NAME
perlutil - utilities packaged with the Perl distribution
DESCRIPTION
Along with the Perl interpreter itself, the Perl distribution installs a range of utilities on your system. There are also several utilities which are used by the Perl distribution itself as part of the install process. This document exists to list all of these utilities, explain what they are for and provide pointers to each module's documentation, if appropriate.
LIST OF UTILITIES
Documentation
- perldoc
The main interface to Perl's documentation is
perldoc
, although if you're reading this, it's more than likely that you've already found it. perldoc will extract and format the documentation from any file in the current directory, any Perl module installed on the system, or any of the standard documentation pages, such as this one. Useperldoc <name>
to get information on any of the utilities described in this document. - pod2man and pod2text
If it's run from a terminal, perldoc will usually call pod2man to translate POD (Plain Old Documentation - see perlpod for an explanation) into a manpage, and then run man to display it; if man isn't available, pod2text will be used instead and the output piped through your favourite pager.
- pod2html and pod2latex
As well as these two, there are two other converters: pod2html will produce HTML pages from POD, and pod2latex, which produces LaTeX files.
- pod2usage
If you just want to know how to use the utilities described here, pod2usage will just extract the "USAGE" section; some of the utilities will automatically call pod2usage on themselves when you call them with
-help
. - podselect
pod2usage is a special case of podselect, a utility to extract named sections from documents written in POD. For instance, while utilities have "USAGE" sections, Perl modules usually have "SYNOPSIS" sections:
podselect -s "SYNOPSIS" ...
will extract this section for a given file. - podchecker
If you're writing your own documentation in POD, the podchecker utility will look for errors in your markup.
- splain
splain is an interface to perldiag - paste in your error message to it, and it'll explain it for you.
- roffitall
The
roffitall
utility is not installed on your system but lives in the pod/ directory of your Perl source kit; it converts all the documentation from the distribution to *roff format, and produces a typeset PostScript or text file of the whole lot.
Convertors
To help you convert legacy programs to Perl, we've included three conversion filters:
- a2p
a2p converts awk scripts to Perl programs; for example,
a2p -F:
on the simple awk script{print $2}
will produce a Perl program based around this code:while (<>) { ($Fld1,$Fld2) = split(/[:\n]/, $_, 9999); print $Fld2; }
- s2p and psed
Similarly, s2p converts sed scripts to Perl programs. s2p run on
s/foo/bar
will produce a Perl program based around this:while (<>) { chomp; s/foo/bar/g; print if $printit; }
When invoked as psed, it behaves as a sed implementation, written in Perl.
- find2perl
Finally, find2perl translates
find
commands to Perl equivalents which use the File::Find module. As an example,find2perl . -user root -perm 4000 -print
produces the following callback subroutine forFile::Find
:sub wanted { my ($dev,$ino,$mode,$nlink,$uid,$gid); (($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) && $uid == $uid{'root'}) && (($mode & 0777) == 04000); print("$name\n"); }
As well as these filters for converting other languages, the pl2pm utility will help you convert old-style Perl 4 libraries to new-style Perl5 modules.
Administration
- config_data
Query or change configuration of Perl modules that use Module::Build-based configuration files for features and config data.
- libnetcfg
To display and change the libnet configuration run the libnetcfg command.
- perlivp
The perlivp program is set up at Perl source code build time to test the Perl version it was built under. It can be used after running
make install
(or your platform's equivalent procedure) to verify that perl and its libraries have been installed correctly.
Development
There are a set of utilities which help you in developing Perl programs, and in particular, extending Perl with C.
- perlbug
perlbug is the recommended way to report bugs in the perl interpreter itself or any of the standard library modules back to the developers; please read through the documentation for perlbug thoroughly before using it to submit a bug report.
- h2ph
Back before Perl had the XS system for connecting with C libraries, programmers used to get library constants by reading through the C header files. You may still see
require 'syscall.ph'
or similar around - the .ph file should be created by running h2ph on the corresponding .h file. See the h2ph documentation for more on how to convert a whole bunch of header files at once. - c2ph and pstruct
c2ph and pstruct, which are actually the same program but behave differently depending on how they are called, provide another way of getting at C with Perl - they'll convert C structures and union declarations to Perl code. This is deprecated in favour of h2xs these days.
- h2xs
h2xs converts C header files into XS modules, and will try and write as much glue between C libraries and Perl modules as it can. It's also very useful for creating skeletons of pure Perl modules.
- enc2xs
enc2xs builds a Perl extension for use by Encode from either Unicode Character Mapping files (.ucm) or Tcl Encoding Files (.enc). Besides being used internally during the build process of the Encode module, you can use enc2xs to add your own encoding to perl. No knowledge of XS is necessary.
- xsubpp
xsubpp is a compiler to convert Perl XS code into C code. It is typically run by the makefiles created by ExtUtils::MakeMaker.
xsubpp will compile XS code into C code by embedding the constructs necessary to let C functions manipulate Perl values and creates the glue necessary to let Perl access those functions.
- dprofpp
Perl comes with a profiler, the Devel::DProf module. The dprofpp utility analyzes the output of this profiler and tells you which subroutines are taking up the most run time. See Devel::DProf for more information.
- prove
prove is a command-line interface to the test-running functionality of of Test::Harness. It's an alternative to
make test
. - corelist
A command-line front-end to
Module::CoreList
, to query what modules were shipped with given versions of perl.
General tools
A few general-purpose tools are shipped with perl, mostly because they came along modules included in the perl distribution.
- piconv
piconv is a Perl version of iconv, a character encoding converter widely available for various Unixen today. This script was primarily a technology demonstrator for Perl 5.8.0, but you can use piconv in the place of iconv for virtually any case.
- ptar
ptar is a tar-like program, written in pure Perl.
- ptardiff
ptardiff is a small utility that produces a diff between an extracted archive and an unextracted one. (Note that this utility requires the
Text::Diff
module to function properly; this module isn't distributed with perl, but is available from the CPAN.) - shasum
This utility, that comes with the
Digest::SHA
module, is used to print or verify SHA checksums.
Installation
These utilities help manage extra Perl modules that don't come with the perl distribution.
- cpan
cpan is a command-line interface to CPAN.pm. It allows you to install modules or distributions from CPAN, or just get information about them, and a lot more. It is similar to the command line mode of the CPAN module,
perl -MCPAN -e shell
- cpanp
cpanp is, like cpan, a command-line interface to the CPAN, using the
CPANPLUS
module as a back-end. It can be used interactively or imperatively. - cpan2dist
cpan2dist is a tool to create distributions (or packages) from CPAN modules, then suitable for your package manager of choice. Support for specific formats are available from CPAN as
CPANPLUS::Dist::*
modules. - instmodsh
A little interface to ExtUtils::Installed to examine installed modules, validate your packlists and even create a tarball from an installed module.
SEE ALSO
perldoc, pod2man, perlpod, pod2html, pod2usage, podselect, podchecker, splain, perldiag, roffitall, a2p, s2p, find2perl, File::Find, pl2pm, perlbug, h2ph, c2ph, h2xs, dprofpp, Devel::DProf, enc2xs, xsubpp, cpan, cpanp, cpan2dist, instmodsh, piconv, prove, corelist, ptar, ptardiff, shasum