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PERLDOC(1)		Perl Programmers Reference Guide	      PERLDOC(1)

NAME
     perldoc - Look up Perl documentation in Pod format.

SYNOPSIS
	 perldoc [-h] [-D] [-t] [-u] [-m] [-l] [-U] [-F]
	     [-i] [-V] [-T] [-r]
	     [-d destination_file]
	     [-o formatname]
	     [-M FormatterClassName]
	     [-w formatteroption:value]
	     [-n nroff-replacement]
	     [-X]
	     [-L language_code]
	     PageName|ModuleName|ProgramName|URL

     Examples:

	 perldoc -f BuiltinFunction

	 perldoc -L it -f BuiltinFunction

	 perldoc -q FAQ Keyword

	 perldoc -L fr -q FAQ Keyword

	 perldoc -v PerlVariable

	 perldoc -a PerlAPI

     See below for more description of the switches.

DESCRIPTION
     perldoc looks up documentation in .pod format that is embedded in the perl
     installation tree or in a perl script, and displays it using a variety of
     formatters.  This is primarily used for the documentation for the perl li-
     brary modules.

     Your system may also have man pages installed for those modules, in which
     case you can probably just use the man(1) command.

     If you are looking for a table of contents to the Perl library modules doc-
     umentation, see the perltoc page.

OPTIONS
     -h   Prints out a brief help message.

     -D   Describes search for the item in detail.

     -t   Display docs using plain text converter, instead of nroff. This may be
	  faster, but it probably won't look as nice.

     -u   Skip the real Pod formatting, and just show the raw Pod source (Unfor-
	  matted)

     -m module
	  Display the entire module: both code and unformatted pod documenta-
	  tion.  This may be useful if the docs don't explain a function in the
	  detail you need, and you'd like to inspect the code directly; perldoc
	  will find the file for you and simply hand it off for display.

     -l   Display only the file name of the module found.

     -U   When running as the superuser, don't attempt drop privileges for secu-
	  rity.  This option is implied with -F.

	  NOTE: Please see the heading SECURITY below for more information.

     -F   Consider arguments as file names; no search in directories will be
	  performed.  Implies -U if run as the superuser.

     -f perlfunc
	  The -f option followed by the name of a perl built-in function will
	  extract the documentation of this function from perlfunc.

	  Example:

		perldoc -f sprintf

     -q perlfaq-search-regexp
	  The -q option takes a regular expression as an argument.  It will
	  search the question headings in perlfaq[1-9] and print the entries
	  matching the regular expression.

	  Example:

	       perldoc -q shuffle

     -a perlapifunc
	  The -a option followed by the name of a perl api function will extract
	  the documentation of this function from perlapi.

	  Example:

	       perldoc -a newHV

     -v perlvar
	  The -v option followed by the name of a Perl predefined variable will
	  extract the documentation of this variable from perlvar.

	  Examples:

	       perldoc -v '$"'
	       perldoc -v @+
	       perldoc -v DATA

     -T   This specifies that the output is not to be sent to a pager, but is to
	  be sent directly to STDOUT.

     -d destination-filename
	  This specifies that the output is to be sent neither to a pager nor to
	  STDOUT, but is to be saved to the specified filename.  Example: "perl-
	  doc -oLaTeX -dtextwrapdocs.tex Text::Wrap"

     -o output-formatname
	  This specifies that you want Perldoc to try using a Pod-formatting
	  class for the output format that you specify.  For example: "-oman".
	  This is actually just a wrapper around the "-M" switch; using "-ofor-
	  matname" just looks for a loadable class by adding that format name
	  (with different capitalizations) to the end of different classname
	  prefixes.

	  For example, "-oLaTeX" currently tries all of the following classes:
	  Pod::Perldoc::ToLaTeX Pod::Perldoc::Tolatex Pod::Perldoc::ToLatex
	  Pod::Perldoc::ToLATEX Pod::Simple::LaTeX Pod::Simple::latex Pod::Sim-
	  ple::Latex Pod::Simple::LATEX Pod::LaTeX Pod::latex Pod::Latex
	  Pod::LATEX.

     -M module-name
	  This specifies the module that you want to try using for formatting
	  the pod.  The class must at least provide a "parse_from_file" method.
	  For example: "perldoc -MPod::Perldoc::ToChecker".

	  You can specify several classes to try by joining them with commas or
	  semicolons, as in "-MTk::SuperPod;Tk::Pod".

     -w option:value or -w option
	  This specifies an option to call the formatter with.	For example, "-w
	  textsize:15" will call "$formatter->textsize(15)" on the formatter ob-
	  ject before it is used to format the object.	For this to be valid,
	  the formatter class must provide such a method, and the value you pass
	  should be valid.  (So if "textsize" expects an integer, and you do "-w
	  textsize:big", expect trouble.)

	  You can use "-w optionname" (without a value) as shorthand for "-w op-
	  tionname:TRUE".  This is presumably useful in cases of on/off features
	  like: "-w page_numbering".

	  You can use an "=" instead of the ":", as in: "-w textsize=15".  This
	  might be more (or less) convenient, depending on what shell you use.

     -X   Use an index if it is present. The -X option looks for an entry whose
	  basename matches the name given on the command line in the file "$Con-
	  fig{archlib}/pod.idx". The pod.idx file should contain fully qualified
	  filenames, one per line.

     -L language_code
	  This allows one to specify the language code for the desired language
	  translation. If the "POD2::<language_code>" package isn't installed in
	  your system, the switch is ignored.  All available translation pack-
	  ages are to be found under the "POD2::" namespace. See POD2::IT (or
	  POD2::FR) to see how to create new localized "POD2::*" documentation
	  packages and integrate them into Pod::Perldoc.

     PageName|ModuleName|ProgramName|URL
	  The item you want to look up.  Nested modules (such as "File::Base-
	  name") are specified either as "File::Basename" or "File/Basename".
	  You may also give a descriptive name of a page, such as "perlfunc".
	  For URLs, HTTP and HTTPS are the only kind currently supported.

	  For simple names like 'foo', when the normal search fails to find a
	  matching page, a search with the "perl" prefix is tried as well.  So
	  "perldoc intro" is enough to find/render "perlintro.pod".

     -n some-formatter
	  Specify replacement for groff

     -r   Recursive search.

     -i   Ignore case.

     -V   Displays the version of perldoc you're running.

SECURITY
     Because perldoc does not run properly tainted, and is known to have secu-
     rity issues, when run as the superuser it will attempt to drop privileges
     by setting the effective and real IDs to nobody's or nouser's account, or
     -2 if unavailable.  If it cannot relinquish its privileges, it will not
     run.

     See the "-U" option if you do not want this behavior but beware that there
     are significant security risks if you choose to use "-U".

     Since 3.26, using "-F" as the superuser also implies "-U" as opening most
     files and traversing directories requires privileges that are above the no-
     body/nogroup level.

ENVIRONMENT
     Any switches in the "PERLDOC" environment variable will be used before the
     command line arguments.

     Useful values for "PERLDOC" include "-oterm", "-otext", "-ortf", "-oxml",
     and so on, depending on what modules you have on hand; or the formatter
     class may be specified exactly with "-MPod::Perldoc::ToTerm" or the like.

     "perldoc" also searches directories specified by the "PERL5LIB" (or "PERL-
     LIB" if "PERL5LIB" is not defined) and "PATH" environment variables.  (The
     latter is so that embedded pods for executables, such as "perldoc" itself,
     are available.)

     In directories where either "Makefile.PL" or "Build.PL" exist, "perldoc"
     will add "." and "lib" first to its search path, and as long as you're not
     the superuser will add "blib" too.  This is really helpful if you're work-
     ing inside of a build directory and want to read through the docs even if
     you have a version of a module previously installed.

     "perldoc" will use, in order of preference, the pager defined in "PERL-
     DOC_PAGER", "MANPAGER", or "PAGER" before trying to find a pager on its
     own. ("MANPAGER" is not used if "perldoc" was told to display plain text or
     unformatted pod.)

     When using perldoc in it's "-m" mode (display module source code), "perl-
     doc" will attempt to use the pager set in "PERLDOC_SRC_PAGER".  A useful
     setting for this command is your favorite editor as in "/usr/bin/nano".
     (Don't judge me.)

     One useful value for "PERLDOC_PAGER" is "less -+C -E".

     Having PERLDOCDEBUG set to a positive integer will make perldoc emit even
     more descriptive output than the "-D" switch does; the higher the number,
     the more it emits.

CHANGES
     Up to 3.14_05, the switch -v was used to produce verbose messages of perl-
     doc operation, which is now enabled by -D.

SEE ALSO
     perlpod, Pod::Perldoc

AUTHOR
     Current maintainer: Mark Allen "<mallen@cpan.org>"

     Past contributors are: brian d foy "<bdfoy@cpan.org>" Adriano R. Ferreira
     "<ferreira@cpan.org>", Sean M. Burke "<sburke@cpan.org>", Kenneth Al-
     banowski "<kjahds@kjahds.com>", Andy Dougherty  "<doughera@laf-
     col.lafayette.edu>", and many others.

perl v5.42.2			   2019-02-13			      PERLDOC(1)
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