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Perl 5.005_01 Documentation

For ease of access, the Perl manual has been split up into a number of sections:

perl		Perl overview (this section)
perldelta		Perl changes since previous version
perlfaq		Perl frequently asked questions
perltoc		Perl documentation table of contents

perldata		Perl data structures
perlsyn		Perl syntax
perlop		Perl operators and precedence
perlre		Perl regular expressions
perlrun		Perl execution and options
perlfunc		Perl builtin functions
perlvar		Perl predefined variables
perlsub		Perl subroutines
perlmod		Perl modules: how they work
perlmodlib		Perl modules: how to write and use
perlmodinstall	Perl modules: how to install from CPAN
perlform		Perl formats
perllocale		Perl locale support

perlref		Perl references
perldsc		Perl data structures intro
perllol		Perl data structures: lists of lists
perltoot		Perl OO tutorial
perlobj		Perl objects
perltie		Perl objects hidden behind simple variables
perlbot		Perl OO tricks and examples
perlipc		Perl interprocess communication

perldebug		Perl debugging
perldiag		Perl diagnostic messages
perlsec		Perl security
perltrap		Perl traps for the unwary
perlport		Perl portability guide
perlstyle		Perl style guide

perlpod		Perl plain old documentation
perlbook		Perl book information

perlembed		Perl ways to embed perl in your C or C++ application
perlapio		Perl internal IO abstraction interface
perlxs		Perl XS application programming interface
perlxstut		Perl XS tutorial
perlguts		Perl internal functions for those doing extensions
perlcall		Perl calling conventions from C

perlhist		Perl history records

(If you're intending to read these straight through for the first time, the suggested order will tend to reduce the number of forward references.)

By default, all of the above manpages are installed in the /usr/local/man/ directory.

Extensive additional documentation for Perl modules is available. The default configuration for perl will place this additional documentation in the /usr/local/lib/perl5/man directory (or else in the man subdirectory of the Perl library directory). Some of this additional documentation is distributed standard with Perl, but you'll also find documentation for third-party modules there.

You should be able to view Perl's documentation with your man(1) program by including the proper directories in the appropriate start-up files, or in the MANPATH environment variable. To find out where the configuration has installed the manpages, type:

perl -V:man.dir

If the directories have a common stem, such as /usr/local/man/man1 and /usr/local/man/man3, you need only to add that stem (/usr/local/man) to your man(1) configuration files or your MANPATH environment variable. If they do not share a stem, you'll have to add both stems.

If that doesn't work for some reason, you can still use the supplied perldoc script to view module information. You might also look into getting a replacement man program.

If something strange has gone wrong with your program and you're not sure where you should look for help, try the -w switch first. It will often point out exactly where the trouble is.

Full perl(1) documentation: perl

Reference Lists

About Perl

Perl is a language optimized for scanning arbitrary text files, extracting information from those text files, and printing reports based on that information. It's also a good language for many system management tasks. The language is intended to be practical (easy to use, efficient, complete) rather than beautiful (tiny, elegant, minimal).

Perl combines (in the author's opinion, anyway) some of the best features of C, sed, awk, and sh, so people familiar with those languages should have little difficulty with it. (Language historians will also note some vestiges of csh, Pascal, and even BASIC-PLUS.) Expression syntax corresponds quite closely to C expression syntax. Unlike most Unix utilities, Perl does not arbitrarily limit the size of your data--if you've got the memory, Perl can slurp in your whole file as a single string. Recursion is of unlimited depth. And the tables used by hashes (previously called "associative arrays") grow as necessary to prevent degraded performance. Perl uses sophisticated pattern matching techniques to scan large amounts of data very quickly. Although optimized for scanning text, Perl can also deal with binary data, and can make dbm files look like hashes. Setuid Perl scripts are safer than C programs through a dataflow tracing mechanism which prevents many stupid security holes.

If you have a problem that would ordinarily use sed or awk or sh, but it exceeds their capabilities or must run a little faster, and you don't want to write the silly thing in C, then Perl may be for you. There are also translators to turn your sed and awk scripts into Perl scripts.

But wait, there's more...

Perl version 5 is nearly a complete rewrite, and provides the following additional benefits:

Okay, that's definitely enough hype.