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a0d0e21e |
1 | package DynaLoader; |
2 | |
8e07c86e |
3 | # And Gandalf said: 'Many folk like to know beforehand what is to |
4 | # be set on the table; but those who have laboured to prepare the |
5 | # feast like to keep their secret; for wonder makes the words of |
6 | # praise louder.' |
7 | |
8 | # (Quote from Tolkien sugested by Anno Siegel.) |
9 | # |
10 | # See pod text at end of file for documentation. |
11 | # See also ext/DynaLoader/README in source tree for other information. |
12 | # |
13 | # Tim.Bunce@ig.co.uk, August 1994 |
14 | |
73c78b0a |
15 | use vars qw($VERSION @ISA) ; |
16 | |
8e07c86e |
17 | require Carp; |
18 | require Config; |
19 | require AutoLoader; |
20 | |
21 | @ISA=qw(AutoLoader); |
22 | |
73c78b0a |
23 | $VERSION = "1.00" ; |
8e07c86e |
24 | |
25 | sub import { } # override import inherited from AutoLoader |
26 | |
27 | # enable debug/trace messages from DynaLoader perl code |
28 | $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug; |
29 | |
d404d5bf |
30 | ($dl_dlext, $dlsrc) |
31 | = @Config::Config{'dlext', 'dlsrc'}; |
8e07c86e |
32 | |
33 | # Some systems need special handling to expand file specifications |
34 | # (VMS support by Charles Bailey <bailey@HMIVAX.HUMGEN.UPENN.EDU>) |
35 | # See dl_expandspec() for more details. Should be harmless but |
36 | # inefficient to define on systems that don't need it. |
d404d5bf |
37 | $do_expand = $Is_VMS = $^O eq 'VMS'; |
8e07c86e |
38 | |
39 | @dl_require_symbols = (); # names of symbols we need |
40 | @dl_resolve_using = (); # names of files to link with |
41 | @dl_library_path = (); # path to look for files |
42 | |
43 | # This is a fix to support DLD's unfortunate desire to relink -lc |
44 | @dl_resolve_using = dl_findfile('-lc') if $dlsrc eq "dl_dld.xs"; |
45 | |
46 | # Initialise @dl_library_path with the 'standard' library path |
47 | # for this platform as determined by Configure |
48 | push(@dl_library_path, split(' ',$Config::Config{'libpth'})); |
49 | |
50 | # Add to @dl_library_path any extra directories we can gather from |
51 | # environment variables. So far LD_LIBRARY_PATH is the only known |
52 | # variable used for this purpose. Others may be added later. |
53 | push(@dl_library_path, split(/:/, $ENV{LD_LIBRARY_PATH})) |
54 | if $ENV{LD_LIBRARY_PATH}; |
55 | |
56 | |
57 | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here. |
54d6a3b3 |
58 | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader); |
8e07c86e |
59 | |
60 | |
61 | if ($dl_debug) { |
62 | print STDERR "DynaLoader.pm loaded (@INC, @dl_library_path)\n"; |
63 | print STDERR "DynaLoader not linked into this perl\n" |
64 | unless defined(&boot_DynaLoader); |
65 | } |
66 | |
67 | 1; # End of main code |
68 | |
69 | |
70 | # The bootstrap function cannot be autoloaded (without complications) |
71 | # so we define it here: |
72 | |
73 | sub bootstrap { |
74 | # use local vars to enable $module.bs script to edit values |
75 | local(@args) = @_; |
76 | local($module) = $args[0]; |
77 | local(@dirs, $file); |
78 | |
4633a7c4 |
79 | Carp::confess("Usage: DynaLoader::bootstrap(module)") unless $module; |
8e07c86e |
80 | |
81 | # A common error on platforms which don't support dynamic loading. |
82 | # Since it's fatal and potentially confusing we give a detailed message. |
83 | Carp::croak("Can't load module $module, dynamic loading not available in this perl.\n". |
84 | " (You may need to build a new perl executable which either supports\n". |
85 | " dynamic loading or has the $module module statically linked into it.)\n") |
86 | unless defined(&dl_load_file); |
87 | |
88 | my @modparts = split(/::/,$module); |
89 | my $modfname = $modparts[-1]; |
90 | |
91 | # Some systems have restrictions on files names for DLL's etc. |
92 | # mod2fname returns appropriate file base name (typically truncated) |
93 | # It may also edit @modparts if required. |
94 | $modfname = &mod2fname(\@modparts) if defined &mod2fname; |
95 | |
96 | my $modpname = join('/',@modparts); |
97 | |
98 | print STDERR "DynaLoader::bootstrap for $module ", |
99 | "(auto/$modpname/$modfname.$dl_dlext)\n" if $dl_debug; |
100 | |
101 | foreach (@INC) { |
54d6a3b3 |
102 | chop($_ = VMS::Filespec::unixpath($_)) if $Is_VMS; |
8e07c86e |
103 | my $dir = "$_/auto/$modpname"; |
104 | next unless -d $dir; # skip over uninteresting directories |
105 | |
106 | # check for common cases to avoid autoload of dl_findfile |
107 | last if ($file=_check_file("$dir/$modfname.$dl_dlext")); |
108 | |
109 | # no luck here, save dir for possible later dl_findfile search |
110 | push(@dirs, "-L$dir"); |
111 | } |
112 | # last resort, let dl_findfile have a go in all known locations |
113 | $file = dl_findfile(@dirs, map("-L$_",@INC), $modfname) unless $file; |
114 | |
4633a7c4 |
115 | Carp::croak("Can't find loadable object for module $module in \@INC (@INC)") |
8e07c86e |
116 | unless $file; |
117 | |
118 | my $bootname = "boot_$module"; |
119 | $bootname =~ s/\W/_/g; |
120 | @dl_require_symbols = ($bootname); |
121 | |
122 | # Execute optional '.bootstrap' perl script for this module. |
123 | # The .bs file can be used to configure @dl_resolve_using etc to |
124 | # match the needs of the individual module on this architecture. |
125 | my $bs = $file; |
126 | $bs =~ s/(\.\w+)?$/\.bs/; # look for .bs 'beside' the library |
127 | if (-s $bs) { # only read file if it's not empty |
d404d5bf |
128 | print STDERR "BS: $bs ($^O, $dlsrc)\n" if $dl_debug; |
8e07c86e |
129 | eval { do $bs; }; |
130 | warn "$bs: $@\n" if $@; |
131 | } |
132 | |
133 | # Many dynamic extension loading problems will appear to come from |
134 | # this section of code: XYZ failed at line 123 of DynaLoader.pm. |
135 | # Often these errors are actually occurring in the initialisation |
136 | # C code of the extension XS file. Perl reports the error as being |
137 | # in this perl code simply because this was the last perl code |
138 | # it executed. |
139 | |
140 | my $libref = dl_load_file($file) or |
4633a7c4 |
141 | Carp::croak("Can't load '$file' for module $module: ".dl_error()."\n"); |
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142 | |
143 | my @unresolved = dl_undef_symbols(); |
4633a7c4 |
144 | Carp::carp("Undefined symbols present after loading $file: @unresolved\n") |
8e07c86e |
145 | if @unresolved; |
146 | |
147 | my $boot_symbol_ref = dl_find_symbol($libref, $bootname) or |
4633a7c4 |
148 | Carp::croak("Can't find '$bootname' symbol in $file\n"); |
8e07c86e |
149 | |
150 | my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file); |
151 | |
152 | # See comment block above |
153 | &$xs(@args); |
154 | } |
155 | |
156 | |
157 | sub _check_file { # private utility to handle dl_expandspec vs -f tests |
158 | my($file) = @_; |
159 | return $file if (!$do_expand && -f $file); # the common case |
160 | return $file if ( $do_expand && ($file=dl_expandspec($file))); |
161 | return undef; |
162 | } |
163 | |
164 | |
165 | # Let autosplit and the autoloader deal with these functions: |
166 | __END__ |
167 | |
168 | |
169 | sub dl_findfile { |
170 | # Read ext/DynaLoader/DynaLoader.doc for detailed information. |
171 | # This function does not automatically consider the architecture |
172 | # or the perl library auto directories. |
173 | my (@args) = @_; |
174 | my (@dirs, $dir); # which directories to search |
175 | my (@found); # full paths to real files we have found |
d404d5bf |
176 | my $dl_ext= $Config::Config{'dlext'}; # suffix for perl extensions |
8e07c86e |
177 | my $dl_so = $Config::Config{'so'}; # suffix for shared libraries |
178 | |
179 | print STDERR "dl_findfile(@args)\n" if $dl_debug; |
180 | |
181 | # accumulate directories but process files as they appear |
182 | arg: foreach(@args) { |
183 | # Special fast case: full filepath requires no search |
54d6a3b3 |
184 | if ($Is_VMS && m%[:>/\]]% && -f $_) { |
185 | push(@found,dl_expandspec(VMS::Filespec::vmsify($_))); |
186 | last arg unless wantarray; |
187 | next; |
188 | } |
189 | elsif (m:/: && -f $_ && !$do_expand) { |
8e07c86e |
190 | push(@found,$_); |
191 | last arg unless wantarray; |
192 | next; |
193 | } |
194 | |
195 | # Deal with directories first: |
196 | # Using a -L prefix is the preferred option (faster and more robust) |
197 | if (m:^-L:) { s/^-L//; push(@dirs, $_); next; } |
198 | |
199 | # Otherwise we try to try to spot directories by a heuristic |
200 | # (this is a more complicated issue than it first appears) |
201 | if (m:/: && -d $_) { push(@dirs, $_); next; } |
202 | |
203 | # VMS: we may be using native VMS directry syntax instead of |
204 | # Unix emulation, so check this as well |
54d6a3b3 |
205 | if ($Is_VMS && /[:>\]]/ && -d $_) { push(@dirs, $_); next; } |
8e07c86e |
206 | |
207 | # Only files should get this far... |
208 | my(@names, $name); # what filenames to look for |
209 | if (m:-l: ) { # convert -lname to appropriate library name |
210 | s/-l//; |
211 | push(@names,"lib$_.$dl_so"); |
212 | push(@names,"lib$_.a"); |
213 | } else { # Umm, a bare name. Try various alternatives: |
214 | # these should be ordered with the most likely first |
d404d5bf |
215 | push(@names,"$_.$dl_ext") unless m/\.$dl_ext$/o; |
8e07c86e |
216 | push(@names,"$_.$dl_so") unless m/\.$dl_so$/o; |
217 | push(@names,"lib$_.$dl_so") unless m:/:; |
8e07c86e |
218 | push(@names,"$_.a") if !m/\.a$/ and $dlsrc eq "dl_dld.xs"; |
219 | push(@names, $_); |
220 | } |
221 | foreach $dir (@dirs, @dl_library_path) { |
222 | next unless -d $dir; |
54d6a3b3 |
223 | chop($dir = VMS::Filespec::unixpath($dir)) if $Is_VMS; |
8e07c86e |
224 | foreach $name (@names) { |
225 | my($file) = "$dir/$name"; |
226 | print STDERR " checking in $dir for $name\n" if $dl_debug; |
227 | $file = _check_file($file); |
228 | if ($file) { |
229 | push(@found, $file); |
230 | next arg; # no need to look any further |
231 | } |
232 | } |
233 | } |
234 | } |
235 | if ($dl_debug) { |
236 | foreach(@dirs) { |
237 | print STDERR " dl_findfile ignored non-existent directory: $_\n" unless -d $_; |
238 | } |
239 | print STDERR "dl_findfile found: @found\n"; |
240 | } |
241 | return $found[0] unless wantarray; |
242 | @found; |
243 | } |
244 | |
245 | |
246 | sub dl_expandspec { |
247 | my($spec) = @_; |
248 | # Optional function invoked if DynaLoader.pm sets $do_expand. |
249 | # Most systems do not require or use this function. |
250 | # Some systems may implement it in the dl_*.xs file in which case |
251 | # this autoload version will not be called but is harmless. |
252 | |
253 | # This function is designed to deal with systems which treat some |
254 | # 'filenames' in a special way. For example VMS 'Logical Names' |
255 | # (something like unix environment variables - but different). |
256 | # This function should recognise such names and expand them into |
257 | # full file paths. |
258 | # Must return undef if $spec is invalid or file does not exist. |
259 | |
260 | my $file = $spec; # default output to input |
261 | |
d404d5bf |
262 | if ($Is_VMS) { # dl_expandspec should be defined in dl_vms.xs |
4633a7c4 |
263 | Carp::croak("dl_expandspec: should be defined in XS file!\n"); |
8e07c86e |
264 | } else { |
265 | return undef unless -f $file; |
266 | } |
267 | print STDERR "dl_expandspec($spec) => $file\n" if $dl_debug; |
268 | $file; |
269 | } |
270 | |
271 | |
3b35bae3 |
272 | =head1 NAME |
273 | |
274 | DynaLoader - Dynamically load C libraries into Perl code |
275 | |
276 | dl_error(), dl_findfile(), dl_expandspec(), dl_load_file(), dl_find_symbol(), dl_undef_symbols(), dl_install_xsub(), boostrap() - routines used by DynaLoader modules |
277 | |
278 | =head1 SYNOPSIS |
279 | |
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280 | package YourPackage; |
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281 | require DynaLoader; |
c2960299 |
282 | @ISA = qw(... DynaLoader ...); |
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283 | bootstrap YourPackage; |
3b35bae3 |
284 | |
285 | |
286 | =head1 DESCRIPTION |
287 | |
c2960299 |
288 | This document defines a standard generic interface to the dynamic |
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289 | linking mechanisms available on many platforms. Its primary purpose is |
290 | to implement automatic dynamic loading of Perl modules. |
291 | |
c2960299 |
292 | This document serves as both a specification for anyone wishing to |
293 | implement the DynaLoader for a new platform and as a guide for |
294 | anyone wishing to use the DynaLoader directly in an application. |
295 | |
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296 | The DynaLoader is designed to be a very simple high-level |
297 | interface that is sufficiently general to cover the requirements |
298 | of SunOS, HP-UX, NeXT, Linux, VMS and other platforms. |
299 | |
c2960299 |
300 | It is also hoped that the interface will cover the needs of OS/2, NT |
301 | etc and also allow pseudo-dynamic linking (using C<ld -A> at runtime). |
3b35bae3 |
302 | |
303 | It must be stressed that the DynaLoader, by itself, is practically |
304 | useless for accessing non-Perl libraries because it provides almost no |
305 | Perl-to-C 'glue'. There is, for example, no mechanism for calling a C |
306 | library function or supplying arguments. It is anticipated that any |
307 | glue that may be developed in the future will be implemented in a |
308 | separate dynamically loaded module. |
309 | |
310 | DynaLoader Interface Summary |
311 | |
312 | @dl_library_path |
313 | @dl_resolve_using |
314 | @dl_require_symbols |
315 | $dl_debug |
316 | Implemented in: |
317 | bootstrap($modulename) Perl |
318 | @filepaths = dl_findfile(@names) Perl |
319 | |
320 | $libref = dl_load_file($filename) C |
321 | $symref = dl_find_symbol($libref, $symbol) C |
322 | @symbols = dl_undef_symbols() C |
323 | dl_install_xsub($name, $symref [, $filename]) C |
324 | $message = dl_error C |
325 | |
326 | =over 4 |
327 | |
328 | =item @dl_library_path |
329 | |
330 | The standard/default list of directories in which dl_findfile() will |
331 | search for libraries etc. Directories are searched in order: |
332 | $dl_library_path[0], [1], ... etc |
333 | |
334 | @dl_library_path is initialised to hold the list of 'normal' directories |
335 | (F</usr/lib>, etc) determined by B<Configure> (C<$Config{'libpth'}>). This should |
336 | ensure portability across a wide range of platforms. |
337 | |
338 | @dl_library_path should also be initialised with any other directories |
339 | that can be determined from the environment at runtime (such as |
340 | LD_LIBRARY_PATH for SunOS). |
341 | |
342 | After initialisation @dl_library_path can be manipulated by an |
343 | application using push and unshift before calling dl_findfile(). |
344 | Unshift can be used to add directories to the front of the search order |
345 | either to save search time or to override libraries with the same name |
346 | in the 'normal' directories. |
347 | |
348 | The load function that dl_load_file() calls may require an absolute |
349 | pathname. The dl_findfile() function and @dl_library_path can be |
350 | used to search for and return the absolute pathname for the |
351 | library/object that you wish to load. |
352 | |
353 | =item @dl_resolve_using |
354 | |
355 | A list of additional libraries or other shared objects which can be |
356 | used to resolve any undefined symbols that might be generated by a |
357 | later call to load_file(). |
358 | |
359 | This is only required on some platforms which do not handle dependent |
360 | libraries automatically. For example the Socket Perl extension library |
361 | (F<auto/Socket/Socket.so>) contains references to many socket functions |
362 | which need to be resolved when it's loaded. Most platforms will |
363 | automatically know where to find the 'dependent' library (e.g., |
364 | F</usr/lib/libsocket.so>). A few platforms need to to be told the location |
365 | of the dependent library explicitly. Use @dl_resolve_using for this. |
366 | |
367 | Example usage: |
368 | |
369 | @dl_resolve_using = dl_findfile('-lsocket'); |
370 | |
371 | =item @dl_require_symbols |
372 | |
373 | A list of one or more symbol names that are in the library/object file |
374 | to be dynamically loaded. This is only required on some platforms. |
375 | |
376 | =item dl_error() |
377 | |
378 | Syntax: |
379 | |
380 | $message = dl_error(); |
381 | |
382 | Error message text from the last failed DynaLoader function. Note |
383 | that, similar to errno in unix, a successful function call does not |
384 | reset this message. |
385 | |
386 | Implementations should detect the error as soon as it occurs in any of |
387 | the other functions and save the corresponding message for later |
388 | retrieval. This will avoid problems on some platforms (such as SunOS) |
389 | where the error message is very temporary (e.g., dlerror()). |
390 | |
391 | =item $dl_debug |
392 | |
393 | Internal debugging messages are enabled when $dl_debug is set true. |
394 | Currently setting $dl_debug only affects the Perl side of the |
395 | DynaLoader. These messages should help an application developer to |
396 | resolve any DynaLoader usage problems. |
397 | |
398 | $dl_debug is set to C<$ENV{'PERL_DL_DEBUG'}> if defined. |
399 | |
400 | For the DynaLoader developer/porter there is a similar debugging |
401 | variable added to the C code (see dlutils.c) and enabled if Perl was |
402 | built with the B<-DDEBUGGING> flag. This can also be set via the |
403 | PERL_DL_DEBUG environment variable. Set to 1 for minimal information or |
404 | higher for more. |
405 | |
406 | =item dl_findfile() |
407 | |
408 | Syntax: |
409 | |
410 | @filepaths = dl_findfile(@names) |
411 | |
412 | Determine the full paths (including file suffix) of one or more |
413 | loadable files given their generic names and optionally one or more |
414 | directories. Searches directories in @dl_library_path by default and |
415 | returns an empty list if no files were found. |
416 | |
417 | Names can be specified in a variety of platform independent forms. Any |
418 | names in the form B<-lname> are converted into F<libname.*>, where F<.*> is |
419 | an appropriate suffix for the platform. |
420 | |
421 | If a name does not already have a suitable prefix and/or suffix then |
422 | the corresponding file will be searched for by trying combinations of |
423 | prefix and suffix appropriate to the platform: "$name.o", "lib$name.*" |
424 | and "$name". |
425 | |
426 | If any directories are included in @names they are searched before |
c2960299 |
427 | @dl_library_path. Directories may be specified as B<-Ldir>. Any other |
428 | names are treated as filenames to be searched for. |
3b35bae3 |
429 | |
430 | Using arguments of the form C<-Ldir> and C<-lname> is recommended. |
431 | |
432 | Example: |
433 | |
434 | @dl_resolve_using = dl_findfile(qw(-L/usr/5lib -lposix)); |
435 | |
436 | |
437 | =item dl_expandspec() |
438 | |
439 | Syntax: |
440 | |
441 | $filepath = dl_expandspec($spec) |
442 | |
443 | Some unusual systems, such as VMS, require special filename handling in |
444 | order to deal with symbolic names for files (i.e., VMS's Logical Names). |
445 | |
446 | To support these systems a dl_expandspec() function can be implemented |
447 | either in the F<dl_*.xs> file or code can be added to the autoloadable |
c2960299 |
448 | dl_expandspec() function in F<DynaLoader.pm>. See F<DynaLoader.pm> for |
449 | more information. |
3b35bae3 |
450 | |
451 | =item dl_load_file() |
452 | |
453 | Syntax: |
454 | |
455 | $libref = dl_load_file($filename) |
456 | |
457 | Dynamically load $filename, which must be the path to a shared object |
458 | or library. An opaque 'library reference' is returned as a handle for |
459 | the loaded object. Returns undef on error. |
460 | |
461 | (On systems that provide a handle for the loaded object such as SunOS |
462 | and HPUX, $libref will be that handle. On other systems $libref will |
463 | typically be $filename or a pointer to a buffer containing $filename. |
464 | The application should not examine or alter $libref in any way.) |
465 | |
466 | This is function that does the real work. It should use the current |
467 | values of @dl_require_symbols and @dl_resolve_using if required. |
468 | |
469 | SunOS: dlopen($filename) |
470 | HP-UX: shl_load($filename) |
471 | Linux: dld_create_reference(@dl_require_symbols); dld_link($filename) |
472 | NeXT: rld_load($filename, @dl_resolve_using) |
473 | VMS: lib$find_image_symbol($filename,$dl_require_symbols[0]) |
474 | |
475 | |
476 | =item dl_find_symbol() |
477 | |
478 | Syntax: |
479 | |
480 | $symref = dl_find_symbol($libref, $symbol) |
481 | |
482 | Return the address of the symbol $symbol or C<undef> if not found. If the |
483 | target system has separate functions to search for symbols of different |
484 | types then dl_find_symbol() should search for function symbols first and |
485 | then other types. |
486 | |
487 | The exact manner in which the address is returned in $symref is not |
488 | currently defined. The only initial requirement is that $symref can |
489 | be passed to, and understood by, dl_install_xsub(). |
490 | |
491 | SunOS: dlsym($libref, $symbol) |
492 | HP-UX: shl_findsym($libref, $symbol) |
493 | Linux: dld_get_func($symbol) and/or dld_get_symbol($symbol) |
494 | NeXT: rld_lookup("_$symbol") |
495 | VMS: lib$find_image_symbol($libref,$symbol) |
496 | |
497 | |
498 | =item dl_undef_symbols() |
499 | |
500 | Example |
501 | |
502 | @symbols = dl_undef_symbols() |
503 | |
504 | Return a list of symbol names which remain undefined after load_file(). |
505 | Returns C<()> if not known. Don't worry if your platform does not provide |
c2960299 |
506 | a mechanism for this. Most do not need it and hence do not provide it, |
507 | they just return an empty list. |
3b35bae3 |
508 | |
509 | |
510 | =item dl_install_xsub() |
511 | |
512 | Syntax: |
513 | |
514 | dl_install_xsub($perl_name, $symref [, $filename]) |
515 | |
516 | Create a new Perl external subroutine named $perl_name using $symref as |
517 | a pointer to the function which implements the routine. This is simply |
518 | a direct call to newXSUB(). Returns a reference to the installed |
519 | function. |
520 | |
521 | The $filename parameter is used by Perl to identify the source file for |
522 | the function if required by die(), caller() or the debugger. If |
523 | $filename is not defined then "DynaLoader" will be used. |
524 | |
525 | |
526 | =item boostrap() |
527 | |
528 | Syntax: |
529 | |
530 | bootstrap($module) |
531 | |
532 | This is the normal entry point for automatic dynamic loading in Perl. |
533 | |
534 | It performs the following actions: |
535 | |
536 | =over 8 |
537 | |
538 | =item * |
539 | |
540 | locates an auto/$module directory by searching @INC |
541 | |
542 | =item * |
543 | |
544 | uses dl_findfile() to determine the filename to load |
545 | |
546 | =item * |
547 | |
548 | sets @dl_require_symbols to C<("boot_$module")> |
549 | |
550 | =item * |
551 | |
552 | executes an F<auto/$module/$module.bs> file if it exists |
553 | (typically used to add to @dl_resolve_using any files which |
554 | are required to load the module on the current platform) |
555 | |
556 | =item * |
557 | |
558 | calls dl_load_file() to load the file |
559 | |
560 | =item * |
561 | |
562 | calls dl_undef_symbols() and warns if any symbols are undefined |
563 | |
564 | =item * |
565 | |
566 | calls dl_find_symbol() for "boot_$module" |
567 | |
568 | =item * |
569 | |
570 | calls dl_install_xsub() to install it as "${module}::bootstrap" |
571 | |
572 | =item * |
573 | |
8e07c86e |
574 | calls &{"${module}::bootstrap"} to bootstrap the module (actually |
575 | it uses the function reference returned by dl_install_xsub for speed) |
3b35bae3 |
576 | |
577 | =back |
578 | |
579 | =back |
580 | |
581 | |
582 | =head1 AUTHOR |
583 | |
c2960299 |
584 | Tim Bunce, 11 August 1994. |
585 | |
3b35bae3 |
586 | This interface is based on the work and comments of (in no particular |
587 | order): Larry Wall, Robert Sanders, Dean Roehrich, Jeff Okamoto, Anno |
c2960299 |
588 | Siegel, Thomas Neumann, Paul Marquess, Charles Bailey, myself and others. |
3b35bae3 |
589 | |
590 | Larry Wall designed the elegant inherited bootstrap mechanism and |
591 | implemented the first Perl 5 dynamic loader using it. |
592 | |
3b35bae3 |
593 | =cut |