=head1 NAME perl - Practical Extraction and Report Language =head1 SYNOPSIS B S<[ B<-sTtuUWX> ]> S<[ B<-hv> ] [ B<-V>[:I] ]> S<[ B<-cw> ] [ B<-d>[B][:I] ] [ B<-D>[I] ]> S<[ B<-pna> ] [ B<-F>I ] [ B<-l>[I] ] [ B<-0>[I] ]> S<[ B<-I>I ] [ B<-m>[B<->]I ] [ B<-M>[B<->]I<'module...'> ] [ B<-f> ]> S<[ B<-C [I] >]> S<[ B<-P> ]> S<[ B<-S> ]> S<[ B<-x>[I] ]> S<[ B<-i>[I] ]> S<[ B<-e> I<'command'> ] [ B<--> ] [ I ] [ I ]...> If you're new to Perl, you should start with L, which is a general intro for beginners and provides some background to help you navigate the rest of Perl's extensive documentation. For ease of access, the Perl manual has been split up into several sections. =head2 Overview perl Perl overview (this section) Perl の概要 (この節です) perlintro Perl introduction for beginners Perl の初心者向けイントロダクション perltoc Perl documentation table of contents Perl ドキュメントの目次 =head2 Tutorials perlreftut Perl references short introduction Perl リファレンスの簡単な紹介 perldsc Perl data structures intro Perl データ構造紹介 perllol Perl data structures: arrays of arrays Perl データ構造: 配列の配列 perlrequick Perl regular expressions quick start Perl はやわかり正規表現 perlretut Perl regular expressions tutorial Perl 正規表現チュートリアル perlboot Perl OO tutorial for beginners Perl オブジェクト指向導入編 perltoot Perl OO tutorial, part 1 Perl オブジェクト指向パート１ perltooc Perl OO tutorial, part 2 Perl オブジェクト指向パート２ perlbot Perl OO tricks and examples Perl オブジェクト指向, 仕掛けと例 perlstyle Perl style guide Perl スタイルガイド perlcheat Perl cheat sheet Perl チートシート perltrap Perl traps for the unwary Perl 落とし穴と注意点 perldebtut Perl debugging tutorial Perl デバッグチュートリアル perlfaq Perl frequently asked questions Perl に関するよく聞かれる質問 perlfaq1 General Questions About Perl Perl に関する関する一般的な質問 perlfaq2 Obtaining and Learning about Perl Perl の取得と学習 perlfaq3 Programming Tools プログラミングツール perlfaq4 Data Manipulation データ操作 perlfaq5 Files and Formats ファイルとフォーマット perlfaq6 Regexes 正規表現 perlfaq7 Perl Language Issues Perl 言語について perlfaq8 System Interaction システムとの連係 perlfaq9 Networking ネットワーク =head2 Reference Manual perlsyn Perl syntax perldata Perl data structures perlop Perl operators and precedence perlsub Perl subroutines perlfunc Perl built-in functions perlopentut Perl open() tutorial perlpacktut Perl pack() and unpack() tutorial perlpod Perl plain old documentation perlpodspec Perl plain old documentation format specification perlrun Perl execution and options perldiag Perl diagnostic messages perllexwarn Perl warnings and their control perldebug Perl debugging perlvar Perl predefined variables perlre Perl regular expressions, the rest of the story perlreref Perl regular expressions quick reference perlref Perl references, the rest of the story perlform Perl formats perlobj Perl objects perltie Perl objects hidden behind simple variables perldbmfilter Perl DBM filters perlipc Perl interprocess communication perlfork Perl fork() information perlnumber Perl number semantics perlthrtut Perl threads tutorial Perl スレッドチュートリアル perlothrtut Old Perl threads tutorial 旧式 Perl スレッドチュートリアル perlport Perl portability guide Perl 可搬性ガイド perllocale Perl locale support Perl ロケールサポート perluniintro Perl Unicode introduction Perl ユニコード導入 perlunicode Perl Unicode support Perl ユニコードサポート perlebcdic Considerations for running Perl on EBCDIC platforms EBCDICプラットフォームに対する考慮 perlsec Perl security Perl セキュリティ perlmod Perl modules: how they work Perl モジュール: どの様に機能するか perlmodlib Perl modules: how to write and use Perl モジュール: 書き方と使い方 perlmodstyle Perl modules: how to write modules with style Perl モジュール: 定型 perlmodinstall Perl modules: how to install from CPAN Perl モジュール: CPANからのインストール方法 perlnewmod Perl modules: preparing a new module for distribution Perl モジュール: 配布の準備 perlutil utilities packaged with the Perl distribution Perl 配布物と一緒に含まれるユーティリティ perlcompile Perl compiler suite intro Perl コンパイラスイートイントロ perlfilter Perl source filters Perl ソースフィルタ perlglossary Perl Glossary Perl 用語集 =head2 Internals and C Language Interface perlembed Perl ways to embed perl in your C or C++ application C 又は C++ アプリケーションへ perl を内蔵する方法 perldebguts Perl debugging guts and tips Perl デバッグガッツとティップス perlxstut Perl XS tutorial Perl XS チュートリアル perlxs Perl XS application programming interface Perl XS アプリケーションプログラミングインターフェース perlclib Internal replacements for standard C library functions C ライブラリ関数の内部変換 perlguts Perl internal functions for those doing extensions これらを拡張するための内部関数 perlcall Perl calling conventions from C C 言語からの Perl 呼び出し規約 perlapi Perl API listing (autogenerated) Perl API 一覧 (自動生成) perlintern Perl internal functions (autogenerated) Perl 内部関数 (自動生成) perliol C API for Perl's implementation of IO in Layers Perl での IO レイヤ実装のための C API perlapio Perl internal IO abstraction interface Perl 内部 IO 抽象化インターフェース perlhack Perl hackers guide Perl ハッカーガイド =head2 Miscellaneous perlbook Perl book information perltodo Perl things to do perldoc Look up Perl documentation in Pod format perlhist Perl history records perldelta Perl changes since previous version perl587delta Perl changes in version 5.8.7 perl586delta Perl changes in version 5.8.6 perl585delta Perl changes in version 5.8.5 perl584delta Perl changes in version 5.8.4 perl583delta Perl changes in version 5.8.3 perl582delta Perl changes in version 5.8.2 perl581delta Perl changes in version 5.8.1 perl58delta Perl changes in version 5.8.0 perl573delta Perl changes in version 5.7.3 perl572delta Perl changes in version 5.7.2 perl571delta Perl changes in version 5.7.1 perl570delta Perl changes in version 5.7.0 perl561delta Perl changes in version 5.6.1 perl56delta Perl changes in version 5.6 perl5005delta Perl changes in version 5.005 perl5004delta Perl changes in version 5.004 perlartistic Perl Artistic License perlgpl GNU General Public License =head2 Language-Specific perlcn Perl for Simplified Chinese (in EUC-CN) perljp Perl for Japanese (in EUC-JP) perlko Perl for Korean (in EUC-KR) perltw Perl for Traditional Chinese (in Big5) =head2 Platform-Specific perlaix Perl notes for AIX perlamiga Perl notes for AmigaOS perlapollo Perl notes for Apollo DomainOS perlbeos Perl notes for BeOS perlbs2000 Perl notes for POSIX-BC BS2000 perlce Perl notes for WinCE perlcygwin Perl notes for Cygwin perldgux Perl notes for DG/UX perldos Perl notes for DOS perlepoc Perl notes for EPOC perlfreebsd Perl notes for FreeBSD perlhpux Perl notes for HP-UX perlhurd Perl notes for Hurd perlirix Perl notes for Irix perllinux Perl notes for Linux perlmachten Perl notes for Power MachTen perlmacos Perl notes for Mac OS (Classic) perlmacosx Perl notes for Mac OS X perlmint Perl notes for MiNT perlmpeix Perl notes for MPE/iX perlnetware Perl notes for NetWare perlopenbsd Perl notes for OpenBSD perlos2 Perl notes for OS/2 perlos390 Perl notes for OS/390 perlos400 Perl notes for OS/400 perlplan9 Perl notes for Plan 9 perlqnx Perl notes for QNX perlsolaris Perl notes for Solaris perltru64 Perl notes for Tru64 perluts Perl notes for UTS perlvmesa Perl notes for VM/ESA perlvms Perl notes for VMS perlvos Perl notes for Stratus VOS perlwin32 Perl notes for Windows By default, the manpages listed above are installed in the F directory. Extensive additional documentation for Perl modules is available. The default configuration for perl will place this additional documentation in the F directory (or else in the F 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 F and F, you need only to add that stem (F) 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 F 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 B<-w> switch first. It will often point out exactly where the trouble is. =head1 DESCRIPTION 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, B, B, and B, so people familiar with those languages should have little difficulty with it. (Language historians will also note some vestiges of B, Pascal, and even BASIC-PLUS.) Expression syntax corresponds 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 (sometimes called "associative arrays") grow as necessary to prevent degraded performance. Perl can use sophisticated pattern matching techniques to scan large amounts of data 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 that prevents many stupid security holes. If you have a problem that would ordinarily use B or B or B, 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 B and B scripts into Perl scripts. But wait, there's more... Begun in 1993 (see L), Perl version 5 is nearly a complete rewrite that provides the following additional benefits: =over 4 =item * modularity and reusability using innumerable modules Described in L, L, and L. =item * embeddable and extensible Described in L, L, L, L, L, and L. =item * roll-your-own magic variables (including multiple simultaneous DBM implementations) Described in L and L. =item * subroutines can now be overridden, autoloaded, and prototyped Described in L. =item * arbitrarily nested data structures and anonymous functions Described in L, L, L, and L. =item * object-oriented programming Described in L, L, L, L, and L. =item * support for light-weight processes (threads) Described in L and L. =item * support for Unicode, internationalization, and localization Described in L, L and L. =item * lexical scoping Described in L. =item * regular expression enhancements Described in L, with additional examples in L. =item * enhanced debugger and interactive Perl environment, with integrated editor support Described in L, L and L. =item * POSIX 1003.1 compliant library Described in L. =back Okay, that's I enough hype. =head1 AVAILABILITY Perl is available for most operating systems, including virtually all Unix-like platforms. See L for a listing. =head1 ENVIRONMENT See L. =head1 AUTHOR Larry Wall , with the help of oodles of other folks. If your Perl success stories and testimonials may be of help to others who wish to advocate the use of Perl in their applications, or if you wish to simply express your gratitude to Larry and the Perl developers, please write to perl-thanks@perl.org . =head1 FILES "@INC" locations of perl libraries =head1 SEE ALSO a2p awk to perl translator s2p sed to perl translator http://www.perl.org/ the Perl homepage http://www.perl.com/ Perl articles (O'Reilly) http://www.cpan.org/ the Comprehensive Perl Archive http://www.pm.org/ the Perl Mongers =head1 DIAGNOSTICS The C pragma (and the B<-w> switch) produces some lovely diagnostics. See L for explanations of all Perl's diagnostics. The C pragma automatically turns Perl's normally terse warnings and errors into these longer forms. Compilation errors will tell you the line number of the error, with an indication of the next token or token type that was to be examined. (In a script passed to Perl via B<-e> switches, each B<-e> is counted as one line.) Setuid scripts have additional constraints that can produce error messages such as "Insecure dependency". See L. Did we mention that you should definitely consider using the B<-w> switch? =head1 BUGS The B<-w> switch is not mandatory. Perl is at the mercy of your machine's definitions of various operations such as type casting, atof(), and floating-point output with sprintf(). If your stdio requires a seek or eof between reads and writes on a particular stream, so does Perl. (This doesn't apply to sysread() and syswrite().) While none of the built-in data types have any arbitrary size limits (apart from memory size), there are still a few arbitrary limits: a given variable name may not be longer than 251 characters. Line numbers displayed by diagnostics are internally stored as short integers, so they are limited to a maximum of 65535 (higher numbers usually being affected by wraparound). You may mail your bug reports (be sure to include full configuration information as output by the myconfig program in the perl source tree, or by C) to perlbug@perl.org . If you've succeeded in compiling perl, the B script in the F subdirectory can be used to help mail in a bug report. Perl actually stands for Pathologically Eclectic Rubbish Lister, but don't tell anyone I said that. =head1 NOTES The Perl motto is "There's more than one way to do it." Divining how many more is left as an exercise to the reader. The three principal virtues of a programmer are Laziness, Impatience, and Hubris. See the Camel Book for why.