production builds.
283 Note that this method doesn't optimise for raw file size, but for
284 best compression (that means that the uncompressed file size is a
285 bit larger, but the files compress better, e.g. with upx).
286
287 Last not least, if you need accurate line numbers in error messages,
288 or in the unlikely case where "pod" is too slow, or some module gets
289 mistreated, you can specify "none" to not mangle included perl
290 sources in any way.
291
292 --perl
293 After writing out the bundle files, try to link a new perl
294 interpreter. It will be called perl and will be left in the current
295 working directory. The bundle files will be removed.
296
297 This switch is automatically used when staticperl is invoked with
298 the "mkperl" command (instead of "mkbundle"):
299
300 # build a new ./perl with only common::sense in it - very small :)
301 staticperl mkperl -Mcommon::sense
302
303 --app name
304 After writing out the bundle files, try to link a new standalone
305 program. It will be called "name", and the bundle files get removed
306 after linking it.
307
308 The difference to the (mutually exclusive) "--perl" option is that
309 the binary created by this option will not try to act as a perl
310 interpreter - instead it will simply initialise the perl
311 interpreter, clean it up and exit.
312
313 This switch is automatically used when staticperl is invoked with
314 the "mkapp" command (instead of "mkbundle"):
315
316 To let it do something useful you *must* add some boot code, e.g.
317 with the "--boot" option.
318
319 Example: create a standalone perl binary that will execute appfile
320 when it is started.
321
322 staticperl mkbundle --app myexe --boot appfile
323
324 --use module | -Mmodule
325 Include the named module and all direct dependencies. This is done
326 by "require"'ing the module in a subprocess and tracing which other
327 modules and files it actually loads. If the module uses AutoLoader,
328 then all splitfiles will be included as well.
329
330 Example: include AnyEvent and AnyEvent::Impl::Perl.
331
332 staticperl mkbundle --use AnyEvent --use AnyEvent::Impl::Perl
333
334 Sometimes you want to load old-style "perl libraries" (.pl files),
335 or maybe other weirdly named files. To do that, you need to quote
336 the name in single or double quotes. When given on the command line,
337 you probably need to quote once more to avoid your shell
338 interpreting it. Common cases that need this are Config_heavy.pl and
339 utf8_heavy.pl.
340
341 Example: include the required files for perl -V to work in all its
342 glory (Config.pm is included automatically by this).
343
344 # bourne shell
345 staticperl mkbundle --use '"Config_heavy.pl"'
346
347 # bundle specification file
348 use "Config_heavy.pl"
349
350 The "-Mmodule" syntax is included as an alias that might be easier
351 to remember than "use". Or maybe it confuses people. Time will tell.
352 Or maybe not. Argh.
353
354 --eval "perl code" | -e "perl code"
355 Sometimes it is easier (or necessary) to specify dependencies using
356 perl code, or maybe one of the modules you use need a special use
357 statement. In that case, you can use "eval" to execute some perl
358 snippet or set some variables or whatever you need. All files
359 "require"'d or "use"'d in the script are included in the final
360 bundle.
361
362 Keep in mind that mkbundle will only "require" the modules named by
363 the "--use" option, so do not expect the symbols from modules you
364 "--use"'d earlier on the command line to be available.
365
366 Example: force AnyEvent to detect a backend and therefore include it
367 in the final bundle.
368
369 staticperl mkbundle --eval 'use AnyEvent; AnyEvent::detect'
370
371 # or like this
372 staticperl mkbundle -MAnyEvent --eval 'use AnyEvent; AnyEvent::detect'
373
374 Example: use a separate "bootstrap" script that "use"'s lots of
375 modules and include this in the final bundle, to be executed
376 automatically.
377
378 staticperl mkbundle --eval 'do "bootstrap"' --boot bootstrap
379
380 --boot filename
381 Include the given file in the bundle and arrange for it to be
382 executed (using a "require") before anything else when the new perl
383 is initialised. This can be used to modify @INC or anything else
384 before the perl interpreter executes scripts given on the command
385 line (or via "-e"). This works even in an embedded interpreter.
386
387 --add "file" | --add "file alias"
388 Adds the given (perl) file into the bundle (and optionally call it
389 "alias"). This is useful to include any custom files into the
390 bundle.
391
392 Example: embed the file httpd as httpd.pm when creating the bundle.
393
394 staticperl mkperl --add "httpd httpd.pm"
395
396 It is also a great way to add any custom modules:
397
398 # specification file
399 add file1 myfiles/file1
400 add file2 myfiles/file2
401 add file3 myfiles/file3
402
403 --binadd "file" | --add "file alias"
404 Just like "--add", except that it treats the file as binary and adds
405 it without any processing.
406
407 You should probably add a "/" prefix to avoid clashing with embedded
408 perl files (whose paths do not start with "/"), and/or use a special
409 directory, such as "/res/name".
410
411 You can later get a copy of these files by calling "staticperl::find
412 "alias"".
413
414 --static
415 When "--perl" is also given, link statically instead of dynamically.
416 The default is to link the new perl interpreter fully dynamic (that
417 means all perl modules are linked statically, but all external
418 libraries are still referenced dynamically).
419
420 Keep in mind that Solaris doesn't support static linking at all, and
421 systems based on GNU libc don't really support it in a usable
422 fashion either. Try uClibc if you want to create fully statically
423 linked executables, or try the "--staticlibs" option to link only
424 some libraries statically.
425
426 any other argument
427 Any other argument is interpreted as a bundle specification file,
428 which supports most long options (without extra quoting), one option
429 per line.
430
431 STATCPERL CONFIGURATION AND HOOKS
432 During (each) startup, staticperl tries to source the following shell
433 files in order:
434
435 /etc/staticperlrc
436 ~/.staticperlrc
437 $STATICPERL/rc
438
439 They can be used to override shell variables, or define functions to be
440 called at specific phases.
441
442 Note that the last file is erased during staticperl distclean, so
443 generally should not be used.
444
445 CONFIGURATION VARIABLES
446 Variables you *should* override
447 "EMAIL"
448 The e-mail address of the person who built this binary. Has no good
449 default, so should be specified by you.
450
451 "CPAN"
452 The URL of the CPAN mirror to use (e.g.
453 <http://mirror.netcologne.de/cpan/>).
454
455 "EXTRA_MODULES"
456 Additional modules installed during staticperl install. Here you can
457 set which modules you want have to installed from CPAN.
458
459 Example: I really really need EV, AnyEvent, Coro and AnyEvent::AIO.
460
461 EXTRA_MODULES="EV AnyEvent Coro AnyEvent::AIO"
462
463 Note that you can also use a "postinstall" hook to achieve this, and
464 more.
465
466 Variables you might *want* to override
467 "STATICPERL"
468 The directory where staticperl stores all its files (default:
469 ~/.staticperl).
470
471 "PERL_MM_USE_DEFAULT", "EV_EXTRA_DEFS", ...
472 Usually set to 1 to make modules "less inquisitive" during their
473 installation, you can set any environment variable you want - some
474 modules (such as Coro or EV) use environment variables for further
475 tweaking.
476
477 "PERL_VERSION"
478 The perl version to install - default is currently 5.12.2, but 5.8.9
479 is also a good choice (5.8.9 is much smaller than 5.12.2, while
480 5.10.1 is about as big as 5.12.2).
481
482 "PERL_PREFIX"
483 The prefix where perl gets installed (default: $STATICPERL/perl),
484 i.e. where the bin and lib subdirectories will end up.
485
486 "PERL_CONFIGURE"
487 Additional Configure options - these are simply passed to the perl
488 Configure script. For example, if you wanted to enable dynamic
489 loading, you could pass "-Dusedl". To enable ithreads (Why would you
490 want that insanity? Don't! Use forks instead!) you would pass
491 "-Duseithreads" and so on.
492
493 More commonly, you would either activate 64 bit integer support
494 ("-Duse64bitint"), or disable large files support (-Uuselargefiles),
495 to reduce filesize further.
496
497 "PERL_CPPFLAGS", "PERL_OPTIMIZE", "PERL_LDFLAGS", "PERL_LIBS"
498 These flags are passed to perl's Configure script, and are generally
499 optimised for small size (at the cost of performance). Since they
500 also contain subtle workarounds around various build issues,
501 changing these usually requires understanding their default values -
502 best look at the top of the staticperl script for more info on
503 these.
504
505 Variables you probably *do not want* to override
506 "MKBUNDLE"
507 Where staticperl writes the "mkbundle" command to (default:
508 $STATICPERL/mkbundle).
509
510 "STATICPERL_MODULES"
511 Additional modules needed by "mkbundle" - should therefore not be
512 changed unless you know what you are doing.
513
514 OVERRIDABLE HOOKS
515 In addition to environment variables, it is possible to provide some
516 shell functions that are called at specific times. To provide your own
517 commands, just define the corresponding function.
518
519 Example: install extra modules from CPAN and from some directories at
520 staticperl install time.
521
522 postinstall() {
523 rm -rf lib/threads* # weg mit Schaden
524 instcpan IO::AIO EV
525 instsrc ~/src/AnyEvent
526 instsrc ~/src/XML-Sablotron-1.0100001
527 instcpan Anyevent::AIO AnyEvent::HTTPD
528 }
529
530 preconfigure
531 Called just before running ./Configur in the perl source directory.
532 Current working directory is the perl source directory.
533
534 This can be used to set any "PERL_xxx" variables, which might be
535 costly to compute.
536
537 postconfigure
538 Called after configuring, but before building perl. Current working
539 directory is the perl source directory.
540
541 Could be used to tailor/patch config.sh (followed by sh Configure
542 -S) or do any other modifications.
543
544 postbuild
545 Called after building, but before installing perl. Current working
546 directory is the perl source directory.
547
548 I have no clue what this could be used for - tell me.
549
550 postinstall
551 Called after perl and any extra modules have been installed in
552 $PREFIX, but before setting the "installation O.K." flag.
553
554 The current working directory is $PREFIX, but maybe you should not
555 rely on that.
556
557 This hook is most useful to customise the installation, by deleting
558 files, or installing extra modules using the "instcpan" or "instsrc"
559 functions.
560
561 The script must return with a zero exit status, or the installation
562 will fail.
563
564 ANATOMY OF A BUNDLE
565 When not building a new perl binary, "mkbundle" will leave a number of
566 files in the current working directory, which can be used to embed a
567 perl interpreter in your program.
568
569 Intimate knowledge of perlembed and preferably some experience with
570 embedding perl is highly recommended.
571
572 "mkperl" (or the "--perl" option) basically does this to link the new
573 interpreter (it also adds a main program to bundle.):
574
575 $Config{cc} $(cat bundle.ccopts) -o perl bundle.c $(cat bundle.ldopts)
576
577 bundle.h
578 A header file that contains the prototypes of the few symbols
579 "exported" by bundle.c, and also exposes the perl headers to the
580 application.
581
582 staticperl_init ()
583 Initialises the perl interpreter. You can use the normal perl
584 functions after calling this function, for example, to define
585 extra functions or to load a .pm file that contains some
586 initialisation code, or the main program function:
587
588 XS (xsfunction)
589 {
590 dXSARGS;
591
592 // now we have items, ST(i) etc.
593 }
594
595 static void
596 run_myapp(void)
597 {
598 staticperl_init ();
599 newXSproto ("myapp::xsfunction", xsfunction, __FILE__, "$$;$");
600 eval_pv ("require myapp::main", 1); // executes "myapp/main.pm"
601 }
602
603 staticperl_xs_init (pTHX)
604 Sometimes you need direct control over "perl_parse" and
605 "perl_run", in which case you do not want to use
606 "staticperl_init" but call them on your own.
607
608 Then you need this function - either pass it directly as the
609 "xs_init" function to "perl_parse", or call it from your own
610 "xs_init" function.
611
612 staticperl_cleanup ()
613 In the unlikely case that you want to destroy the perl
614 interpreter, here is the corresponding function.
615
616 PerlInterpreter *staticperl
617 The perl interpreter pointer used by staticperl. Not normally so
618 useful, but there it is.
619
620 bundle.ccopts
621 Contains the compiler options required to compile at least bundle.c
622 and any file that includes bundle.h - you should probably use it in
623 your "CFLAGS".
624
625 bundle.ldopts
626 The linker options needed to link the final program.
627
628 RUNTIME FUNCTIONALITY
629 Binaries created with "mkbundle"/"mkperl" contain extra functions, which
630 are required to access the bundled perl sources, but might be useful for
631 other purposes.
632
633 In addition, for the embedded loading of perl files to work, staticperl
634 overrides the @INC array.
635
636 $file = staticperl::find $path
637 Returns the data associated with the given $path (e.g.
638 "Digest/MD5.pm", "auto/POSIX/autosplit.ix"), which is basically the
639 UNIX path relative to the perl library directory.
640
641 Returns "undef" if the file isn't embedded.
642
643 @paths = staticperl::list
644 Returns the list of all paths embedded in this binary.
645
646 FULLY STATIC BINARIES - BUILDROOT
647 To make truly static (Linux-) libraries, you might want to have a look
648 at buildroot (<http://buildroot.uclibc.org/>).
649
650 Buildroot is primarily meant to set up a cross-compile environment
651 (which is not so useful as perl doesn't quite like cross compiles), but
652 it can also compile a chroot environment where you can use staticperl.
653
654 To do so, download buildroot, and enable "Build options => development
655 files in target filesystem" and optionally "Build options => gcc
656 optimization level (optimize for size)". At the time of writing, I had
657 good experiences with GCC 4.4.x but not GCC 4.5.
658
659 To minimise code size, I used "-pipe -ffunction-sections -fdata-sections
660 -finline-limit=8 -fno-builtin-strlen -mtune=i386". The "-mtune=i386"
661 doesn't decrease codesize much, but it makes the file much more
662 compressible.
663
664 If you don't need Coro or threads, you can go with "linuxthreads.old"
665 (or no thread support). For Coro, it is highly recommended to switch to
666 a uClibc newer than 0.9.31 (at the time of this writing, I used the
667 20101201 snapshot) and enable NPTL, otherwise Coro needs to be
668 configured with the ultra-slow pthreads backend to work around
669 linuxthreads bugs (it also uses twice the address space needed for
670 stacks).
671
672 If you use "linuxthreads.old", then you should also be aware that uClibc
673 shares "errno" between all threads when statically linking. See
674 <http://lists.uclibc.org/pipermail/uclibc/2010-June/044157.html> for a
675 workaround (And <https://bugs.uclibc.org/2089> for discussion).
676
677 "ccache" support is also recommended, especially if you want to play
678 around with buildroot options. Enabling the "miniperl" package will
679 probably enable all options required for a successful perl build.
680 staticperl itself additionally needs either "wget" (recommended, for
681 CPAN) or "curl".
682
683 As for shells, busybox should provide all that is needed, but the
684 default busybox configuration doesn't include comm which is needed by
685 perl - either make a custom busybox config, or compile coreutils.
686
687 For the latter route, you might find that bash has some bugs that keep
688 it from working properly in a chroot - either use dash (and link it to
689 /bin/sh inside the chroot) or link busybox to /bin/sh, using it's
690 built-in ash shell.
691
692 Finally, you need /dev/null inside the chroot for many scripts to work -
693 cp /dev/null output/target/dev or bind-mounting your /dev will both
694 provide this.
695
696 After you have compiled and set up your buildroot target, you can copy
697 staticperl from the "App::Staticperl" distribution or from your perl
698 f<bin> directory (if you installed it) into the output/target
699 filesystem, chroot inside and run it.
700
701 AUTHOR
702 Marc Lehmann <schmorp@schmorp.de>
703 http://software.schmorp.de/pkg/staticperl.html
704