3 perlfaq2 - Obtaining and Learning about Perl ($Revision: 1.34 $, $Date: 2005/08/10 15:56:54 $)
7 This section of the FAQ answers questions about where to find
8 source and documentation for Perl, support, and
11 =head2 What machines support perl? Where do I get it?
13 The standard release of perl (the one maintained by the perl
14 development team) is distributed only in source code form. You
15 can find this at http://www.cpan.org/src/latest.tar.gz , which
16 is in a standard Internet format (a gzipped archive in POSIX tar format).
18 Perl builds and runs on a bewildering number of platforms. Virtually
19 all known and current Unix derivatives are supported (perl's native
20 platform), as are other systems like VMS, DOS, OS/2, Windows,
21 QNX, BeOS, OS X, MPE/iX and the Amiga.
23 Binary distributions for some proprietary platforms, including
24 Apple systems, can be found http://www.cpan.org/ports/ directory.
25 Because these are not part of the standard distribution, they may
26 and in fact do differ from the base perl port in a variety of ways.
27 You'll have to check their respective release notes to see just
28 what the differences are. These differences can be either positive
29 (e.g. extensions for the features of the particular platform that
30 are not supported in the source release of perl) or negative (e.g.
31 might be based upon a less current source release of perl).
33 =head2 How can I get a binary version of perl?
35 If you don't have a C compiler because your vendor for whatever
36 reasons did not include one with your system, the best thing to do is
37 grab a binary version of gcc from the net and use that to compile perl
38 with. CPAN only has binaries for systems that are terribly hard to
39 get free compilers for, not for Unix systems.
41 Some URLs that might help you are:
43 http://www.cpan.org/ports/
44 http://www.perl.com/pub/language/info/software.html
46 Someone looking for a perl for Win16 might look to Laszlo Molnar's djgpp
47 port in http://www.cpan.org/ports/#msdos , which comes with clear
48 installation instructions. A simple installation guide for MS-DOS using
49 Ilya Zakharevich's OS/2 port is available at
50 http://www.cs.ruu.nl/%7Epiet/perl5dos.html
51 and similarly for Windows 3.1 at http://www.cs.ruu.nl/%7Epiet/perlwin3.html .
53 =head2 I don't have a C compiler. How can I build my own Perl interpreter?
55 Since you don't have a C compiler, you're doomed and your vendor
56 should be sacrificed to the Sun gods. But that doesn't help you.
58 What you need to do is get a binary version of gcc for your system
59 first. Consult the Usenet FAQs for your operating system for
60 information on where to get such a binary version.
62 =head2 I copied the perl binary from one machine to another, but scripts don't work.
64 That's probably because you forgot libraries, or library paths differ.
65 You really should build the whole distribution on the machine it will
66 eventually live on, and then type C<make install>. Most other
67 approaches are doomed to failure.
69 One simple way to check that things are in the right place is to print out
70 the hard-coded @INC that perl looks through for libraries:
72 % perl -le 'print for @INC'
74 If this command lists any paths that don't exist on your system, then you
75 may need to move the appropriate libraries to these locations, or create
76 symbolic links, aliases, or shortcuts appropriately. @INC is also printed as
81 You might also want to check out
82 L<perlfaq8/"How do I keep my own module/library directory?">.
84 =head2 I grabbed the sources and tried to compile but gdbm/dynamic loading/malloc/linking/... failed. How do I make it work?
86 Read the F<INSTALL> file, which is part of the source distribution.
87 It describes in detail how to cope with most idiosyncrasies that the
88 Configure script can't work around for any given system or
91 =head2 What modules and extensions are available for Perl? What is CPAN? What does CPAN/src/... mean?
93 CPAN stands for Comprehensive Perl Archive Network, a ~1.2Gb archive
94 replicated on nearly 200 machines all over the world. CPAN contains
95 source code, non-native ports, documentation, scripts, and many
96 third-party modules and extensions, designed for everything from
97 commercial database interfaces to keyboard/screen control to web
98 walking and CGI scripts. The master web site for CPAN is
99 http://www.cpan.org/ and there is the CPAN Multiplexer at
100 http://www.cpan.org/CPAN.html which will choose a mirror near you
101 via DNS. See http://www.perl.com/CPAN (without a slash at the
102 end) for how this process works. Also, http://mirror.cpan.org/
103 has a nice interface to the http://www.cpan.org/MIRRORED.BY
106 See the CPAN FAQ at http://www.cpan.org/misc/cpan-faq.html for
107 answers to the most frequently asked questions about CPAN
108 including how to become a mirror.
110 CPAN/path/... is a naming convention for files available on CPAN
111 sites. CPAN indicates the base directory of a CPAN mirror, and the
112 rest of the path is the path from that directory to the file. For
113 instance, if you're using ftp://ftp.funet.fi/pub/languages/perl/CPAN
114 as your CPAN site, the file CPAN/misc/japh is downloadable as
115 ftp://ftp.funet.fi/pub/languages/perl/CPAN/misc/japh .
117 Considering that there are close to two thousand existing modules in
118 the archive, one probably exists to do nearly anything you can think of.
119 Current categories under CPAN/modules/by-category/ include Perl core
120 modules; development support; operating system interfaces; networking,
121 devices, and interprocess communication; data type utilities; database
122 interfaces; user interfaces; interfaces to other languages; filenames,
123 file systems, and file locking; internationalization and locale; world
124 wide web support; server and daemon utilities; archiving and
125 compression; image manipulation; mail and news; control flow
126 utilities; filehandle and I/O; Microsoft Windows modules; and
127 miscellaneous modules.
129 See http://www.cpan.org/modules/00modlist.long.html or
130 http://search.cpan.org/ for a more complete list of modules by category.
132 CPAN is not affiliated with O'Reilly Media.
134 =head2 Is there an ISO or ANSI certified version of Perl?
136 Certainly not. Larry expects that he'll be certified before Perl is.
138 =head2 Where can I get information on Perl?
140 The complete Perl documentation is available with the Perl distribution.
141 If you have Perl installed locally, you probably have the documentation
142 installed as well: type C<man perl> if you're on a system resembling Unix.
143 This will lead you to other important man pages, including how to set your
144 $MANPATH. If you're not on a Unix system, access to the documentation
145 will be different; for example, documentation might only be in HTML format. All
146 proper perl installations have fully-accessible documentation.
148 You might also try C<perldoc perl> in case your system doesn't
149 have a proper man command, or it's been misinstalled. If that doesn't
150 work, try looking in /usr/local/lib/perl5/pod for documentation.
152 If all else fails, consult http://perldoc.cpan.org/ or
153 http://www.perldoc.com/ both offer the complete documentation
156 Many good books have been written about Perl--see the section below
159 Tutorial documents are included in current or upcoming Perl releases
160 include L<perltoot> for objects or L<perlboot> for a beginner's
161 approach to objects, L<perlopentut> for file opening semantics,
162 L<perlreftut> for managing references, L<perlretut> for regular
163 expressions, L<perlthrtut> for threads, L<perldebtut> for debugging,
164 and L<perlxstut> for linking C and Perl together. There may be more
165 by the time you read this. The following URLs might also be of
168 http://perldoc.cpan.org/
169 http://www.perldoc.com/
170 http://bookmarks.cpan.org/search.cgi?cat=Training%2FTutorials
172 =head2 What are the Perl newsgroups on Usenet? Where do I post questions?
174 Several groups devoted to the Perl language are on Usenet:
176 comp.lang.perl.announce Moderated announcement group
177 comp.lang.perl.misc High traffic general Perl discussion
178 comp.lang.perl.moderated Moderated discussion group
179 comp.lang.perl.modules Use and development of Perl modules
180 comp.lang.perl.tk Using Tk (and X) from Perl
182 comp.infosystems.www.authoring.cgi Writing CGI scripts for the Web.
184 Some years ago, comp.lang.perl was divided into those groups, and
185 comp.lang.perl itself officially removed. While that group may still
186 be found on some news servers, it is unwise to use it, because
187 postings there will not appear on news servers which honour the
188 official list of group names. Use comp.lang.perl.misc for topics
189 which do not have a more-appropriate specific group.
191 There is also a Usenet gateway to Perl mailing lists sponsored by
192 perl.org at nntp://nntp.perl.org , a web interface to the same lists
193 at http://nntp.perl.org/group/ and these lists are also available
194 under the C<perl.*> hierarchy at http://groups.google.com . Other
195 groups are listed at http://lists.perl.org/ ( also known as
196 http://lists.cpan.org/ ).
198 A nice place to ask questions is the PerlMonks site,
199 http://www.perlmonks.org/ , or the Perl Beginners mailing list
200 http://lists.perl.org/showlist.cgi?name=beginners .
202 Note that none of the above are supposed to write your code for you:
203 asking questions about particular problems or general advice is fine,
204 but asking someone to write your code for free is not very cool.
206 =head2 Where should I post source code?
208 You should post source code to whichever group is most appropriate, but
209 feel free to cross-post to comp.lang.perl.misc. If you want to cross-post
210 to alt.sources, please make sure it follows their posting standards,
211 including setting the Followup-To header line to NOT include alt.sources;
212 see their FAQ ( http://www.faqs.org/faqs/alt-sources-intro/ ) for details.
214 If you're just looking for software, first use Google
215 ( http://www.google.com ), Google's usenet search interface
216 ( http://groups.google.com ), and CPAN Search ( http://search.cpan.org ).
217 This is faster and more productive than just posting a request.
221 A number of books on Perl and/or CGI programming are available. A few
222 of these are good, some are OK, but many aren't worth your money.
223 There is a list of these books, some with extensive reviews, at
224 http://books.perl.org/ .
226 The incontestably definitive reference book on Perl, written by
227 the creator of Perl, is now (Sept 2004) in its third edition:
229 Programming Perl (the "Camel Book"):
230 by Larry Wall, Tom Christiansen, and Jon Orwant
231 ISBN 0-596-00027-8 [3rd edition July 2000]
232 http://www.oreilly.com/catalog/pperl3/
233 (English, translations to several languages are also available)
235 The companion volume to the Camel containing thousands
236 of real-world examples, mini-tutorials, and complete programs is:
238 The Perl Cookbook (the "Ram Book"):
239 by Tom Christiansen and Nathan Torkington,
240 with Foreword by Larry Wall
241 ISBN 0-596-00313-7 [2nd Edition August 2003]
242 http://www.oreilly.com/catalog/perlckbk2/
244 If you're already a seasoned programmer, then the Camel Book might
245 suffice for you to learn Perl from. If you're not, check out the
248 Learning Perl (the "Llama Book")
249 by Randal L. Schwartz and Tom Phoenix
250 ISBN 0-596-00132-0 [3rd edition July 2001]
251 http://www.oreilly.com/catalog/lperl3/
253 And for more advanced information on writing larger programs,
254 presented in the same style as the Llama book, continue your education
255 with the Alpaca book:
257 Learning Perl Objects, References, and Modules (the "Alpaca Book")
258 by Randal L. Schwartz, with Tom Phoenix (foreword by Damian Conway)
259 ISBN 0-596-00478-8 [1st edition June 2003]
260 http://www.oreilly.com/catalog/lrnperlorm/
262 If you're not an accidental programmer, but a more serious and
263 possibly even degreed computer scientist who doesn't need as much
264 hand-holding as we try to provide in the Llama, please check out the
267 Perl: The Programmer's Companion
269 ISBN 0-471-97563-X [1997, 3rd printing Spring 1998]
270 http://www.wiley.com/compbooks/catalog/97563-X.htm
271 http://www.wiley.com/compbooks/chapman/perl/perltpc.html (errata etc)
273 If you are more at home in Windows the following is available
274 (though unfortunately rather dated).
276 Learning Perl on Win32 Systems (the "Gecko Book")
277 by Randal L. Schwartz, Erik Olson, and Tom Christiansen,
278 with foreword by Larry Wall
279 ISBN 1-56592-324-3 [1st edition August 1997]
280 http://www.oreilly.com/catalog/lperlwin/
282 Addison-Wesley ( http://www.awlonline.com/ ) and Manning
283 ( http://www.manning.com/ ) are also publishers of some fine Perl books
284 such as I<Object Oriented Programming with Perl> by Damian Conway and
285 I<Network Programming with Perl> by Lincoln Stein.
287 An excellent technical book discounter is Bookpool at
288 http://www.bookpool.com/ where a 30% discount or more is not unusual.
290 What follows is a list of the books that the FAQ authors found personally
291 useful. Your mileage may (but, we hope, probably won't) vary.
293 Recommended books on (or mostly on) Perl follow.
300 by Larry Wall, Tom Christiansen, and Jon Orwant
301 ISBN 0-596-00027-8 [3rd edition July 2000]
302 http://www.oreilly.com/catalog/pperl3/
304 Perl 5 Pocket Reference
306 ISBN 0-596-00032-4 [3rd edition May 2000]
307 http://www.oreilly.com/catalog/perlpr3/
310 by Ellen Siever, Stephan Spainhour, and Nathan Patwardhan
311 ISBN 1-56592-286-7 [1st edition December 1998]
312 http://www.oreilly.com/catalog/perlnut/
318 ISBN 1-59059-391-X [2nd edition August 2004]
319 http://apress.com/book/bookDisplay.html?bID=344
321 Elements of Programming with Perl
323 ISBN 1-884777-80-5 [1st edition October 1999]
324 http://www.manning.com/Johnson/
327 by Randal L. Schwartz and Tom Phoenix
328 ISBN 0-596-00132-0 [3rd edition July 2001]
329 http://www.oreilly.com/catalog/lperl3/
331 Learning Perl Objects, References, and Modules
332 by Randal L. Schwartz, with Tom Phoenix (foreword by Damian Conway)
333 ISBN 0-596-00478-8 [1st edition June 2003]
334 http://www.oreilly.com/catalog/lrnperlorm/
336 Learning Perl on Win32 Systems
337 by Randal L. Schwartz, Erik Olson, and Tom Christiansen,
338 with foreword by Larry Wall
339 ISBN 1-56592-324-3 [1st edition August 1997]
340 http://www.oreilly.com/catalog/lperlwin/
342 Perl: The Programmer's Companion
344 ISBN 0-471-97563-X [1997, 3rd printing Spring 1998]
345 http://www.wiley.com/compbooks/catalog/97563-X.htm
346 http://www.wiley.com/compbooks/chapman/perl/perltpc.html (errata etc)
349 by Eric Foster-Johnson
350 ISBN 1-55851-483-X [2nd edition September 2000]
351 http://www.pconline.com/~erc/perlbook.htm
353 MacPerl: Power and Ease
354 by Vicki Brown and Chris Nandor,
355 with foreword by Matthias Neeracher
356 ISBN 1-881957-32-2 [1st edition May 1998]
357 http://www.macperl.com/ptf_book/
361 Writing Perl Modules for CPAN
363 ISBN 1-59059-018-X [1st edition Aug 2002]
364 http://apress.com/book/bookDisplay.html?bID=14
367 by Tom Christiansen and Nathan Torkington
368 with foreword by Larry Wall
369 ISBN 1-56592-243-3 [1st edition August 1998]
370 http://www.oreilly.com/catalog/cookbook/
372 Effective Perl Programming
374 ISBN 0-201-41975-0 [1st edition 1998]
377 Real World SQL Server Administration with Perl
379 ISBN 1-59059-097-X [1st edition July 2003]
380 http://apress.com/book/bookDisplay.html?bID=171
384 Perl 6 Now: The Core Ideas Illustrated with Perl 5
386 ISBN 1-59059-395-2 [1st edition December 2004
387 http://apress.com/book/bookDisplay.html?bID=355
389 Mastering Regular Expressions
390 by Jeffrey E. F. Friedl
391 ISBN 0-596-00289-0 [2nd edition July 2002]
392 http://www.oreilly.com/catalog/regex2/
394 Network Programming with Perl
396 ISBN 0-201-61571-1 [1st edition 2001]
397 http://www.awlonline.com/
401 with foreword by Randal L. Schwartz
402 ISBN 1-884777-79-1 [1st edition August 1999]
403 http://www.manning.com/Conway/
405 Data Munging with Perl
407 ISBN 1-930110-00-6 [1st edition 2001]
408 http://www.manning.com/cross
411 by Steve Lidie and Nancy Walsh
412 ISBN 1-56592-716-8 [1st edition January 2002]
413 http://www.oreilly.com/catalog/mastperltk/
415 Extending and Embedding Perl
416 by Tim Jenness and Simon Cozens
417 ISBN 1-930110-82-0 [1st edition August 2002]
418 http://www.manning.com/jenness
420 Perl Debugger Pocket Reference
422 ISBN 0-596-00503-2 [1st edition January 2004]
423 http://www.oreilly.com/catalog/perldebugpr/
427 =head2 Perl in Magazines
429 The first (and for a long time, only) periodical devoted to All Things Perl,
430 I<The Perl Journal> contains tutorials, demonstrations, case studies,
431 announcements, contests, and much more. I<TPJ> has columns on web
432 development, databases, Win32 Perl, graphical programming, regular
433 expressions, and networking, and sponsors the Obfuscated Perl Contest
434 and the Perl Poetry Contests. Beginning in November 2002, TPJ moved to a
435 reader-supported monthly e-zine format in which subscribers can download
436 issues as PDF documents. For more details on TPJ, see http://www.tpj.com/
438 Beyond this, magazines that frequently carry quality articles on
439 Perl are I<The Perl Review> ( http://www.theperlreview.com ),
440 I<Unix Review> ( http://www.unixreview.com/ ),
441 I<Linux Magazine> ( http://www.linuxmagazine.com/ ),
442 and Usenix's newsletter/magazine to its members, I<login:>
443 ( http://www.usenix.org/ )
445 The Perl columns of Randal L. Schwartz are available on the web at
446 http://www.stonehenge.com/merlyn/WebTechniques/ ,
447 http://www.stonehenge.com/merlyn/UnixReview/ , and
448 http://www.stonehenge.com/merlyn/LinuxMag/ .
450 =head2 Perl on the Net: FTP and WWW Access
452 To get the best performance, pick a site from the list at
453 http://www.cpan.org/SITES.html . From there you can find the quickest
456 You may also use xx.cpan.org where "xx" is the 2-letter country code
457 for your domain; e.g. Australia would use au.cpan.org. [Note: This
458 only applies to countries that host at least one mirror.]
460 =head2 What mailing lists are there for Perl?
462 Most of the major modules (Tk, CGI, libwww-perl) have their own
463 mailing lists. Consult the documentation that came with the module for
464 subscription information.
466 A comprehensive list of Perl related mailing lists can be found at:
468 http://lists.perl.org/
470 =head2 Archives of comp.lang.perl.misc
472 The Google search engine now carries archived and searchable newsgroup
475 http://groups.google.com/groups?group=comp.lang.perl.misc
477 If you have a question, you can be sure someone has already asked the
478 same question at some point on c.l.p.m. It requires some time and patience
479 to sift through all the content but often you will find the answer you
482 =head2 Where can I buy a commercial version of perl?
484 In a real sense, perl already I<is> commercial software: it has a license
485 that you can grab and carefully read to your manager. It is distributed
486 in releases and comes in well-defined packages. There is a very large
487 user community and an extensive literature. The comp.lang.perl.*
488 newsgroups and several of the mailing lists provide free answers to your
489 questions in near real-time. Perl has traditionally been supported by
490 Larry, scores of software designers and developers, and myriad
491 programmers, all working for free to create a useful thing to make life
494 However, these answers may not suffice for managers who require a
495 purchase order from a company whom they can sue should anything go awry.
496 Or maybe they need very serious hand-holding and contractual obligations.
497 Shrink-wrapped CDs with perl on them are available from several sources if
498 that will help. For example, many Perl books include a distribution of perl,
499 as do the O'Reilly Perl Resource Kits (in both the Unix flavor
500 and in the proprietary Microsoft flavor); the free Unix distributions
501 also all come with perl.
503 =head2 Where do I send bug reports?
505 If you are reporting a bug in the perl interpreter or the modules
506 shipped with Perl, use the I<perlbug> program in the Perl distribution or
507 mail your report to perlbug@perl.org or at http://rt.perl.org/perlbug/ .
509 For Perl modules, you can submit bug reports to the Request Tracker set
510 up at http://rt.cpan.org .
512 If you are posting a bug with a non-standard port (see the answer to
513 "What platforms is perl available for?"), a binary distribution, or a
514 non-standard module (such as Tk, CGI, etc), then please see the
515 documentation that came with it to determine the correct place to post
518 Read the perlbug(1) man page (perl5.004 or later) for more information.
520 =head2 What is perl.com? Perl Mongers? pm.org? perl.org? cpan.org?
522 Perl.com at http://www.perl.com/ is part of the O'Reilly Network, a
523 subsidiary of O'Reilly Media.
525 The Perl Foundation is an advocacy organization for the Perl language
526 which maintains the web site http://www.perl.org/ as a general
527 advocacy site for the Perl language. It uses the domain to provide
528 general support services to the Perl community, including the hosting
529 of mailing lists, web sites, and other services. The web site
530 http://www.perl.org/ is a general advocacy site for the Perl language,
531 and there are many other sub-domains for special topics, such as
533 http://learn.perl.org/
535 http://jobs.perl.org/
536 http://lists.perl.org/
538 Perl Mongers uses the pm.org domain for services related to Perl user
539 groups, including the hosting of mailing lists and web sites. See the
540 Perl user group web site at http://www.pm.org/ for more information about
541 joining, starting, or requesting services for a Perl user group.
543 http://www.cpan.org/ is the Comprehensive Perl Archive Network,
544 a replicated worldwide repository of Perl software, see
545 the I<What is CPAN?> question earlier in this document.
547 =head1 AUTHOR AND COPYRIGHT
549 Copyright (c) 1997-2005 Tom Christiansen, Nathan Torkington, and
550 other authors as noted. All rights reserved.
552 This documentation is free; you can redistribute it and/or modify it
553 under the same terms as Perl itself.
555 Irrespective of its distribution, all code examples here are in the public
556 domain. You are permitted and encouraged to use this code and any
557 derivatives thereof in your own programs for fun or for profit as you
558 see fit. A simple comment in the code giving credit to the FAQ would
559 be courteous but is not required.