perldoc(1)


NAME

   perldoc - Look up Perl documentation in Pod format.

SYNOPSIS

       perldoc [-h] [-D] [-t] [-u] [-m] [-l] [-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 a piece of documentation in .pod format that is
   embedded in the perl installation tree or in a perl script, and
   displays it via "groff -man | $PAGER". (In addition, if running under
   HP-UX, "col -x" will be used.) This is primarily used for the
   documentation for the perl library 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
   documentation, 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
        (Unformatted)

   -m module
        Display the entire module: both code and unformatted pod
        documentation.  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.

   -F   Consider arguments as file names; no search in directories will be
        performed.

   -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: "perldoc -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 "-oformatname" 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::Simple::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 object 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
        optionname: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 "$Config{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 packages 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::Basename") 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
   security 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.

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
   "PERLLIB" 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 working 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
   "PERLDOC_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),
   "perldoc" 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
   perldoc 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 Albanowski "<kjahds@kjahds.com>", Andy Dougherty
   "<doughera@lafcol.lafayette.edu>", and many others.





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