perldoc - perldoc.perl.org

Perl Programming Documentation
Download Perl
Explore

Manual

- Overview
- Tutorials
- FAQs
- History / Changes
- License

Reference

- Language
- Functions
- Operators
- Special Variables
- Pragmas
- Utilities
- Internals
- Platform Specific

Modules

- A • B • C • D • E
- F • G • H • I • L
- M • N • O • P • S
- T • U • X

Tools

- Preferences

# perldoc

Perl 5 version 12.2 documentation
Go to top
Show page index • Show recent pages
Recently read

# perldoc

- SYNOPSIS
- DESCRIPTION
- OPTIONS
- SECURITY
- ENVIRONMENT
- CHANGES
- SEE ALSO
- AUTHOR

# SYNOPSIS

perldoc [-h] [-D] [-t] [-u] [-m] [-l] [-F] [-i] [-V] [-T] [-r] [-ddestination_file] [-oformatname] [-MFormatterClassName] [-wformatteroption:value] [-nnroff-replacement] [-X] [-L language_code] PageName|ModuleName|ProgramName

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 `pod2man | nroff -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

- -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 right 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 a "=" 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 to specify the language code for desired language translation. If `POD2::<language_code>` package doesn't exist (or isn't installed in your system), the switch will be ignored. All available translation packages should be found under the `POD2::` namespace. See POD2::IT (or POD2::FR) in order to see how to create and integrate new localized `POD2::*` pod documentation packages in Pod::Perldoc.

- PageName|ModuleName|ProgramName

  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 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 nroff

- -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 `-oman` , `-otext` , `-otk` , `-ortf` , `-oxml` , and so on, depending on what modules you have on hand; or exactly specify the formatter class with `-MPod::Perldoc::ToMan` 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.)

`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 `-v` 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: Adriano R. Ferreira <ferreira@cpan.org>

Past contributors are: Sean M. Burke <sburke@cpan.org>, Kenneth Albanowski <kjahds@kjahds.com>, Andy Dougherty <doughera@lafcol.lafayette.edu>, and many others.

Page index

- SYNOPSIS
- DESCRIPTION
- OPTIONS
- SECURITY
- ENVIRONMENT
- CHANGES
- SEE ALSO
- AUTHOR