=head1 NAME perlfaq - frequently asked questions about Perl ($Date: 1998/07/20 23:12:17 $) =head1 DESCRIPTION This document is structured into the following sections: =over =item perlfaq: Structural overview of the FAQ. This document. =item L: General Questions About Perl Very general, high-level information about Perl. =item L: Obtaining and Learning about Perl Where to find source and documentation to Perl, support, and related matters. =item L: Programming Tools Programmer tools and programming support. =item L: Data Manipulation Manipulating numbers, dates, strings, arrays, hashes, and miscellaneous data issues. =item L: Files and Formats I/O and the "f" issues: filehandles, flushing, formats and footers. =item L: Regexps Pattern matching and regular expressions. =item L: General Perl Language Issues General Perl language issues that don't clearly fit into any of the other sections. =item L: System Interaction Interprocess communication (IPC), control over the user-interface (keyboard, screen and pointing devices). =item L: Networking Networking, the Internet, and a few on the web. =back =head2 Where to get this document This document is posted regularly to comp.lang.perl.announce and several other related newsgroups. It is available in a variety of formats from CPAN in the /CPAN/doc/FAQs/FAQ/ directory, or on the web at http://www.perl.com/perl/faq/ . =head2 How to contribute to this document You may mail corrections, additions, and suggestions to perlfaq-suggestions@perl.com . This alias should not be used to I FAQs. It's for fixing the current FAQ. =head2 What will happen if you mail your Perl programming problems to the authors Your questions will probably go unread, unless they're suggestions of new questions to add to the FAQ, in which case they should have gone to the perlfaq-suggestions@perl.com instead. You should have read section 2 of this faq. There you would have learned that comp.lang.perl.misc is the appropriate place to go for free advice. If your question is really important and you require a prompt and correct answer, you should hire a consultant. =head1 Credits When I first began the Perl FAQ in the late 80s, I never realized it would have grown to over a hundred pages, nor that Perl would ever become so popular and widespread. This document could not have been written without the tremendous help provided by Larry Wall and the rest of the Perl Porters. =head1 Author and Copyright Information Copyright (c) 1997, 1998 Tom Christiansen and Nathan Torkington. All rights reserved. =head2 Bundled Distributions When included as part of the Standard Version of Perl, or as part of its complete documentation whether printed or otherwise, this work may be distributed only under the terms of Perl's Artistic License. Any distribution of this file or derivatives thereof I of that package require that special arrangements be made with copyright holder. Irrespective of its distribution, all code examples in these files are hereby placed into the public domain. You are permitted and encouraged to use this code in your own programs for fun or for profit as you see fit. A simple comment in the code giving credit would be courteous but is not required. =head2 Disclaimer This information is offered in good faith and in the hope that it may be of use, but is not guaranteed to be correct, up to date, or suitable for any particular purpose whatsoever. The authors accept no liability in respect of this information or its use. =head1 Changes =over 4 =head 22/June/98 Significant changes throughout in preparation for the 5.005 release. =item 24/April/97 Style and whitespace changes from Chip, new question on reading one character at a time from a terminal using POSIX from Tom. =item 23/April/97 Added http://www.oasis.leo.org/perl/ to L. Style fix to L. Added floating point precision, fixed complex number arithmetic, cross-references, caveat for Text::Wrap, alternative answer for initial capitalizing, fixed incorrect regexp, added example of Tie::IxHash to L. Added example of passing and storing filehandles, added commify to L. Restored variable suicide, and added mass commenting to L. Added Net::Telnet, fixed backticks, added reader/writer pair to telnet question, added FindBin, grouped module questions together in L. Expanded caveats for the simple URL extractor, gave LWP example, added CGI security question, expanded on the mail address answer in L. =item 25/March/97 Added more info to the binary distribution section of L. Added Net::Telnet to L. Fixed typos in L. Added mail sending example to L. Added Merlyn's columns to L. =item 18/March/97 Added the DATE to the NAME section, indicating which sections have changed. Mentioned SIGPIPE and L in the forking open answer in L. Fixed description of a regular expression in L. =item 17/March/97 Version Various typos fixed throughout. Added new question on Perl BNF on L. =item Initial Release: 11/March/97 This is the initial release of version 3 of the FAQ; consequently there have been no changes since its initial release. =back