perldoc - Look up Perl documentation in Pod format.
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.
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 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.
- -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.
- -U
- When running as the superuser, don't attempt drop
privileges for security. 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 '$"'
perldoc -v @+
perldoc -v DATA
- -T
- This specifies that the output is not to be sent to a
pager, but is to be sent directly to STDOUT.
-
-d destination-filename
- This specifies that the output is to be sent neither to a
pager nor to STDOUT, but is to be saved to the specified filename.
Example: "perldoc -oLaTeX -dtextwrapdocs.tex Text::Wrap"
-
-o output-formatname
- This specifies that you want Perldoc to try using a
Pod-formatting class for the output format that you specify. For example:
"-oman". This is actually just a wrapper around the
"-M" switch; using "-o formatname" just looks
for a loadable class by adding that format name (with different
capitalizations) to the end of different classname prefixes.
For example, "-oLaTeX" currently tries all of the following
classes: Pod::Perldoc::ToLaTeX Pod::Perldoc::Tolatex Pod::Perldoc::ToLatex
Pod::Perldoc::ToLATEX Pod::Simple::LaTeX Pod::Simple::latex
Pod::Simple::Latex Pod::Simple::LATEX Pod::LaTeX Pod::latex Pod::Latex
Pod::LATEX.
-
-M module-name
- This specifies the module that you want to try using for
formatting the pod. The class must at least provide a
"parse_from_file" method. For example: "perldoc
-MPod::Perldoc::ToChecker".
You can specify several classes to try by joining them with commas or
semicolons, as in "-MTk::SuperPod;Tk::Pod".
-
-w option:value or -w
option
- This specifies an option to call the formatter with.
For example, "-w textsize:15" will call
"$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.
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.
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 nobody/nogroup level.
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.
Up to 3.14_05, the switch
-v was used to produce verbose messages of
perldoc operation, which is now enabled by
-D.
perlpod, Pod::Perldoc
Current maintainer: Mark Allen "<
[email protected]>"
Past contributors are: brian d foy "<
[email protected]>" Adriano R.
Ferreira "<
[email protected]>", Sean M. Burke
"<
[email protected]>", Kenneth Albanowski
"<
[email protected]>", Andy Dougherty
"<
[email protected]>", and many others.