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PERL(1)		       Perl Programmers	Reference Guide		       PERL(1)

       perl - The Perl 5 language interpreter

       perl [ -sTtuUWX ]      [	-hv ] [	-V[:configvar] ]
	    [ -cw ] [ -d[t][:debugger] ] [ -D[number/list] ]
	    [ -pna ] [ -Fpattern ] [ -l[octal] ] [ -0[octal/hexadecimal] ]
	    [ -Idir ] [	-m[-]module ] [	-M[-]'module...' ] [ -f	]
	    [ -C [number/list] ]      [	-S ]	  [ -x[dir] ]
	    [ -i[extension] ]
	    [ [-e|-E] 'command'	] [ -- ] [ programfile ] [ argument ]...

       For more	information on these options, you can run "perldoc perlrun".

       The perldoc program gives you access to all the documentation that
       comes with Perl.	 You can get more documentation, tutorials and
       community support online	at <>.

       If you're new to	Perl, you should start by running "perldoc perlintro",
       which is	a general intro	for beginners and provides some	background to
       help you	navigate the rest of Perl's extensive documentation.  Run
       "perldoc	perldoc" to learn more things you can do with perldoc.

       For ease	of access, the Perl manual has been split up into several

	   perl		       Perl overview (this section)
	   perlintro	       Perl introduction for beginners
	   perlrun	       Perl execution and options
	   perltoc	       Perl documentation table	of contents

	   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

	   perlootut	       Perl OO tutorial	for beginners

	   perlperf	       Perl Performance	and Optimization Techniques

	   perlstyle	       Perl style guide

	   perlcheat	       Perl cheat sheet
	   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

   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
	   perldocstyle	       Perl style guide	for core docs
	   perlpodstyle	       Perl POD	style guide
	   perldiag	       Perl diagnostic messages
	   perldeprecation     Perl deprecations
	   perllexwarn	       Perl warnings and their control
	   perldebug	       Perl debugging
	   perlvar	       Perl predefined variables
	   perlre	       Perl regular expressions, the rest of the story
	   perlrebackslash     Perl regular expression backslash sequences
	   perlrecharclass     Perl regular expression character classes
	   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

	   perlport	       Perl portability	guide
	   perllocale	       Perl locale support
	   perluniintro	       Perl Unicode introduction
	   perlunicode	       Perl Unicode support
	   perlunicook	       Perl Unicode cookbook
	   perlunifaq	       Perl Unicode FAQ
	   perluniprops	       Index of	Unicode	properties in Perl
	   perlunitut	       Perl Unicode tutorial
	   perlebcdic	       Considerations for running Perl on EBCDIC platforms

	   perlsec	       Perl security
	   perlsecpolicy       Perl security report handling policy

	   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
	   perlpragma	       Perl modules: writing a user pragma

	   perlutil	       utilities packaged with the Perl	distribution

	   perlfilter	       Perl source filters

	   perldtrace	       Perl's support for DTrace

	   perlglossary	       Perl Glossary

   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
	   perlxstypemap       Perl XS C/Perl type conversion tools
	   perlclib	       Internal	replacements for standard C library functions
	   perlguts	       Perl internal functions for those doing extensions
	   perlcall	       Perl calling conventions	from C
	   perlmroapi	       Perl method resolution plugin interface
	   perlreapi	       Perl regular expression plugin interface
	   perlreguts	       Perl regular expression engine internals

	   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
	   perlsource	       Guide to	the Perl source	tree
	   perlinterp	       Overview	of the Perl interpreter	source and how it works
	   perlhacktut	       Walk through the	creation of a simple C code patch
	   perlhacktips	       Tips for	Perl core C code hacking
	   perlpolicy	       Perl development	policies
	   perlgov	       Perl Rules of Governance
	   perlgit	       Using git with the Perl repository

	   perlhist	       Perl history records
	   perldelta	       Perl changes since previous version
	   perl5341delta       Perl changes in version 5.34.1
	   perl5340delta       Perl changes in version 5.34.0
	   perl5321delta       Perl changes in version 5.32.1
	   perl5320delta       Perl changes in version 5.32.0
	   perl5303delta       Perl changes in version 5.30.3
	   perl5302delta       Perl changes in version 5.30.2
	   perl5301delta       Perl changes in version 5.30.1
	   perl5300delta       Perl changes in version 5.30.0
	   perl5283delta       Perl changes in version 5.28.3
	   perl5282delta       Perl changes in version 5.28.2
	   perl5281delta       Perl changes in version 5.28.1
	   perl5280delta       Perl changes in version 5.28.0
	   perl5263delta       Perl changes in version 5.26.3
	   perl5262delta       Perl changes in version 5.26.2
	   perl5261delta       Perl changes in version 5.26.1
	   perl5260delta       Perl changes in version 5.26.0
	   perl5244delta       Perl changes in version 5.24.4
	   perl5243delta       Perl changes in version 5.24.3
	   perl5242delta       Perl changes in version 5.24.2
	   perl5241delta       Perl changes in version 5.24.1
	   perl5240delta       Perl changes in version 5.24.0
	   perl5224delta       Perl changes in version 5.22.4
	   perl5223delta       Perl changes in version 5.22.3
	   perl5222delta       Perl changes in version 5.22.2
	   perl5221delta       Perl changes in version 5.22.1
	   perl5220delta       Perl changes in version 5.22.0
	   perl5203delta       Perl changes in version 5.20.3
	   perl5202delta       Perl changes in version 5.20.2
	   perl5201delta       Perl changes in version 5.20.1
	   perl5200delta       Perl changes in version 5.20.0
	   perl5184delta       Perl changes in version 5.18.4
	   perl5182delta       Perl changes in version 5.18.2
	   perl5181delta       Perl changes in version 5.18.1
	   perl5180delta       Perl changes in version 5.18.0
	   perl5163delta       Perl changes in version 5.16.3
	   perl5162delta       Perl changes in version 5.16.2
	   perl5161delta       Perl changes in version 5.16.1
	   perl5160delta       Perl changes in version 5.16.0
	   perl5144delta       Perl changes in version 5.14.4
	   perl5143delta       Perl changes in version 5.14.3
	   perl5142delta       Perl changes in version 5.14.2
	   perl5141delta       Perl changes in version 5.14.1
	   perl5140delta       Perl changes in version 5.14.0
	   perl5125delta       Perl changes in version 5.12.5
	   perl5124delta       Perl changes in version 5.12.4
	   perl5123delta       Perl changes in version 5.12.3
	   perl5122delta       Perl changes in version 5.12.2
	   perl5121delta       Perl changes in version 5.12.1
	   perl5120delta       Perl changes in version 5.12.0
	   perl5101delta       Perl changes in version 5.10.1
	   perl5100delta       Perl changes in version 5.10.0
	   perl589delta	       Perl changes in version 5.8.9
	   perl588delta	       Perl changes in version 5.8.8
	   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
	   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

	   perlbook	       Perl book information
	   perlcommunity       Perl community information

	   perldoc	       Look up Perl documentation in Pod format

	   perlexperiment      A listing of experimental features in Perl

	   perlartistic	       Perl Artistic License
	   perlgpl	       GNU General Public License

	   perlcn	       Perl for	Simplified Chinese (in UTF-8)
	   perljp	       Perl for	Japanese (in EUC-JP)
	   perlko	       Perl for	Korean (in EUC-KR)
	   perltw	       Perl for	Traditional Chinese (in	Big5)

	   perlaix	       Perl notes for AIX
	   perlamiga	       Perl notes for AmigaOS
	   perlandroid	       Perl notes for Android
	   perlbs2000	       Perl notes for POSIX-BC BS2000
	   perlcygwin	       Perl notes for Cygwin
	   perlfreebsd	       Perl notes for FreeBSD
	   perlhaiku	       Perl notes for Haiku
	   perlhpux	       Perl notes for HP-UX
	   perlhurd	       Perl notes for Hurd
	   perlirix	       Perl notes for Irix
	   perllinux	       Perl notes for Linux
	   perlmacosx	       Perl notes for Mac OS X
	   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
	   perlriscos	       Perl notes for RISC OS
	   perlsolaris	       Perl notes for Solaris
	   perlsynology	       Perl notes for Synology
	   perltru64	       Perl notes for Tru64
	   perlvms	       Perl notes for VMS
	   perlvos	       Perl notes for Stratus VOS
	   perlwin32	       Perl notes for Windows

   Stubs for Deleted Documents

       On a Unix-like system, these documentation files	will usually also be
       available as manpages for use with the man program.

       Some documentation is not available as man pages, so if a cross-
       reference is not	found by man, try it with perldoc.  Perldoc can	also
       take you	directly to documentation for functions	(with the -f switch).
       See "perldoc --help" (or	"perldoc perldoc" or "man perldoc") for	other
       helpful options perldoc has to offer.

       In general, if something	strange	has gone wrong with your program and
       you're not sure where you should	look for help, try making your code
       comply with use strict and use warnings.	 These will often point	out
       exactly where the trouble is.

       Perl officially stands for Practical Extraction and Report Language,
       except when it doesn't.

       Perl was	originally a language optimized	for scanning arbitrary text
       files, extracting information from those	text files, and	printing
       reports based on	that information.  It quickly became a good language
       for many	system management tasks. Over the years, Perl has grown	into a
       general-purpose programming language. It's widely used for everything
       from quick "one-liners" to full-scale application development.

       The language is intended	to be practical	(easy to use, efficient,
       complete) rather	than beautiful (tiny, elegant, minimal).  It combines
       (in the author's	opinion, anyway) some of the best features of sed,
       awk, and	sh, making it familiar and easy	to use for Unix	users to whip
       up quick	solutions to annoying problems.	 Its general-purpose
       programming facilities support procedural, functional, and object-
       oriented	programming paradigms, making Perl a comfortable language for
       the long	haul on	major projects,	whatever your bent.

       Perl's roots in text processing haven't been forgotten over the years.
       It still	boasts some of the most	powerful regular expressions to	be
       found anywhere, and its support for Unicode text	is world-class.	 It
       handles all kinds of structured text, too, through an extensive
       collection of extensions.  Those	libraries, collected in	the CPAN,
       provide ready-made solutions to an astounding array of problems.	 When
       they haven't set	the standard themselves, they steal from the best --
       just like Perl itself.

       Perl is available for most operating systems, including virtually all
       Unix-like platforms.  See "Supported Platforms" in perlport for a

       See "ENVIRONMENT" in perlrun.

       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 .

	"@INC"		       locations of perl libraries

       "@INC" above is a reference to the built-in variable of the same	name;
       see perlvar for more information.

SEE ALSO	    the	Perl homepage	    Perl articles	    the	Comprehensive Perl Archive	    the	Perl Mongers

       Using the "use strict" pragma ensures that all variables	are properly
       declared	and prevents other misuses of legacy Perl features.  These are
       enabled by default within the scope of "use v5.12" (or higher).

       The "use	warnings" pragma produces some lovely diagnostics.  It is
       enabled by default when you say "use v5.35" (or higher).	 One can also
       use the -w flag,	but its	use is normally	discouraged, because it	gets
       applied to all executed Perl code, including that not under your

       See perldiag for	explanations of	all Perl's diagnostics.	 The "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 -e switches, each -e is counted as one

       Setuid scripts have additional constraints that can produce error
       messages	such as	"Insecure dependency".	See perlsec.

       Did we mention that you should definitely consider using	the use
       warnings	pragma?

       The behavior implied by the use warnings	pragma 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

       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

       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 submit your bug reports (be sure	to include full	configuration
       information as output by	the myconfig program in	the perl source	tree,
       or by "perl -V")	to <>.

       Perl actually stands for	Pathologically Eclectic	Rubbish	Lister,	but
       don't tell anyone I said	that.

       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.

perl v5.36.0			  2022-05-21			       PERL(1)


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