NAME¶
perlfaq2 - Obtaining and Learning about Perl
DESCRIPTION¶
This section of the FAQ answers questions about where to find source and
documentation for Perl, support, and related matters.
What machines support perl? Where do I get it?¶
The standard release of perl (the one maintained by the perl development team)
is distributed only in source code form. You can find the latest releases at
http://www.cpan.org/src/README.html .
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 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).
How can I get a binary version of perl?¶
(contributed by brian d foy)
ActiveState: Windows, Linux, Mac OS X, Solaris, AIX and HP-UX
http://www.activestate.com/
Sunfreeware.com: Solaris 2.5 to Solaris 10 (SPARC and x86)
http://www.sunfreeware.com/
Strawberry Perl: Windows, Perl 5.8.8 and 5.10.0
http://www.strawberryperl.com
IndigoPerl: Windows
http://indigostar.com/
I don't have a C compiler. How can I build my own Perl
interpreter?¶
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.
You might look around the net for a pre-built binary of Perl (or a C compiler!)
that meets your needs, though:
For Windows, Vanilla Perl (
http://vanillaperl.com/ ) and Strawberry Perl (
http://strawberryperl.com/ ) come with a bundled C compiler. ActivePerl is a
pre-compiled version of Perl ready-to-use.
For Sun systems, SunFreeware.com provides binaries of most popular applications,
including compilers and Perl.
I copied the perl binary from one machine to another, but scripts
don't work.¶
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 perlfaq8.
I grabbed the sources and tried to compile but gdbm/dynamic
loading/malloc/linking/... failed. How do I make it work?¶
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.
What modules and extensions are available for Perl? What is CPAN?
What does CPAN/src/... mean?¶
CPAN stands for Comprehensive Perl Archive Network, a multi-gigabyte archive
replicated on hundreds of 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, as of 2006, there are over ten 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 a free service and is not affiliated with O'Reilly Media.
Is there an ISO or ANSI certified version of Perl?¶
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.perl.org/ which has the complete
documentation in HTML and PDF format.
Many good books have been written about Perl--see the section later in perlfaq2
for more details.
Tutorial documents included in current or upcoming Perl releases include
perltoot for objects or perlboot for a beginner's approach to objects,
perlopentut for file opening semantics, perlreftut for managing references,
perlretut for regular expressions, perlthrtut for threads, perldebtut for
debugging, and perlxstut for linking C and Perl together. There may be more by
the time you read this. These URLs might also be useful:
http://perldoc.perl.org/
http://bookmarks.cpan.org/search.cgi?cat=Training%2FTutorials
What are the Perl newsgroups on Usenet? Where do I post
questions?¶
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
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.
Where should I post source code?¶
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.
Perl Books¶
There are many good books on Perl. See the perlbook documentation or (
http://books.perl.org ).
Which magazines have Perl content?¶
The Perl Review (
http://www.theperlreview.com ) focuses on Perl almost
completely (although it sometimes sneaks in an article about another
language). There's also
$foo Magazin, a German magazine
dedicated to Perl, at (
http://www.foo-magazin.de ).
The
Perl-Zeitung is a German-speaking magazine for Perl beginners (see
http://perl-zeitung.at.tf ).
Magazines that frequently carry quality articles on Perl include
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/ .
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. In 2006,
TPJ merged with Dr. Dobbs Journal
(online edition). To read old
TPJ articles, see
http://www.ddj.com/ or
brian d foy's index of online TPJ content (
http://www.perlmonks.org/index.pl?node_id=711609 ).
What mailing lists are there for Perl?¶
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/
Where are the archives for comp.lang.perl.misc?¶
The Google search engine now carries archived and searchable newsgroup content.
http://groups.google.com/group/comp.lang.perl.misc/topics
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.
Where can I buy a commercial version of perl?¶
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.
Where do I send bug reports?¶
(contributed by brian d foy)
First, ensure that you've found an actual bug. Second, ensure you've found an
actual bug.
If you've found a bug with the perl interpreter or one of the modules in the
standard library (those that come with Perl), you can use the perlbug utility
that comes with Perl (>= 5.004). It collects information about your
installation to include with your message, then sends the message to the right
place.
To determine if a module came with your version of Perl, you can use the
"Module::CoreList" module. It has the information about the modules
(with their versions) included with each release of Perl.
If "Module::CoreList" is not installed on your system, check out
http://perlpunks.de/corelist .
Every CPAN module has a bug tracker set up in RT,
http://rt.cpan.org . You can
submit bugs to RT either through its web interface or by email. To email a bug
report, send it to bug-<distribution-name>@rt.cpan.org . For example, if
you wanted to report a bug in "Business::ISBN", you could send a
message to bug-Business-ISBN@rt.cpan.org .
Some modules might have special reporting requirements, such as a Sourceforge or
Google Code tracking system, so you should check the module documentation too.
What is perl.com? Perl Mongers? pm.org? perl.org? cpan.org?¶
Perl.com (
http://www.perl.com/ ) used to be part of the O'Reilly Network, a
subsidiary of O'Reilly Media. Although it retains most of the original content
from its O'Reilly Network, it is now hosted by The Perl Foundation.
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. There are also many other sub-domains for special topics like
learning Perl, Perl news, jobs in Perl, such as:
http://www.perl.org/
http://learn.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 Mongers
website (
http://www.pm.org/ ) for more information about joining, starting,
or requesting services for a Perl user group.
CPAN, or the Comprehensive Perl Archive Network (
http://www.cpan.org/ ), is a
replicated, worldwide repository of Perl software. See
What is CPAN? in
perlfaq2.
AUTHOR AND COPYRIGHT¶
Copyright (c) 1997-2010 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.