Commit | Line | Data |
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 | |
15 | require Carp; |
16 | require Config; |
17 | require AutoLoader; |
18 | |
19 | @ISA=qw(AutoLoader); |
20 | |
c07a80fd |
21 | $VERSION = $VERSION = "1.00" ; |
8e07c86e |
22 | |
23 | sub import { } # override import inherited from AutoLoader |
24 | |
25 | # enable debug/trace messages from DynaLoader perl code |
26 | $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug; |
27 | |
28 | ($dl_dlext, $dlsrc, $osname) |
29 | = @Config::Config{'dlext', 'dlsrc', 'osname'}; |
30 | |
31 | # Some systems need special handling to expand file specifications |
32 | # (VMS support by Charles Bailey <bailey@HMIVAX.HUMGEN.UPENN.EDU>) |
33 | # See dl_expandspec() for more details. Should be harmless but |
34 | # inefficient to define on systems that don't need it. |
54d6a3b3 |
35 | $do_expand = $Is_VMS = $osname eq 'VMS'; |
8e07c86e |
36 | |
37 | @dl_require_symbols = (); # names of symbols we need |
38 | @dl_resolve_using = (); # names of files to link with |
39 | @dl_library_path = (); # path to look for files |
40 | |
41 | # This is a fix to support DLD's unfortunate desire to relink -lc |
42 | @dl_resolve_using = dl_findfile('-lc') if $dlsrc eq "dl_dld.xs"; |
43 | |
44 | # Initialise @dl_library_path with the 'standard' library path |
45 | # for this platform as determined by Configure |
46 | push(@dl_library_path, split(' ',$Config::Config{'libpth'})); |
47 | |
48 | # Add to @dl_library_path any extra directories we can gather from |
49 | # environment variables. So far LD_LIBRARY_PATH is the only known |
50 | # variable used for this purpose. Others may be added later. |
51 | push(@dl_library_path, split(/:/, $ENV{LD_LIBRARY_PATH})) |
52 | if $ENV{LD_LIBRARY_PATH}; |
53 | |
54 | |
55 | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here. |
54d6a3b3 |
56 | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader); |
8e07c86e |
57 | |
58 | |
59 | if ($dl_debug) { |
60 | print STDERR "DynaLoader.pm loaded (@INC, @dl_library_path)\n"; |
61 | print STDERR "DynaLoader not linked into this perl\n" |
62 | unless defined(&boot_DynaLoader); |
63 | } |
64 | |
65 | 1; # End of main code |
66 | |
67 | |
68 | # The bootstrap function cannot be autoloaded (without complications) |
69 | # so we define it here: |
70 | |
71 | sub bootstrap { |
72 | # use local vars to enable $module.bs script to edit values |
73 | local(@args) = @_; |
74 | local($module) = $args[0]; |
75 | local(@dirs, $file); |
76 | |
4633a7c4 |
77 | Carp::confess("Usage: DynaLoader::bootstrap(module)") unless $module; |
8e07c86e |
78 | |
79 | # A common error on platforms which don't support dynamic loading. |
80 | # Since it's fatal and potentially confusing we give a detailed message. |
81 | Carp::croak("Can't load module $module, dynamic loading not available in this perl.\n". |
82 | " (You may need to build a new perl executable which either supports\n". |
83 | " dynamic loading or has the $module module statically linked into it.)\n") |
84 | unless defined(&dl_load_file); |
85 | |
86 | my @modparts = split(/::/,$module); |
87 | my $modfname = $modparts[-1]; |
88 | |
89 | # Some systems have restrictions on files names for DLL's etc. |
90 | # mod2fname returns appropriate file base name (typically truncated) |
91 | # It may also edit @modparts if required. |
92 | $modfname = &mod2fname(\@modparts) if defined &mod2fname; |
93 | |
94 | my $modpname = join('/',@modparts); |
95 | |
96 | print STDERR "DynaLoader::bootstrap for $module ", |
97 | "(auto/$modpname/$modfname.$dl_dlext)\n" if $dl_debug; |
98 | |
99 | foreach (@INC) { |
54d6a3b3 |
100 | chop($_ = VMS::Filespec::unixpath($_)) if $Is_VMS; |
8e07c86e |
101 | my $dir = "$_/auto/$modpname"; |
102 | next unless -d $dir; # skip over uninteresting directories |
103 | |
104 | # check for common cases to avoid autoload of dl_findfile |
105 | last if ($file=_check_file("$dir/$modfname.$dl_dlext")); |
106 | |
107 | # no luck here, save dir for possible later dl_findfile search |
108 | push(@dirs, "-L$dir"); |
109 | } |
110 | # last resort, let dl_findfile have a go in all known locations |
111 | $file = dl_findfile(@dirs, map("-L$_",@INC), $modfname) unless $file; |
112 | |
4633a7c4 |
113 | Carp::croak("Can't find loadable object for module $module in \@INC (@INC)") |
8e07c86e |
114 | unless $file; |
115 | |
116 | my $bootname = "boot_$module"; |
117 | $bootname =~ s/\W/_/g; |
118 | @dl_require_symbols = ($bootname); |
119 | |
120 | # Execute optional '.bootstrap' perl script for this module. |
121 | # The .bs file can be used to configure @dl_resolve_using etc to |
122 | # match the needs of the individual module on this architecture. |
123 | my $bs = $file; |
124 | $bs =~ s/(\.\w+)?$/\.bs/; # look for .bs 'beside' the library |
125 | if (-s $bs) { # only read file if it's not empty |
126 | print STDERR "BS: $bs ($osname, $dlsrc)\n" if $dl_debug; |
127 | eval { do $bs; }; |
128 | warn "$bs: $@\n" if $@; |
129 | } |
130 | |
131 | # Many dynamic extension loading problems will appear to come from |
132 | # this section of code: XYZ failed at line 123 of DynaLoader.pm. |
133 | # Often these errors are actually occurring in the initialisation |
134 | # C code of the extension XS file. Perl reports the error as being |
135 | # in this perl code simply because this was the last perl code |
136 | # it executed. |
137 | |
138 | my $libref = dl_load_file($file) or |
4633a7c4 |
139 | Carp::croak("Can't load '$file' for module $module: ".dl_error()."\n"); |
8e07c86e |
140 | |
141 | my @unresolved = dl_undef_symbols(); |
4633a7c4 |
142 | Carp::carp("Undefined symbols present after loading $file: @unresolved\n") |
8e07c86e |
143 | if @unresolved; |
144 | |
145 | my $boot_symbol_ref = dl_find_symbol($libref, $bootname) or |
4633a7c4 |
146 | Carp::croak("Can't find '$bootname' symbol in $file\n"); |
8e07c86e |
147 | |
148 | my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file); |
149 | |
150 | # See comment block above |
151 | &$xs(@args); |
152 | } |
153 | |
154 | |
155 | sub _check_file { # private utility to handle dl_expandspec vs -f tests |
156 | my($file) = @_; |
157 | return $file if (!$do_expand && -f $file); # the common case |
158 | return $file if ( $do_expand && ($file=dl_expandspec($file))); |
159 | return undef; |
160 | } |
161 | |
162 | |
163 | # Let autosplit and the autoloader deal with these functions: |
164 | __END__ |
165 | |
166 | |
167 | sub dl_findfile { |
168 | # Read ext/DynaLoader/DynaLoader.doc for detailed information. |
169 | # This function does not automatically consider the architecture |
170 | # or the perl library auto directories. |
171 | my (@args) = @_; |
172 | my (@dirs, $dir); # which directories to search |
173 | my (@found); # full paths to real files we have found |
8e07c86e |
174 | my $dl_so = $Config::Config{'so'}; # suffix for shared libraries |
175 | |
176 | print STDERR "dl_findfile(@args)\n" if $dl_debug; |
177 | |
178 | # accumulate directories but process files as they appear |
179 | arg: foreach(@args) { |
180 | # Special fast case: full filepath requires no search |
54d6a3b3 |
181 | if ($Is_VMS && m%[:>/\]]% && -f $_) { |
182 | push(@found,dl_expandspec(VMS::Filespec::vmsify($_))); |
183 | last arg unless wantarray; |
184 | next; |
185 | } |
186 | elsif (m:/: && -f $_ && !$do_expand) { |
8e07c86e |
187 | push(@found,$_); |
188 | last arg unless wantarray; |
189 | next; |
190 | } |
191 | |
192 | # Deal with directories first: |
193 | # Using a -L prefix is the preferred option (faster and more robust) |
194 | if (m:^-L:) { s/^-L//; push(@dirs, $_); next; } |
195 | |
196 | # Otherwise we try to try to spot directories by a heuristic |
197 | # (this is a more complicated issue than it first appears) |
198 | if (m:/: && -d $_) { push(@dirs, $_); next; } |
199 | |
200 | # VMS: we may be using native VMS directry syntax instead of |
201 | # Unix emulation, so check this as well |
54d6a3b3 |
202 | if ($Is_VMS && /[:>\]]/ && -d $_) { push(@dirs, $_); next; } |
8e07c86e |
203 | |
204 | # Only files should get this far... |
205 | my(@names, $name); # what filenames to look for |
206 | if (m:-l: ) { # convert -lname to appropriate library name |
207 | s/-l//; |
208 | push(@names,"lib$_.$dl_so"); |
209 | push(@names,"lib$_.a"); |
210 | } else { # Umm, a bare name. Try various alternatives: |
211 | # these should be ordered with the most likely first |
212 | push(@names,"$_.$dl_so") unless m/\.$dl_so$/o; |
213 | push(@names,"lib$_.$dl_so") unless m:/:; |
214 | push(@names,"$_.o") unless m/\.(o|$dl_so)$/o; |
215 | push(@names,"$_.a") if !m/\.a$/ and $dlsrc eq "dl_dld.xs"; |
216 | push(@names, $_); |
217 | } |
218 | foreach $dir (@dirs, @dl_library_path) { |
219 | next unless -d $dir; |
54d6a3b3 |
220 | chop($dir = VMS::Filespec::unixpath($dir)) if $Is_VMS; |
8e07c86e |
221 | foreach $name (@names) { |
222 | my($file) = "$dir/$name"; |
223 | print STDERR " checking in $dir for $name\n" if $dl_debug; |
224 | $file = _check_file($file); |
225 | if ($file) { |
226 | push(@found, $file); |
227 | next arg; # no need to look any further |
228 | } |
229 | } |
230 | } |
231 | } |
232 | if ($dl_debug) { |
233 | foreach(@dirs) { |
234 | print STDERR " dl_findfile ignored non-existent directory: $_\n" unless -d $_; |
235 | } |
236 | print STDERR "dl_findfile found: @found\n"; |
237 | } |
238 | return $found[0] unless wantarray; |
239 | @found; |
240 | } |
241 | |
242 | |
243 | sub dl_expandspec { |
244 | my($spec) = @_; |
245 | # Optional function invoked if DynaLoader.pm sets $do_expand. |
246 | # Most systems do not require or use this function. |
247 | # Some systems may implement it in the dl_*.xs file in which case |
248 | # this autoload version will not be called but is harmless. |
249 | |
250 | # This function is designed to deal with systems which treat some |
251 | # 'filenames' in a special way. For example VMS 'Logical Names' |
252 | # (something like unix environment variables - but different). |
253 | # This function should recognise such names and expand them into |
254 | # full file paths. |
255 | # Must return undef if $spec is invalid or file does not exist. |
256 | |
257 | my $file = $spec; # default output to input |
258 | |
259 | if ($osname eq 'VMS') { # dl_expandspec should be defined in dl_vms.xs |
4633a7c4 |
260 | Carp::croak("dl_expandspec: should be defined in XS file!\n"); |
8e07c86e |
261 | } else { |
262 | return undef unless -f $file; |
263 | } |
264 | print STDERR "dl_expandspec($spec) => $file\n" if $dl_debug; |
265 | $file; |
266 | } |
267 | |
268 | |
3b35bae3 |
269 | =head1 NAME |
270 | |
271 | DynaLoader - Dynamically load C libraries into Perl code |
272 | |
273 | dl_error(), dl_findfile(), dl_expandspec(), dl_load_file(), dl_find_symbol(), dl_undef_symbols(), dl_install_xsub(), boostrap() - routines used by DynaLoader modules |
274 | |
275 | =head1 SYNOPSIS |
276 | |
8e07c86e |
277 | package YourPackage; |
3b35bae3 |
278 | require DynaLoader; |
c2960299 |
279 | @ISA = qw(... DynaLoader ...); |
8e07c86e |
280 | bootstrap YourPackage; |
3b35bae3 |
281 | |
282 | |
283 | =head1 DESCRIPTION |
284 | |
c2960299 |
285 | This document defines a standard generic interface to the dynamic |
3b35bae3 |
286 | linking mechanisms available on many platforms. Its primary purpose is |
287 | to implement automatic dynamic loading of Perl modules. |
288 | |
c2960299 |
289 | This document serves as both a specification for anyone wishing to |
290 | implement the DynaLoader for a new platform and as a guide for |
291 | anyone wishing to use the DynaLoader directly in an application. |
292 | |
3b35bae3 |
293 | The DynaLoader is designed to be a very simple high-level |
294 | interface that is sufficiently general to cover the requirements |
295 | of SunOS, HP-UX, NeXT, Linux, VMS and other platforms. |
296 | |
c2960299 |
297 | It is also hoped that the interface will cover the needs of OS/2, NT |
298 | etc and also allow pseudo-dynamic linking (using C<ld -A> at runtime). |
3b35bae3 |
299 | |
300 | It must be stressed that the DynaLoader, by itself, is practically |
301 | useless for accessing non-Perl libraries because it provides almost no |
302 | Perl-to-C 'glue'. There is, for example, no mechanism for calling a C |
303 | library function or supplying arguments. It is anticipated that any |
304 | glue that may be developed in the future will be implemented in a |
305 | separate dynamically loaded module. |
306 | |
307 | DynaLoader Interface Summary |
308 | |
309 | @dl_library_path |
310 | @dl_resolve_using |
311 | @dl_require_symbols |
312 | $dl_debug |
313 | Implemented in: |
314 | bootstrap($modulename) Perl |
315 | @filepaths = dl_findfile(@names) Perl |
316 | |
317 | $libref = dl_load_file($filename) C |
318 | $symref = dl_find_symbol($libref, $symbol) C |
319 | @symbols = dl_undef_symbols() C |
320 | dl_install_xsub($name, $symref [, $filename]) C |
321 | $message = dl_error C |
322 | |
323 | =over 4 |
324 | |
325 | =item @dl_library_path |
326 | |
327 | The standard/default list of directories in which dl_findfile() will |
328 | search for libraries etc. Directories are searched in order: |
329 | $dl_library_path[0], [1], ... etc |
330 | |
331 | @dl_library_path is initialised to hold the list of 'normal' directories |
332 | (F</usr/lib>, etc) determined by B<Configure> (C<$Config{'libpth'}>). This should |
333 | ensure portability across a wide range of platforms. |
334 | |
335 | @dl_library_path should also be initialised with any other directories |
336 | that can be determined from the environment at runtime (such as |
337 | LD_LIBRARY_PATH for SunOS). |
338 | |
339 | After initialisation @dl_library_path can be manipulated by an |
340 | application using push and unshift before calling dl_findfile(). |
341 | Unshift can be used to add directories to the front of the search order |
342 | either to save search time or to override libraries with the same name |
343 | in the 'normal' directories. |
344 | |
345 | The load function that dl_load_file() calls may require an absolute |
346 | pathname. The dl_findfile() function and @dl_library_path can be |
347 | used to search for and return the absolute pathname for the |
348 | library/object that you wish to load. |
349 | |
350 | =item @dl_resolve_using |
351 | |
352 | A list of additional libraries or other shared objects which can be |
353 | used to resolve any undefined symbols that might be generated by a |
354 | later call to load_file(). |
355 | |
356 | This is only required on some platforms which do not handle dependent |
357 | libraries automatically. For example the Socket Perl extension library |
358 | (F<auto/Socket/Socket.so>) contains references to many socket functions |
359 | which need to be resolved when it's loaded. Most platforms will |
360 | automatically know where to find the 'dependent' library (e.g., |
361 | F</usr/lib/libsocket.so>). A few platforms need to to be told the location |
362 | of the dependent library explicitly. Use @dl_resolve_using for this. |
363 | |
364 | Example usage: |
365 | |
366 | @dl_resolve_using = dl_findfile('-lsocket'); |
367 | |
368 | =item @dl_require_symbols |
369 | |
370 | A list of one or more symbol names that are in the library/object file |
371 | to be dynamically loaded. This is only required on some platforms. |
372 | |
373 | =item dl_error() |
374 | |
375 | Syntax: |
376 | |
377 | $message = dl_error(); |
378 | |
379 | Error message text from the last failed DynaLoader function. Note |
380 | that, similar to errno in unix, a successful function call does not |
381 | reset this message. |
382 | |
383 | Implementations should detect the error as soon as it occurs in any of |
384 | the other functions and save the corresponding message for later |
385 | retrieval. This will avoid problems on some platforms (such as SunOS) |
386 | where the error message is very temporary (e.g., dlerror()). |
387 | |
388 | =item $dl_debug |
389 | |
390 | Internal debugging messages are enabled when $dl_debug is set true. |
391 | Currently setting $dl_debug only affects the Perl side of the |
392 | DynaLoader. These messages should help an application developer to |
393 | resolve any DynaLoader usage problems. |
394 | |
395 | $dl_debug is set to C<$ENV{'PERL_DL_DEBUG'}> if defined. |
396 | |
397 | For the DynaLoader developer/porter there is a similar debugging |
398 | variable added to the C code (see dlutils.c) and enabled if Perl was |
399 | built with the B<-DDEBUGGING> flag. This can also be set via the |
400 | PERL_DL_DEBUG environment variable. Set to 1 for minimal information or |
401 | higher for more. |
402 | |
403 | =item dl_findfile() |
404 | |
405 | Syntax: |
406 | |
407 | @filepaths = dl_findfile(@names) |
408 | |
409 | Determine the full paths (including file suffix) of one or more |
410 | loadable files given their generic names and optionally one or more |
411 | directories. Searches directories in @dl_library_path by default and |
412 | returns an empty list if no files were found. |
413 | |
414 | Names can be specified in a variety of platform independent forms. Any |
415 | names in the form B<-lname> are converted into F<libname.*>, where F<.*> is |
416 | an appropriate suffix for the platform. |
417 | |
418 | If a name does not already have a suitable prefix and/or suffix then |
419 | the corresponding file will be searched for by trying combinations of |
420 | prefix and suffix appropriate to the platform: "$name.o", "lib$name.*" |
421 | and "$name". |
422 | |
423 | If any directories are included in @names they are searched before |
c2960299 |
424 | @dl_library_path. Directories may be specified as B<-Ldir>. Any other |
425 | names are treated as filenames to be searched for. |
3b35bae3 |
426 | |
427 | Using arguments of the form C<-Ldir> and C<-lname> is recommended. |
428 | |
429 | Example: |
430 | |
431 | @dl_resolve_using = dl_findfile(qw(-L/usr/5lib -lposix)); |
432 | |
433 | |
434 | =item dl_expandspec() |
435 | |
436 | Syntax: |
437 | |
438 | $filepath = dl_expandspec($spec) |
439 | |
440 | Some unusual systems, such as VMS, require special filename handling in |
441 | order to deal with symbolic names for files (i.e., VMS's Logical Names). |
442 | |
443 | To support these systems a dl_expandspec() function can be implemented |
444 | either in the F<dl_*.xs> file or code can be added to the autoloadable |
c2960299 |
445 | dl_expandspec() function in F<DynaLoader.pm>. See F<DynaLoader.pm> for |
446 | more information. |
3b35bae3 |
447 | |
448 | =item dl_load_file() |
449 | |
450 | Syntax: |
451 | |
452 | $libref = dl_load_file($filename) |
453 | |
454 | Dynamically load $filename, which must be the path to a shared object |
455 | or library. An opaque 'library reference' is returned as a handle for |
456 | the loaded object. Returns undef on error. |
457 | |
458 | (On systems that provide a handle for the loaded object such as SunOS |
459 | and HPUX, $libref will be that handle. On other systems $libref will |
460 | typically be $filename or a pointer to a buffer containing $filename. |
461 | The application should not examine or alter $libref in any way.) |
462 | |
463 | This is function that does the real work. It should use the current |
464 | values of @dl_require_symbols and @dl_resolve_using if required. |
465 | |
466 | SunOS: dlopen($filename) |
467 | HP-UX: shl_load($filename) |
468 | Linux: dld_create_reference(@dl_require_symbols); dld_link($filename) |
469 | NeXT: rld_load($filename, @dl_resolve_using) |
470 | VMS: lib$find_image_symbol($filename,$dl_require_symbols[0]) |
471 | |
472 | |
473 | =item dl_find_symbol() |
474 | |
475 | Syntax: |
476 | |
477 | $symref = dl_find_symbol($libref, $symbol) |
478 | |
479 | Return the address of the symbol $symbol or C<undef> if not found. If the |
480 | target system has separate functions to search for symbols of different |
481 | types then dl_find_symbol() should search for function symbols first and |
482 | then other types. |
483 | |
484 | The exact manner in which the address is returned in $symref is not |
485 | currently defined. The only initial requirement is that $symref can |
486 | be passed to, and understood by, dl_install_xsub(). |
487 | |
488 | SunOS: dlsym($libref, $symbol) |
489 | HP-UX: shl_findsym($libref, $symbol) |
490 | Linux: dld_get_func($symbol) and/or dld_get_symbol($symbol) |
491 | NeXT: rld_lookup("_$symbol") |
492 | VMS: lib$find_image_symbol($libref,$symbol) |
493 | |
494 | |
495 | =item dl_undef_symbols() |
496 | |
497 | Example |
498 | |
499 | @symbols = dl_undef_symbols() |
500 | |
501 | Return a list of symbol names which remain undefined after load_file(). |
502 | Returns C<()> if not known. Don't worry if your platform does not provide |
c2960299 |
503 | a mechanism for this. Most do not need it and hence do not provide it, |
504 | they just return an empty list. |
3b35bae3 |
505 | |
506 | |
507 | =item dl_install_xsub() |
508 | |
509 | Syntax: |
510 | |
511 | dl_install_xsub($perl_name, $symref [, $filename]) |
512 | |
513 | Create a new Perl external subroutine named $perl_name using $symref as |
514 | a pointer to the function which implements the routine. This is simply |
515 | a direct call to newXSUB(). Returns a reference to the installed |
516 | function. |
517 | |
518 | The $filename parameter is used by Perl to identify the source file for |
519 | the function if required by die(), caller() or the debugger. If |
520 | $filename is not defined then "DynaLoader" will be used. |
521 | |
522 | |
523 | =item boostrap() |
524 | |
525 | Syntax: |
526 | |
527 | bootstrap($module) |
528 | |
529 | This is the normal entry point for automatic dynamic loading in Perl. |
530 | |
531 | It performs the following actions: |
532 | |
533 | =over 8 |
534 | |
535 | =item * |
536 | |
537 | locates an auto/$module directory by searching @INC |
538 | |
539 | =item * |
540 | |
541 | uses dl_findfile() to determine the filename to load |
542 | |
543 | =item * |
544 | |
545 | sets @dl_require_symbols to C<("boot_$module")> |
546 | |
547 | =item * |
548 | |
549 | executes an F<auto/$module/$module.bs> file if it exists |
550 | (typically used to add to @dl_resolve_using any files which |
551 | are required to load the module on the current platform) |
552 | |
553 | =item * |
554 | |
555 | calls dl_load_file() to load the file |
556 | |
557 | =item * |
558 | |
559 | calls dl_undef_symbols() and warns if any symbols are undefined |
560 | |
561 | =item * |
562 | |
563 | calls dl_find_symbol() for "boot_$module" |
564 | |
565 | =item * |
566 | |
567 | calls dl_install_xsub() to install it as "${module}::bootstrap" |
568 | |
569 | =item * |
570 | |
8e07c86e |
571 | calls &{"${module}::bootstrap"} to bootstrap the module (actually |
572 | it uses the function reference returned by dl_install_xsub for speed) |
3b35bae3 |
573 | |
574 | =back |
575 | |
576 | =back |
577 | |
578 | |
579 | =head1 AUTHOR |
580 | |
c2960299 |
581 | Tim Bunce, 11 August 1994. |
582 | |
3b35bae3 |
583 | This interface is based on the work and comments of (in no particular |
584 | order): Larry Wall, Robert Sanders, Dean Roehrich, Jeff Okamoto, Anno |
c2960299 |
585 | Siegel, Thomas Neumann, Paul Marquess, Charles Bailey, myself and others. |
3b35bae3 |
586 | |
587 | Larry Wall designed the elegant inherited bootstrap mechanism and |
588 | implemented the first Perl 5 dynamic loader using it. |
589 | |
3b35bae3 |
590 | =cut |