perlfaq2 - Obtaining and Learning about Perl
perlfaq2 - Obtaining and Learning about Perl ($Revision: 1.31 $, $Date: 2005/01/31 15:54:44 $)
This section of the FAQ answers questions about where to find
source and documentation for Perl, support, and
related matters.
The standard release of Perl (the one maintained by the perl
development team) is distributed only in source code form. You
can find this at http://www.cpan.org/src/latest.tar.gz , which
is in a standard Internet format (a gzipped archive in POSIX tar format).
Perl builds and runs on a bewildering number of platforms. Virtually
all known and current Unix derivatives are supported (Perl's native
platform), as are other systems like VMS, DOS, OS/2, Windows,
QNX, BeOS, OS X, MPE/iX and the Amiga.
Binary distributions for some proprietary platforms, including
Apple systems, can be found http://www.cpan.org/ports/ directory.
Because these are not part of the standard distribution, they may
and in fact do differ from the base Perl port in a variety of ways.
You'll have to check their respective release notes to see just
what the differences are. These differences can be either positive
(e.g. extensions for the features of the particular platform that
are not supported in the source release of perl) or negative (e.g.
might be based upon a less current source release of perl).
If you don't have a C compiler because your vendor for whatever
reasons did not include one with your system, the best thing to do is
grab a binary version of gcc from the net and use that to compile perl
with. CPAN only has binaries for systems that are terribly hard to
get free compilers for, not for Unix systems.
Some URLs that might help you are:
http://www.cpan.org/ports/
http://www.perl.com/pub/language/info/software.html
Someone looking for a Perl for Win16 might look to Laszlo Molnar's djgpp
port in http://www.cpan.org/ports/#msdos , which comes with clear
installation instructions. A simple installation guide for MS-DOS using
Ilya Zakharevich's OS/2 port is available at
http://www.cs.ruu.nl/%7Epiet/perl5dos.html
and similarly for Windows 3.1 at http://www.cs.ruu.nl/%7Epiet/perlwin3.html .
Since you don't have a C compiler, you're doomed and your vendor
should be sacrificed to the Sun gods. But that doesn't help you.
What you need to do is get a binary version of gcc for your system
first. Consult the Usenet FAQs for your operating system for
information on where to get such a binary version.
That's probably because you forgot libraries, or library paths differ.
You really should build the whole distribution on the machine it will
eventually live on, and then type make install. Most other
approaches are doomed to failure.
One simple way to check that things are in the right place is to print out
the hard-coded @INC that perl looks through for libraries:
% perl -le 'print for @INC'
If this command lists any paths that don't exist on your system, then you
may need to move the appropriate libraries to these locations, or create
symbolic links, aliases, or shortcuts appropriately. @INC is also printed as
part of the output of
% perl -V
You might also want to check out
How do I keep my own module/library directory? in the perlfaq8 manpage.
Read the INSTALL file, which is part of the source distribution.
It describes in detail how to cope with most idiosyncrasies that the
Configure script can't work around for any given system or
architecture.
CPAN stands for Comprehensive Perl Archive Network, a ~1.2Gb archive
replicated on nearly 200 machines all over the world. CPAN contains
source code, non-native ports, documentation, scripts, and many
third-party modules and extensions, designed for everything from
commercial database interfaces to keyboard/screen control to web
walking and CGI scripts. The master web site for CPAN is
http://www.cpan.org/ and there is the CPAN Multiplexer at
http://www.cpan.org/CPAN.html which will choose a mirror near you
via DNS. See http://www.perl.com/CPAN (without a slash at the
end) for how this process works. Also, http://mirror.cpan.org/
has a nice interface to the http://www.cpan.org/MIRRORED.BY
mirror directory.
See the CPAN FAQ at http://www.cpan.org/misc/cpan-faq.html for
answers to the most frequently asked questions about CPAN
including how to become a mirror.
CPAN/path/... is a naming convention for files available on CPAN
sites. CPAN indicates the base directory of a CPAN mirror, and the
rest of the path is the path from that directory to the file. For
instance, if you're using ftp://ftp.funet.fi/pub/languages/perl/CPAN
as your CPAN site, the file CPAN/misc/japh is downloadable as
ftp://ftp.funet.fi/pub/languages/perl/CPAN/misc/japh .
Considering that there are close to two thousand existing modules in
the archive, one probably exists to do nearly anything you can think of.
Current categories under CPAN/modules/by-category/ include Perl core
modules; development support; operating system interfaces; networking,
devices, and interprocess communication; data type utilities; database
interfaces; user interfaces; interfaces to other languages; filenames,
file systems, and file locking; internationalization and locale; world
wide web support; server and daemon utilities; archiving and
compression; image manipulation; mail and news; control flow
utilities; filehandle and I/O; Microsoft Windows modules; and
miscellaneous modules.
See http://www.cpan.org/modules/00modlist.long.html or
http://search.cpan.org/ for a more complete list of modules by category.
CPAN is not affiliated with O'Reilly Media.
Certainly not. Larry expects that he'll be certified before Perl is.
The complete Perl documentation is available with the Perl distribution.
If you have Perl installed locally, you probably have the documentation
installed as well: type man perl if you're on a system resembling Unix.
This will lead you to other important man pages, including how to set your
$MANPATH. If you're not on a Unix system, access to the documentation
will be different; for example, documentation might only be in HTML format. All
proper Perl installations have fully-accessible documentation.
You might also try perldoc perl in case your system doesn't
have a proper man command, or it's been misinstalled. If that doesn't
work, try looking in /usr/local/lib/perl5/pod for documentation.
If all else fails, consult http://perldoc.cpan.org/ or
http://www.perldoc.com/ both offer the complete documentation
in html format.
Many good books have been written about Perl--see the section below
for more details.
Tutorial documents are included in current or upcoming Perl releases
include the perltoot manpage for objects or the perlboot manpage for a beginner's
approach to objects, the perlopentut manpage for file opening semantics,
the perlreftut manpage for managing references, the perlretut manpage for regular
expressions, the perlthrtut manpage for threads, the perldebtut manpage for debugging,
and the perlxstut manpage for linking C and Perl together. There may be more
by the time you read this. The following URLs might also be of
assistance:
http://perldoc.cpan.org/
http://www.perldoc.com/
http://bookmarks.cpan.org/search.cgi?cat=Training%2FTutorials
Several groups devoted to the Perl language are on Usenet:
comp.lang.perl.announce Moderated announcement group
comp.lang.perl.misc High traffic general Perl discussion
comp.lang.perl.moderated Moderated discussion group
comp.lang.perl.modules Use and development of Perl modules
comp.lang.perl.tk Using Tk (and X) from Perl
comp.infosystems.www.authoring.cgi Writing CGI scripts for the Web.
Some years ago, comp.lang.perl was divided into those groups, and
comp.lang.perl itself officially removed. While that group may still
be found on some news servers, it is unwise to use it, because
postings there will not appear on news servers which honour the
official list of group names. Use comp.lang.perl.misc for topics
which do not have a more-appropriate specific group.
There is also a Usenet gateway to Perl mailing lists sponsored by
perl.org at nntp://nntp.perl.org , a web interface to the same lists
at http://nntp.perl.org/group/ and these lists are also available
under the perl.* hierarchy at http://groups.google.com . Other
groups are listed at http://lists.perl.org/ ( also known as
http://lists.cpan.org/ ).
A nice place to ask questions is the PerlMonks site,
http://www.perlmonks.org/ , or the Perl Beginners mailing list
http://lists.perl.org/showlist.cgi?name=beginners .
Note that none of the above are supposed to write your code for you:
asking questions about particular problems or general advice is fine,
but asking someone to write your code for free is not very cool.
You should post source code to whichever group is most appropriate, but
feel free to cross-post to comp.lang.perl.misc. If you want to cross-post
to alt.sources, please make sure it follows their posting standards,
including setting the Followup-To header line to NOT include alt.sources;
see their FAQ ( http://www.faqs.org/faqs/alt-sources-intro/ ) for details.
If you're just looking for software, first use Google
( http://www.google.com ), Google's usenet search interface
( http://groups.google.com ), and CPAN Search ( http://search.cpan.org ).
This is faster and more productive than just posting a request.
A number of books on Perl and/or CGI programming are available. A few
of these are good, some are OK, but many aren't worth your money.
There is a list of these books, some with extensive reviews, at
http://books.perl.org/ .
The incontestably definitive reference book on Perl, written by
the creator of Perl, is now (Sept 2004) in its third edition:
Programming Perl (the "Camel Book"):
by Larry Wall, Tom Christiansen, and Jon Orwant
ISBN 0-596-00027-8 [3rd edition July 2000]
http://www.oreilly.com/catalog/pperl3/
(English, translations to several languages are also available)
The companion volume to the Camel containing thousands
of real-world examples, mini-tutorials, and complete programs is:
The Perl Cookbook (the "Ram Book"):
by Tom Christiansen and Nathan Torkington,
with Foreword by Larry Wall
ISBN 0-596-00313-7 [2nd Edition August 2003]
http://www.oreilly.com/catalog/perlckbk2/
If you're already a seasoned programmer, then the Camel Book might
suffice for you to learn Perl from. If you're not, check out the
Llama book:
Learning Perl (the "Llama Book")
by Randal L. Schwartz and Tom Phoenix
ISBN 0-596-00132-0 [3rd edition July 2001]
http://www.oreilly.com/catalog/lperl3/
And for more advanced information on writing larger programs,
presented in the same style as the Llama book, continue your education
with the Alpaca book:
Learning Perl Objects, References, and Modules (the "Alpaca Book")
by Randal L. Schwartz, with Tom Phoenix (foreword by Damian Conway)
ISBN 0-596-00478-8 [1st edition June 2003]
http://www.oreilly.com/catalog/lrnperlorm/
If you're not an accidental programmer, but a more serious and
possibly even degreed computer scientist who doesn't need as much
hand-holding as we try to provide in the Llama, please check out the
delightful book
Perl: The Programmer's Companion
by Nigel Chapman
ISBN 0-471-97563-X [1997, 3rd printing Spring 1998]
http://www.wiley.com/compbooks/catalog/97563-X.htm
http://www.wiley.com/compbooks/chapman/perl/perltpc.html (errata etc)
If you are more at home in Windows the following is available
(though unfortunately rather dated).
Learning Perl on Win32 Systems (the "Gecko Book")
by Randal L. Schwartz, Erik Olson, and Tom Christiansen,
with foreword by Larry Wall
ISBN 1-56592-324-3 [1st edition August 1997]
http://www.oreilly.com/catalog/lperlwin/
Addison-Wesley ( http://www.awlonline.com/ ) and Manning
( http://www.manning.com/ ) are also publishers of some fine Perl books
such as Object Oriented Programming with Perl by Damian Conway and
Network Programming with Perl by Lincoln Stein.
An excellent technical book discounter is Bookpool at
http://www.bookpool.com/ where a 30% discount or more is not unusual.
What follows is a list of the books that the FAQ authors found personally
useful. Your mileage may (but, we hope, probably won't) vary.
Recommended books on (or mostly on) Perl follow.
- References
-
Programming Perl
by Larry Wall, Tom Christiansen, and Jon Orwant
ISBN 0-596-00027-8 [3rd edition July 2000]
http://www.oreilly.com/catalog/pperl3/
-
Perl 5 Pocket Reference
by Johan Vromans
ISBN 0-596-00032-4 [3rd edition May 2000]
http://www.oreilly.com/catalog/perlpr3/
-
Perl in a Nutshell
by Ellen Siever, Stephan Spainhour, and Nathan Patwardhan
ISBN 1-56592-286-7 [1st edition December 1998]
http://www.oreilly.com/catalog/perlnut/
- Tutorials
-
Beginning Perl
by James Lee
ISBN 1-59059-391-X [2nd edition August 2004]
http://apress.com/book/bookDisplay.html?bID=344
-
Elements of Programming with Perl
by Andrew L. Johnson
ISBN 1-884777-80-5 [1st edition October 1999]
http://www.manning.com/Johnson/
-
Learning Perl
by Randal L. Schwartz and Tom Phoenix
ISBN 0-596-00132-0 [3rd edition July 2001]
http://www.oreilly.com/catalog/lperl3/
-
Learning Perl Objects, References, and Modules
by Randal L. Schwartz, with Tom Phoenix (foreword by Damian Conway)
ISBN 0-596-00478-8 [1st edition June 2003]
http://www.oreilly.com/catalog/lrnperlorm/
-
Learning Perl on Win32 Systems
by Randal L. Schwartz, Erik Olson, and Tom Christiansen,
with foreword by Larry Wall
ISBN 1-56592-324-3 [1st edition August 1997]
http://www.oreilly.com/catalog/lperlwin/
-
Perl: The Programmer's Companion
by Nigel Chapman
ISBN 0-471-97563-X [1997, 3rd printing Spring 1998]
http://www.wiley.com/compbooks/catalog/97563-X.htm
http://www.wiley.com/compbooks/chapman/perl/perltpc.html (errata etc)
-
Cross-Platform Perl
by Eric Foster-Johnson
ISBN 1-55851-483-X [2nd edition September 2000]
http://www.pconline.com/~erc/perlbook.htm
-
MacPerl: Power and Ease
by Vicki Brown and Chris Nandor,
with foreword by Matthias Neeracher
ISBN 1-881957-32-2 [1st edition May 1998]
http://www.macperl.com/ptf_book/
- Task-Oriented
-
Writing Perl Modules for CPAN
by Sam Tregar
ISBN 1-59059-018-X [1st edition Aug 2002]
http://apress.com/book/bookDisplay.html?bID=14
-
The Perl Cookbook
by Tom Christiansen and Nathan Torkington
with foreword by Larry Wall
ISBN 1-56592-243-3 [1st edition August 1998]
http://www.oreilly.com/catalog/cookbook/
-
Effective Perl Programming
by Joseph Hall
ISBN 0-201-41975-0 [1st edition 1998]
http://www.awl.com/
-
Real World SQL Server Administration with Perl
by Linchi Shea
ISBN 1-59059-097-X [1st edition July 2003]
http://apress.com/book/bookDisplay.html?bID=171
- Special Topics
-
Perl 6 Now: The Core Ideas Illustrated with Perl 5
by Scott Walters
ISBN 1-59059-395-2 [1st edition December 2004
http://apress.com/book/bookDisplay.html?bID=355
Mastering Regular Expressions
by Jeffrey E. F. Friedl
ISBN 0-596-00289-0 [2nd edition July 2002]
http://www.oreilly.com/catalog/regex2/
-
Network Programming with Perl
by Lincoln Stein
ISBN 0-201-61571-1 [1st edition 2001]
http://www.awlonline.com/
-
Object Oriented Perl
Damian Conway
with foreword by Randal L. Schwartz
ISBN 1-884777-79-1 [1st edition August 1999]
http://www.manning.com/Conway/
-
Data Munging with Perl
Dave Cross
ISBN 1-930110-00-6 [1st edition 2001]
http://www.manning.com/cross
-
Mastering Perl/Tk
by Steve Lidie and Nancy Walsh
ISBN 1-56592-716-8 [1st edition January 2002]
http://www.oreilly.com/catalog/mastperltk/
-
Extending and Embedding Perl
by Tim Jenness and Simon Cozens
ISBN 1-930110-82-0 [1st edition August 2002]
http://www.manning.com/jenness
-
Perl Debugger Pocket Reference
by Richard Foley
ISBN 0-596-00503-2 [1st edition January 2004]
http://www.oreilly.com/catalog/perldebugpr/
The first (and for a long time, only) periodical devoted to All Things Perl,
The Perl Journal contains tutorials, demonstrations, case studies,
announcements, contests, and much more. TPJ has columns on web
development, databases, Win32 Perl, graphical programming, regular
expressions, and networking, and sponsors the Obfuscated Perl Contest
and the Perl Poetry Contests. Beginning in November 2002, TPJ moved to a
reader-supported monthly e-zine format in which subscribers can download
issues as PDF documents. For more details on TPJ, see http://www.tpj.com/
Beyond this, magazines that frequently carry quality articles on
Perl are The Perl Review ( http://www.theperlreview.com ),
Unix Review ( http://www.unixreview.com/ ),
Linux Magazine ( http://www.linuxmagazine.com/ ),
and Usenix's newsletter/magazine to its members, login:
( http://www.usenix.org/ )
The Perl columns of Randal L. Schwartz are available on the web at
http://www.stonehenge.com/merlyn/WebTechniques/ ,
http://www.stonehenge.com/merlyn/UnixReview/ , and
http://www.stonehenge.com/merlyn/LinuxMag/ .
To get the best performance, pick a site from the list at
http://www.cpan.org/SITES.html . From there you can find the quickest
site for you.
You may also use xx.cpan.org where ``xx'' is the 2-letter country code
for your domain; e.g. Australia would use au.cpan.org. [Note: This
only applies to countries that host at least one mirror.]
Most of the major modules (Tk, CGI, libwww-perl) have their own
mailing lists. Consult the documentation that came with the module for
subscription information.
A comprehensive list of Perl related mailing lists can be found at:
http://lists.perl.org/
The Google search engine now carries archived and searchable newsgroup
content.
http://groups.google.com/groups?group=comp.lang.perl.misc
If you have a question, you can be sure someone has already asked the
same question at some point on c.l.p.m. It requires some time and patience
to sift through all the content but often you will find the answer you
seek.
In a real sense, Perl already is commercial software: it has a license
that you can grab and carefully read to your manager. It is distributed
in releases and comes in well-defined packages. There is a very large
user community and an extensive literature. The comp.lang.perl.*
newsgroups and several of the mailing lists provide free answers to your
questions in near real-time. Perl has traditionally been supported by
Larry, scores of software designers and developers, and myriad
programmers, all working for free to create a useful thing to make life
better for everyone.
However, these answers may not suffice for managers who require a
purchase order from a company whom they can sue should anything go awry.
Or maybe they need very serious hand-holding and contractual obligations.
Shrink-wrapped CDs with Perl on them are available from several sources if
that will help. For example, many Perl books include a distribution of Perl,
as do the O'Reilly Perl Resource Kits (in both the Unix flavor
and in the proprietary Microsoft flavor); the free Unix distributions
also all come with Perl.
If you are reporting a bug in the perl interpreter or the modules
shipped with Perl, use the perlbug program in the Perl distribution or
mail your report to perlbug@perl.org .
If you are posting a bug with a non-standard port (see the answer to
``What platforms is Perl available for?''), a binary distribution, or a
non-standard module (such as Tk, CGI, etc), then please see the
documentation that came with it to determine the correct place to post
bugs.
Read the perlbug(1) man page (perl5.004 or later) for more information.
Perl.com at http://www.perl.com/ is part of the O'Reilly Network, a
subsidiary of O'Reilly Media.
The Perl Foundation is an advocacy organization for the Perl language
which maintains the web site http://www.perl.org/ as a general
advocacy site for the Perl language. It uses the domain to provide
general support services to the Perl community, including the hosting
of mailing lists, web sites, and other services. The web site
http://www.perl.org/ is a general advocacy site for the Perl language,
and there are many other sub-domains for special topics, such as
http://learn.perl.org/
http://use.perl.org/
http://jobs.perl.org/
http://lists.perl.org/
Perl Mongers uses the pm.org domain for services related to Perl user
groups, including the hosting of mailing lists and web sites. See the
Perl user group web site at http://www.pm.org/ for more information about
joining, starting, or requesting services for a Perl user group.
http://www.cpan.org/ is the Comprehensive Perl Archive Network,
a replicated worlwide repository of Perl software, see
the What is CPAN? question earlier in this document.
Copyright (c) 1997-2005 Tom Christiansen, Nathan Torkington, and
other authors as noted. All rights reserved.
This documentation is free; you can redistribute it and/or modify it
under the same terms as Perl itself.
Irrespective of its distribution, all code examples here are in the public
domain. You are permitted and encouraged to use this code and any
derivatives thereof in your own programs for fun or for profit as you
see fit. A simple comment in the code giving credit to the FAQ would
be courteous but is not required.