- 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.
Prints out a brief help message.
Describes search for the item in detail.
Display docs using plain text converter, instead of nroff. This may be faster, but it probably won't look as nice.
Skip the real Pod formatting, and just show the raw Pod source (Unformatted)
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.
Display only the file name of the module found.
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.
Consider arguments as file names; no search in directories will be performed. Implies -U if run as the superuser.
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
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
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
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
This specifies that the output is not to be sent to a pager, but is to be sent directly to STDOUT.
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
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.
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
.
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.
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.
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.
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".
Specify replacement for groff
Recursive search.
Ignore case.
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.
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.