=head1 SYNOPSIS
-B<perl> S<[ B<-sTuU> ]>
- S<[ B<-hv> ] [ B<-V>[:I<configvar>] ]>
- S<[ B<-cw> ] [ B<-d>[:I<debugger>] ] [ B<-D>[I<number/list>] ]>
- S<[ B<-pna> ] [ B<-F>I<pattern> ] [ B<-l>[I<octal>] ] [ B<-0>[I<octal>] ]>
- S<[ B<-I>I<dir> ] [ B<-m>[B<->]I<module> ] [ B<-M>[B<->]I<'module...'> ]>
- S<[ B<-P> ]>
- S<[ B<-S> ]>
- S<[ B<-x>[I<dir>] ]>
- S<[ B<-i>[I<extension>] ]>
- S<[ B<-e> I<'command'> ] [ B<--> ] [ I<programfile> ] [ I<argument> ]...>
-
-For ease of access, the Perl manual has been split up into a number
-of sections:
+B<perl> S<[ B<-sTuU> ]> S<[ B<-hv> ] [ B<-V>[:I<configvar>] ]>
+ S<[ B<-cw> ] [ B<-d>[:I<debugger>] ] [ B<-D>[I<number/list>] ]>
+ S<[ B<-pna> ] [ B<-F>I<pattern> ] [ B<-l>[I<octal>] ] [ B<-0>[I<octal>] ]>
+ S<[ B<-I>I<dir> ] [ B<-m>[B<->]I<module> ] [ B<-M>[B<->]I<'module...'> ]>
+ S<[ B<-P> ]> S<[ B<-S> ]> S<[ B<-x>[I<dir>] ]>
+ S<[ B<-i>[I<extension>] ]> S<[ B<-e> I<'command'> ]
+ [ B<--> ] [ I<programfile> ] [ I<argument> ]...>
+
+For ease of access, the Perl manual has been split up into several
+sections:
perl Perl overview (this section)
perldelta Perl changes since previous version
perlform Perl formats
perllocale Perl locale support
- perlref Perl references
perlreftut Perl references short introduction
+ perlref Perl references, the rest of the story
perldsc Perl data structures intro
- perllol Perl data structures: lists of lists
- perltoot Perl OO tutorial
+ perllol Perl data structures: arrays of arrays
+ perltoot Perl OO tutorial, part 1
+ perltootc Perl OO tutorial, part 2
perlobj Perl objects
perltie Perl objects hidden behind simple variables
perlbot Perl OO tricks and examples
perlipc Perl interprocess communication
+ perlfork Perl fork() information
perlthrtut Perl threads tutorial
+ perldbmfilter Perl DBM Filters
+ perlcompile Perl compiler suite intro
perldebug Perl debugging
perldiag Perl diagnostic messages
perlsec Perl security
perlcall Perl calling conventions from C
perltodo Perl things to do
+ perlhack Perl hackers guide
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
+By default, the manpages listed above are installed in the
F</usr/local/man/> directory.
Extensive additional documentation for Perl modules is available. The
features of C, B<sed>, B<awk>, and B<sh>, so people familiar with
those languages should have little difficulty with it. (Language
historians will also note some vestiges of B<csh>, Pascal, and even
-BASIC-PLUS.) Expression syntax corresponds quite closely to C
+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 very quickly. Although optimized for
+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 which prevents many stupid
+through a dataflow tracing mechanism that prevents many stupid
security holes.
If you have a problem that would ordinarily use B<sed> or B<awk> or
But wait, there's more...
-Perl version 5 is nearly a complete rewrite, and provides
-the following additional benefits:
-
-=over 5
-
-=item * Many usability enhancements
+Begun in 1993 (see L<perlhist>), Perl version 5 is nearly a complete
+rewrite that provides the following additional benefits:
-It is now possible to write much more readable Perl code (even within
-regular expressions). Formerly cryptic variable names can be replaced
-by mnemonic identifiers. Error messages are more informative, and the
-optional warnings will catch many of the mistakes a novice might make.
-This cannot be stressed enough. Whenever you get mysterious behavior,
-try the B<-w> switch!!! Whenever you don't get mysterious behavior,
-try using B<-w> anyway.
+=over
-=item * Simplified grammar
+=item * modularity and reusability using innumerable modules
-The new yacc grammar is one half the size of the old one. Many of the
-arbitrary grammar rules have been regularized. The number of reserved
-words has been cut by 2/3. Despite this, nearly all old Perl scripts
-will continue to work unchanged.
+Described in L<perlmod>, L<perlmodlib>, and L<perlmodinstall>.
-=item * Lexical scoping
+=item * embeddable and extensible
-Perl variables may now be declared within a lexical scope, like "auto"
-variables in C. Not only is this more efficient, but it contributes
-to better privacy for "programming in the large". Anonymous
-subroutines exhibit deep binding of lexical variables (closures).
+Described in L<perlembed>, L<perlxstut>, L<perlxs>, L<perlcall>,
+L<perlguts>, and L<xsubpp>.
-=item * Arbitrarily nested data structures
+=item * roll-your-own magic variables (including multiple simultaneous DBM implementations)
-Any scalar value, including any array element, may now contain a
-reference to any other variable or subroutine. You can easily create
-anonymous variables and subroutines. Perl manages your reference
-counts for you.
+Described in L<perltie> and L<AnyDBM_File>.
-=item * Modularity and reusability
+=item * subroutines can now be overridden, autoloaded, and prototyped
-The Perl library is now defined in terms of modules which can be easily
-shared among various packages. A package may choose to import all or a
-portion of a module's published interface. Pragmas (that is, compiler
-directives) are defined and used by the same mechanism.
+Described in L<perlsub>.
-=item * Object-oriented programming
+=item * arbitrarily nested data structures and anonymous functions
-A package can function as a class. Dynamic multiple inheritance and
-virtual methods are supported in a straightforward manner and with very
-little new syntax. Filehandles may now be treated as objects.
+Described in L<perlreftut>, L<perlref>, L<perldsc>, and L<perllol>.
-=item * Embeddable and Extensible
+=item * object-oriented programming
-Perl may now be embedded easily in your C or C++ application, and can
-either call or be called by your routines through a documented
-interface. The XS preprocessor is provided to make it easy to glue
-your C or C++ routines into Perl. Dynamic loading of modules is
-supported, and Perl itself can be made into a dynamic library.
+Described in L<perlobj>, L<perltoot>, and L<perlbot>.
-=item * POSIX compliant
+=item * compilability into C code or Perl bytecode
-A major new module is the POSIX module, which provides access to all
-available POSIX routines and definitions, via object classes where
-appropriate.
+Described in L<B> and L<B::Bytecode>.
-=item * Package constructors and destructors
+=item * support for light-weight processes (threads)
-The new BEGIN and END blocks provide means to capture control as
-a package is being compiled, and after the program exits. As a
-degenerate case they work just like awk's BEGIN and END when you
-use the B<-p> or B<-n> switches.
+Described in L<perlthrtut> and L<Thread>.
-=item * Multiple simultaneous DBM implementations
+=item * support for internationalization, localization, and Unicode
-A Perl program may now access DBM, NDBM, SDBM, GDBM, and Berkeley DB
-files from the same script simultaneously. In fact, the old dbmopen
-interface has been generalized to allow any variable to be tied
-to an object class which defines its access methods.
+Described in L<perllocale> and L<utf8>.
-=item * Subroutine definitions may now be autoloaded
+=item * lexical scoping
-In fact, the AUTOLOAD mechanism also allows you to define any arbitrary
-semantics for undefined subroutine calls. It's not for just autoloading.
+Described in L<perlsub>.
-=item * Regular expression enhancements
+=item * regular expression enhancements
-You can now specify nongreedy quantifiers. You can now do grouping
-without creating a backreference. You can now write regular expressions
-with embedded whitespace and comments for readability. A consistent
-extensibility mechanism has been added that is upwardly compatible with
-all old regular expressions.
+Described in L<perlre>, with additional examples in L<perlop>.
-=item * Innumerable Unbundled Modules
+=item * enhanced debugger and interactive Perl environment, with integrated editor support
-The Comprehensive Perl Archive Network described in L<perlmodlib>
-contains hundreds of plug-and-play modules full of reusable code.
-See F<http://www.perl.com/CPAN> for a site near you.
+Described in L<perldebug>.
-=item * Compilability
+=item * POSIX 1003.1 compliant library
-While not yet in full production mode, a working perl-to-C compiler
-does exist. It can generate portable byte code, simple C, or
-optimized C code.
+Described in L<POSIX>.
=back
=head1 AVAILABILITY
-Perl is available for the vast majority of operating system platforms,
-including most Unix-like platforms. The following situation is as of
-February 1999 and Perl 5.005_03.
+Perl is available for most operating systems, including virtually
+all Unix-like platforms.
-The following platforms are able to build Perl from the standard
-source code distribution available at
-F<http://www.perl.com/CPAN/src/index.html>
+As of May 1999, the following platforms are able to build Perl
+from the standard source code distribution available at
+http://www.perl.com/CPAN/src/index.html
AIX Linux SCO ODT/OSR
A/UX MachTen Solaris
1) in DOS mode either the DOS or OS/2 ports can be used
2) formerly known as MVS
3) formerly known as Digital UNIX and before that DEC OSF/1
- 4) compilers: Borland, Cygwin32, Mingw32 EGCS/GCC, VC++
+ 4) compilers: Borland, Cygwin, Mingw32 EGCS/GCC, VC++
-The following platforms have been known to build Perl from the source
-but for the Perl release 5.005_03 we haven't been able to verify them,
-either because the hardware/software platforms are rather rare or
-because we don't have an active champion on these platforms, or both.
+The following platforms have been known to build Perl from source,
+but we haven't been able to verify their status for the current release,
+either because the hardware/software platforms are rare or
+because we don't have an active champion on these platforms--or both.
3b1 FPS Plan 9
AmigaOS GENIX PowerUX
EP/IX Opus Unisys Dynix
ESIX Unixware
-The following platforms are planned to be supported in the standard
-source code distribution of the Perl release 5.006 but are not
-supported in the Perl release 5.005_03:
+Support for the following platforms is planned for the next major
+Perl release.
BS2000
Netware
VM/ESA
The following platforms have their own source code distributions and
-binaries available via F<http://www.perl.com/CPAN/ports/index.html>.
+binaries available via http://www.perl.com/CPAN/ports/index.html.
Perl release
Tandem Guardian 5.004
The following platforms have only binaries available via
-F<http://www.perl.com/CPAN/ports/index.html>.
+http://www.perl.com/CPAN/ports/index.html.
Perl release
=head1 AUTHOR
-Larry Wall <F<larry@wall.org>>, with the help of oodles of other folks.
+Larry Wall <larry@wall.org>, 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 <F<perl-thanks@perl.org>>.
+Perl developers, please write to perl-thanks@perl.org .
=head1 FILES
=head1 SEE ALSO
a2p awk to perl translator
-
s2p sed to perl translator
+ http://www.perl.com/ the Perl Home Page
+ http://www.perl.com/CPAN the Comphrehensive Perl Archive
+
=head1 DIAGNOSTICS
The B<-w> switch produces some lovely diagnostics.
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 the case of a script passed to Perl via B<-e> switches, each
+(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
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<perl -V>) to <F<perlbug@perl.com>>.
-If you've succeeded in compiling perl, the perlbug script in the utils/
-subdirectory can be used to help mail in a bug report.
+information as output by the myconfig program in the perl source
+tree, or by C<perl -V>) to perlbug@perl.com . If you've succeeded
+in compiling perl, the perlbug script in the utils/ 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.
https://perl5.git.perl.org / perl5.git / blobdiff