[OpenSPARC-T2-DV] / tools / perl-5.8.0 / lib / 5.8.0 / pod / perl.pod

=head1 NAME

perl - Practical Extraction and Report Language

=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> ]...>

If you're new to Perl, you should start with L<perlintro>, 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)
    perlintro		Perl introduction for beginners
    perltoc		Perl documentation table of contents

=head2 Tutorials

    perlreftut		Perl references short introduction
    perldsc		Perl data structures intro
    perllol		Perl data structures: arrays of arrays

    perlrequick		Perl regular expressions quick start
    perlretut		Perl regular expressions tutorial

    perlboot		Perl OO tutorial for beginners
    perltoot		Perl OO tutorial, part 1
    perltooc		Perl OO tutorial, part 2
    perlbot		Perl OO tricks and examples

    perlstyle		Perl style guide

    perltrap		Perl traps for the unwary
    perldebtut		Perl debugging tutorial

    perlfaq		Perl frequently asked questions
      perlfaq1		General Questions About Perl
      perlfaq2		Obtaining and Learning about Perl
      perlfaq3		Programming Tools
      perlfaq4		Data Manipulation
      perlfaq5		Files and Formats
      perlfaq6		Regexes
      perlfaq7		Perl Language Issues
      perlfaq8		System Interaction
      perlfaq9		Networking

=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
    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
      perlothrtut	  Old Perl threads tutorial

    perlport		Perl portability guide
    perllocale		Perl locale support
    perluniintro	Perl Unicode introduction
    perlunicode		Perl Unicode support
    perlebcdic		Considerations for running Perl on EBCDIC platforms

    perlsec		Perl security

    perlmod		Perl modules: how they work
    perlmodlib		Perl modules: how to write and use
    perlmodstyle	Perl modules: how to write modules with style
    perlmodinstall	Perl modules: how to install from CPAN
    perlnewmod		Perl modules: preparing a new module for distribution

    perlutil		utilities packaged with the Perl distribution

    perlcompile		Perl compiler suite intro

    perlfilter		Perl source filters

=head2 Internals and C Language Interface

    perlembed		Perl ways to embed perl in your C or C++ application
    perldebguts		Perl debugging guts and tips
    perlxstut		Perl XS tutorial
    perlxs		Perl XS application programming interface
    perlclib		Internal replacements for standard C library functions
    perlguts		Perl internal functions for those doing extensions
    perlcall		Perl calling conventions from C

    perlapi		Perl API listing (autogenerated)
    perlintern		Perl internal functions (autogenerated)
    perliol		C API for Perl's implementation of IO in Layers
    perlapio		Perl internal IO abstraction interface

    perlhack		Perl hackers guide

=head2 Miscellaneous

    perlbook		Perl book information
    perltodo		Perl things to do

    perlhist		Perl history records
    perldelta		Perl changes since previous version
    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

=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
    perlmachten		Perl notes for Power MachTen
    perlmacos		Perl notes for Mac OS (Classic)
    perlmint		Perl notes for MiNT
    perlmpeix		Perl notes for MPE/iX
    perlnetware		Perl notes for NetWare
    perlos2		Perl notes for OS/2
    perlos390		Perl notes for OS/390
    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</usr/local/man/> directory.  

Extensive additional documentation for Perl modules is available.  The
default configuration for perl will place this additional documentation
in the F</usr/local/lib/perl5/man> directory (or else in the F<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 F</usr/local/man/man1>
and F</usr/local/man/man3>, you need only to add that stem
(F</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 F<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 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<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 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<sed> or B<awk> or
B<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 B<sed> and B<awk>
scripts into Perl scripts.

But wait, there's more...

Begun in 1993 (see L<perlhist>), 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<perlmod>, L<perlmodlib>, and L<perlmodinstall>.

=item *

embeddable and extensible 

Described in L<perlembed>, L<perlxstut>, L<perlxs>, L<perlcall>,
L<perlguts>, and L<xsubpp>.

=item *

roll-your-own magic variables (including multiple simultaneous DBM implementations)

Described in L<perltie> and L<AnyDBM_File>.

=item *

subroutines can now be overridden, autoloaded, and prototyped

Described in L<perlsub>.

=item *

arbitrarily nested data structures and anonymous functions

Described in L<perlreftut>, L<perlref>, L<perldsc>, and L<perllol>.

=item *

object-oriented programming

Described in L<perlobj>, L<perlboot>, L<perltoot>, L<perltooc>,
and L<perlbot>.

=item *

compilability into C code or Perl bytecode

Described in L<B> and L<B::Bytecode>.

=item *

support for light-weight processes (threads)

Described in L<perlthrtut> and L<Thread>.

=item *

support for internationalization, localization, and Unicode 

Described in L<perllocale> and L<utf8>.

=item *

lexical scoping

Described in L<perlsub>.

=item *

regular expression enhancements

Described in L<perlre>, with additional examples in L<perlop>.

=item *

enhanced debugger and interactive Perl environment,
with integrated editor support

Described in L<perldebtut>, L<perldebug> and L<perldebguts>.

=item *

POSIX 1003.1 compliant library

Described in L<POSIX>.

=back

Okay, that's I<definitely> enough hype.

=head1 AVAILABILITY

Perl is available for most operating systems, including virtually
all Unix-like platforms.  See L<perlport/"Supported Platforms">
for a listing.

=head1 ENVIRONMENT

See L<perlrun>.

=head1 AUTHOR

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 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.com/       the Perl Home Page
 http://www.cpan.org/       the Comprehensive Perl Archive
 http://www.perl.org/       Perl Mongers (Perl user groups)

=head1 DIAGNOSTICS

The C<use warnings> pragma (and the B<-w> switch) produces some 
lovely diagnostics.

See L<perldiag> for explanations of all Perl's diagnostics.  The C<use
diagnostics> 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<perlsec>.

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<perl -V>) to perlbug@perl.org .  If you've succeeded
in compiling perl, the B<perlbug> script in the F<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.

=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.
Commit	Line	Data
86530b38 AT	1	=head1 NAME
	2
	3	perl - Practical Extraction and Report Language
	4
	5	=head1 SYNOPSIS
	6
	7	B<perl> S<[ B<-sTuU> ]> S<[ B<-hv> ] [ B<-V>[:I<configvar>] ]>
	8	S<[ B<-cw> ] [ B<-d>[:I<debugger>] ] [ B<-D>[I<number/list>] ]>
	9	S<[ B<-pna> ] [ B<-F>I<pattern> ] [ B<-l>[I<octal>] ] [ B<-0>[I<octal>] ]>
	10	S<[ B<-I>I<dir> ] [ B<-m>[B<->]I<module> ] [ B<-M>[B<->]I<'module...'> ]>
	11	S<[ B<-P> ]> S<[ B<-S> ]> S<[ B<-x>[I<dir>] ]>
	12	S<[ B<-i>[I<extension>] ]> S<[ B<-e> I<'command'> ]
	13	[ B<--> ] [ I<programfile> ] [ I<argument> ]...>
	14
	15	If you're new to Perl, you should start with L<perlintro>, which is a
	16	general intro for beginners and provides some background to help you
	17	navigate the rest of Perl's extensive documentation.
	18
	19	For ease of access, the Perl manual has been split up into several sections.
	20
	21	=head2 Overview
	22
	23	perl Perl overview (this section)
	24	perlintro Perl introduction for beginners
	25	perltoc Perl documentation table of contents
	26
	27	=head2 Tutorials
	28
	29	perlreftut Perl references short introduction
	30	perldsc Perl data structures intro
	31	perllol Perl data structures: arrays of arrays
	32
	33	perlrequick Perl regular expressions quick start
	34	perlretut Perl regular expressions tutorial
	35
	36	perlboot Perl OO tutorial for beginners
	37	perltoot Perl OO tutorial, part 1
	38	perltooc Perl OO tutorial, part 2
	39	perlbot Perl OO tricks and examples
	40
	41	perlstyle Perl style guide
	42
	43	perltrap Perl traps for the unwary
	44	perldebtut Perl debugging tutorial
	45
	46	perlfaq Perl frequently asked questions
	47	perlfaq1 General Questions About Perl
	48	perlfaq2 Obtaining and Learning about Perl
	49	perlfaq3 Programming Tools
	50	perlfaq4 Data Manipulation
	51	perlfaq5 Files and Formats
	52	perlfaq6 Regexes
	53	perlfaq7 Perl Language Issues
	54	perlfaq8 System Interaction
	55	perlfaq9 Networking
	56
	57	=head2 Reference Manual
	58
	59	perlsyn Perl syntax
	60	perldata Perl data structures
	61	perlop Perl operators and precedence
	62	perlsub Perl subroutines
	63	perlfunc Perl built-in functions
	64	perlopentut Perl open() tutorial
65	perlpacktut Perl pack() and unpack() tutorial
66	perlpod Perl plain old documentation
67	perlpodspec Perl plain old documentation format specification
68	perlrun Perl execution and options
69	perldiag Perl diagnostic messages
70	perllexwarn Perl warnings and their control
71	perldebug Perl debugging
72	perlvar Perl predefined variables
73	perlre Perl regular expressions, the rest of the story
74	perlref Perl references, the rest of the story
75	perlform Perl formats
76	perlobj Perl objects
77	perltie Perl objects hidden behind simple variables
78	perldbmfilter Perl DBM filters
79
80	perlipc Perl interprocess communication
81	perlfork Perl fork() information
82	perlnumber Perl number semantics
83
84	perlthrtut Perl threads tutorial
85	perlothrtut Old Perl threads tutorial
86
87	perlport Perl portability guide
88	perllocale Perl locale support
89	perluniintro Perl Unicode introduction
90	perlunicode Perl Unicode support
91	perlebcdic Considerations for running Perl on EBCDIC platforms
92
93	perlsec Perl security
94
95	perlmod Perl modules: how they work
96	perlmodlib Perl modules: how to write and use
97	perlmodstyle Perl modules: how to write modules with style
98	perlmodinstall Perl modules: how to install from CPAN
99	perlnewmod Perl modules: preparing a new module for distribution
100
101	perlutil utilities packaged with the Perl distribution
102
103	perlcompile Perl compiler suite intro
104
105	perlfilter Perl source filters
106
107	=head2 Internals and C Language Interface
108
109	perlembed Perl ways to embed perl in your C or C++ application
110	perldebguts Perl debugging guts and tips
111	perlxstut Perl XS tutorial
112	perlxs Perl XS application programming interface
113	perlclib Internal replacements for standard C library functions
114	perlguts Perl internal functions for those doing extensions
115	perlcall Perl calling conventions from C
116
117	perlapi Perl API listing (autogenerated)
118	perlintern Perl internal functions (autogenerated)
119	perliol C API for Perl's implementation of IO in Layers
120	perlapio Perl internal IO abstraction interface
121
122	perlhack Perl hackers guide
123
124	=head2 Miscellaneous
125
126	perlbook Perl book information
127	perltodo Perl things to do
128
129	perlhist Perl history records
130	perldelta Perl changes since previous version
131	perl572delta Perl changes in version 5.7.2
132	perl571delta Perl changes in version 5.7.1
133	perl570delta Perl changes in version 5.7.0
134	perl561delta Perl changes in version 5.6.1
135	perl56delta Perl changes in version 5.6
136	perl5005delta Perl changes in version 5.005
137	perl5004delta Perl changes in version 5.004
138
139	=head2 Language-Specific
140
141	perlcn Perl for Simplified Chinese (in EUC-CN)
142	perljp Perl for Japanese (in EUC-JP)
143	perlko Perl for Korean (in EUC-KR)
144	perltw Perl for Traditional Chinese (in Big5)
145
146	=head2 Platform-Specific
147
148	perlaix Perl notes for AIX
149	perlamiga Perl notes for AmigaOS
150	perlapollo Perl notes for Apollo DomainOS
151	perlbeos Perl notes for BeOS
152	perlbs2000 Perl notes for POSIX-BC BS2000
153	perlce Perl notes for WinCE
154	perlcygwin Perl notes for Cygwin
155	perldgux Perl notes for DG/UX
156	perldos Perl notes for DOS
157	perlepoc Perl notes for EPOC
158	perlfreebsd Perl notes for FreeBSD
159	perlhpux Perl notes for HP-UX
160	perlhurd Perl notes for Hurd
161	perlirix Perl notes for Irix
162	perlmachten Perl notes for Power MachTen
163	perlmacos Perl notes for Mac OS (Classic)
164	perlmint Perl notes for MiNT
165	perlmpeix Perl notes for MPE/iX
166	perlnetware Perl notes for NetWare
167	perlos2 Perl notes for OS/2
168	perlos390 Perl notes for OS/390
169	perlplan9 Perl notes for Plan 9
170	perlqnx Perl notes for QNX
171	perlsolaris Perl notes for Solaris
172	perltru64 Perl notes for Tru64
173	perluts Perl notes for UTS
174	perlvmesa Perl notes for VM/ESA
175	perlvms Perl notes for VMS
176	perlvos Perl notes for Stratus VOS
177	perlwin32 Perl notes for Windows
178
179
180	By default, the manpages listed above are installed in the
181	F</usr/local/man/> directory.
182
183	Extensive additional documentation for Perl modules is available. The
184	default configuration for perl will place this additional documentation
185	in the F</usr/local/lib/perl5/man> directory (or else in the F<man>
186	subdirectory of the Perl library directory). Some of this additional
187	documentation is distributed standard with Perl, but you'll also find
188	documentation for third-party modules there.
189
190	You should be able to view Perl's documentation with your man(1)
191	program by including the proper directories in the appropriate start-up
192	files, or in the MANPATH environment variable. To find out where the
193	configuration has installed the manpages, type:
194
195	perl -V:man.dir
196
197	If the directories have a common stem, such as F</usr/local/man/man1>
198	and F</usr/local/man/man3>, you need only to add that stem
199	(F</usr/local/man>) to your man(1) configuration files or your MANPATH
200	environment variable. If they do not share a stem, you'll have to add
201	both stems.
202
203	If that doesn't work for some reason, you can still use the
204	supplied F<perldoc> script to view module information. You might
205	also look into getting a replacement man program.
206
207	If something strange has gone wrong with your program and you're not
208	sure where you should look for help, try the B<-w> switch first. It
209	will often point out exactly where the trouble is.
210
211	=head1 DESCRIPTION
212
213	Perl is a language optimized for scanning arbitrary
214	text files, extracting information from those text files, and printing
215	reports based on that information. It's also a good language for many
216	system management tasks. The language is intended to be practical
217	(easy to use, efficient, complete) rather than beautiful (tiny,
218	elegant, minimal).
219
220	Perl combines (in the author's opinion, anyway) some of the best
221	features of C, B<sed>, B<awk>, and B<sh>, so people familiar with
222	those languages should have little difficulty with it. (Language
223	historians will also note some vestiges of B<csh>, Pascal, and even
224	BASIC-PLUS.) Expression syntax corresponds closely to C
225	expression syntax. Unlike most Unix utilities, Perl does not
226	arbitrarily limit the size of your data--if you've got the memory,
227	Perl can slurp in your whole file as a single string. Recursion is of
228	unlimited depth. And the tables used by hashes (sometimes called
229	"associative arrays") grow as necessary to prevent degraded
230	performance. Perl can use sophisticated pattern matching techniques to
231	scan large amounts of data quickly. Although optimized for
232	scanning text, Perl can also deal with binary data, and can make dbm
233	files look like hashes. Setuid Perl scripts are safer than C programs
234	through a dataflow tracing mechanism that prevents many stupid
235	security holes.
236
237	If you have a problem that would ordinarily use B<sed> or B<awk> or
238	B<sh>, but it exceeds their capabilities or must run a little faster,
239	and you don't want to write the silly thing in C, then Perl may be for
240	you. There are also translators to turn your B<sed> and B<awk>
241	scripts into Perl scripts.
242
243	But wait, there's more...
244
245	Begun in 1993 (see L<perlhist>), Perl version 5 is nearly a complete
246	rewrite that provides the following additional benefits:
247
248	=over 4
249
250	=item *
251
252	modularity and reusability using innumerable modules
253
254	Described in L<perlmod>, L<perlmodlib>, and L<perlmodinstall>.
255
256	=item *
257
258	embeddable and extensible
259
260	Described in L<perlembed>, L<perlxstut>, L<perlxs>, L<perlcall>,
261	L<perlguts>, and L<xsubpp>.
262
263	=item *
264
265	roll-your-own magic variables (including multiple simultaneous DBM implementations)
266
267	Described in L<perltie> and L<AnyDBM_File>.
268
269	=item *
270
271	subroutines can now be overridden, autoloaded, and prototyped
272
273	Described in L<perlsub>.
274
275	=item *
276
277	arbitrarily nested data structures and anonymous functions
278
279	Described in L<perlreftut>, L<perlref>, L<perldsc>, and L<perllol>.
280
281	=item *
282
283	object-oriented programming
284
285	Described in L<perlobj>, L<perlboot>, L<perltoot>, L<perltooc>,
286	and L<perlbot>.
287
288	=item *
289
290	compilability into C code or Perl bytecode
291
292	Described in L<B> and L<B::Bytecode>.
293
294	=item *
295
296	support for light-weight processes (threads)
297
298	Described in L<perlthrtut> and L<Thread>.
299
300	=item *
301
302	support for internationalization, localization, and Unicode
303
304	Described in L<perllocale> and L<utf8>.
305
306	=item *
307
308	lexical scoping
309
310	Described in L<perlsub>.
311
312	=item *
313
314	regular expression enhancements
315
316	Described in L<perlre>, with additional examples in L<perlop>.
317
318	=item *
319
320	enhanced debugger and interactive Perl environment,
321	with integrated editor support
322
323	Described in L<perldebtut>, L<perldebug> and L<perldebguts>.
324
325	=item *
326
327	POSIX 1003.1 compliant library
328
329	Described in L<POSIX>.
330
331	=back
332
333	Okay, that's I<definitely> enough hype.
334
335	=head1 AVAILABILITY
336
337	Perl is available for most operating systems, including virtually
338	all Unix-like platforms. See L<perlport/"Supported Platforms">
339	for a listing.
340
341	=head1 ENVIRONMENT
342
343	See L<perlrun>.
344
345	=head1 AUTHOR
346
347	Larry Wall <larry@wall.org>, with the help of oodles of other folks.
348
349	If your Perl success stories and testimonials may be of help to others
350	who wish to advocate the use of Perl in their applications,
351	or if you wish to simply express your gratitude to Larry and the
352	Perl developers, please write to perl-thanks@perl.org .
353
354	=head1 FILES
355
356	"@INC" locations of perl libraries
357
358	=head1 SEE ALSO
359
360	a2p awk to perl translator
361	s2p sed to perl translator
362
363	http://www.perl.com/ the Perl Home Page
364	http://www.cpan.org/ the Comprehensive Perl Archive
365	http://www.perl.org/ Perl Mongers (Perl user groups)
366
367	=head1 DIAGNOSTICS
368
369	The C<use warnings> pragma (and the B<-w> switch) produces some
370	lovely diagnostics.
371
372	See L<perldiag> for explanations of all Perl's diagnostics. The C<use
373	diagnostics> pragma automatically turns Perl's normally terse warnings
374	and errors into these longer forms.
375
376	Compilation errors will tell you the line number of the error, with an
377	indication of the next token or token type that was to be examined.
378	(In a script passed to Perl via B<-e> switches, each
379	B<-e> is counted as one line.)
380
381	Setuid scripts have additional constraints that can produce error
382	messages such as "Insecure dependency". See L<perlsec>.
383
384	Did we mention that you should definitely consider using the B<-w>
385	switch?
386
387	=head1 BUGS
388
389	The B<-w> switch is not mandatory.
390
391	Perl is at the mercy of your machine's definitions of various
392	operations such as type casting, atof(), and floating-point
393	output with sprintf().
394
395	If your stdio requires a seek or eof between reads and writes on a
396	particular stream, so does Perl. (This doesn't apply to sysread()
397	and syswrite().)
398
399	While none of the built-in data types have any arbitrary size limits
400	(apart from memory size), there are still a few arbitrary limits: a
401	given variable name may not be longer than 251 characters. Line numbers
402	displayed by diagnostics are internally stored as short integers,
403	so they are limited to a maximum of 65535 (higher numbers usually being
404	affected by wraparound).
405
406	You may mail your bug reports (be sure to include full configuration
407	information as output by the myconfig program in the perl source
408	tree, or by C<perl -V>) to perlbug@perl.org . If you've succeeded
409	in compiling perl, the B<perlbug> script in the F<utils/> subdirectory
410	can be used to help mail in a bug report.
411
412	Perl actually stands for Pathologically Eclectic Rubbish Lister, but
413	don't tell anyone I said that.
414
415	=head1 NOTES
416
417	The Perl motto is "There's more than one way to do it." Divining
418	how many more is left as an exercise to the reader.
419
420	The three principal virtues of a programmer are Laziness,
421	Impatience, and Hubris. See the Camel Book for why.
422