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. Use
"perldoc <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
- As well as these two, there is another converter: pod2html will
produce HTML pages from POD.
- 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.
Converters¶
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]/, $_, -1);
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 $printit;
}
When invoked as psed, it behaves as a sed implementation,
written in Perl.
- find2perl
- Finally, find2perl translates "find" commands to Perl
equivalents which use the File::Find module. As an example,
"find2perl . -user root -perm 4000 -print" produces the
following callback subroutine for "File::Find":
sub wanted {
my ($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.
- perlthanks
- This program provides an easy way to send a thank-you message back to the
authors and maintainers of perl. It's just perlbug installed under
another name.
- 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.
- prove
- prove is a command-line interface to the test-running functionality
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.
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 v5.8.0, 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.)
- ptargrep
- ptargrep is a utility to apply pattern matching to the contents of
files in a tar archive.
- shasum
- This utility, that comes with the "Digest::SHA" module, is used
to print or verify SHA checksums.
- zipdetails
- zipdetails displays information about the internal record structure of the
zip file. It is not concerned with displaying any details of the
compressed data stored in the zip file.
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
- 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|roffitall", a2p, s2p, find2perl, File::Find,
pl2pm, perlbug, h2ph, c2ph, h2xs, enc2xs, xsubpp, cpan, instmodsh, piconv,
prove, corelist, ptar, ptardiff, shasum, zipdetails