perlutil - utilities packaged with the Perl distribution


   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.


      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.

      As well as these two, there is another converter: pod2html will
      produce HTML pages from POD.

      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".

      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.

      If you're writing your own documentation in POD, the podchecker
      utility will look for errors in your markup.

      splain is an interface to perldiag - paste in your error message to
      it, and it'll explain it for you.

      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.

   To help you convert legacy programs to more modern Perl, the pl2pm
   utility will help you convert old-style Perl 4 libraries to new-style
   Perl5 modules.

      To display and change the libnet configuration run the libnetcfg

      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.

   There are a set of utilities which help you in developing Perl
   programs, and in particular, extending Perl with C.

      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.

      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.

      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 ''" 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 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 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 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 is a command-line interface to the test-running functionality
      of Test::Harness.  It's an alternative to "make test".

      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 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 is a tar-like program, written in pure Perl.

      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 is a utility to apply pattern matching to the contents of
      files in a tar archive.

      This utility, that comes with the "Digest::SHA" module, is used to
      print or verify SHA checksums.

      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.

   These utilities help manage extra Perl modules that don't come with the
   perl distribution.

      cpan is a command-line interface to  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

      A little interface to ExtUtils::Installed to examine installed
      modules, validate your packlists and even create a tarball from an
      installed module.


   perldoc, pod2man, perlpod, pod2html, pod2usage, podselect, podchecker,
   splain, perldiag, "roffitall|roffitall", File::Find, pl2pm, perlbug,
   h2ph, c2ph, h2xs, enc2xs, xsubpp, cpan, instmodsh, piconv, prove,
   corelist, ptar, ptardiff, shasum, zipdetails


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