perldoc - Look up Perl documentation in Pod format. at Linux.org

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PERLDOC(1) User Contributed Perl Documentation 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

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.

perlfaq[1-9] and print the entries matching the regular expression.

Example:

perldoc -q shuffle

-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.
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.)

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.