CPAN(1)                 Perl Programmers Reference Guide                 CPAN(1)

       cpan - easily interact with CPAN from the command line

               # with arguments and no switches, installs specified modules
               cpan module_name [ module_name ... ]

               # with switches, installs modules with extra behavior
               cpan [-cfFimtTw] module_name [ module_name ... ]

               # use local::lib
               cpan -I module_name [ module_name ... ]

               # one time mirror override for faster mirrors
               cpan -p ...

               # with just the dot, install from the distribution in the
               # current directory
               cpan .

               # without arguments, starts shell

               # without arguments, but some switches
               cpan [-ahpruvACDLOPX]

       This script provides a command interface (not a shell) to CPAN. At the
       moment it uses to do the work, but it is not a one-shot command
       runner for

       -a  Creates a autobundle with CPAN::Shell->autobundle.

       -A module [ module ... ]
           Shows the primary maintainers for the specified modules.

       -c module
           Runs a `make clean` in the specified module's directories.

       -C module [ module ... ]
           Show the Changes files for the specified modules

       -D module [ module ... ]
           Show the module details. This prints one line for each out-of-date
           module (meaning, modules locally installed but have newer versions on
           CPAN).  Each line has three columns: module name, local version, and
           CPAN version.

       -f  Force the specified action, when it normally would have failed. Use
           this to install a module even if its tests fail. When you use this
           option, -i is not optional for installing a module when you need to
           force it:

                   % cpan -f -i Module::Foo

       -F  Turn off's attempts to lock anything. You should be careful
           with this since you might end up with multiple scripts trying to muck
           in the same directory. This isn't so much of a concern if you're
           loading a special config with "-j", and that config sets up its own
           work directories.

       -g module [ module ... ]
           Downloads to the current directory the latest distribution of the

       -G module [ module ... ]

           Download to the current directory the latest distribution of the
           modules, unpack each distribution, and create a git repository for
           each distribution.

           If you want this feature, check out Yanick Champoux's
           "Git::CPAN::Patch" distribution.

       -h  Print a help message and exit. When you specify "-h", it ignores all
           of the other options and arguments.

       -i module [ module ... ]
           Install the specified modules. With no other switches, this switch is

       -I  Load "local::lib" (think like "-I" for loading lib paths). Too bad
           "-l" was already taken.

           Load the file that has the CPAN configuration data. This should have
           the same format as the standard CPAN/ file, which defines
           $CPAN::Config as an anonymous hash.

       -J  Dump the configuration in the same format that uses. This is
           useful for checking the configuration as well as using the dump as a
           starting point for a new, custom configuration.

       -l  List all installed modules with their versions

       -L author [ author ... ]
           List the modules by the specified authors.

       -m  Make the specified modules.

       -M mirror1,mirror2,...
           A comma-separated list of mirrors to use for just this run. The "-P"
           option can find them for you automatically.

       -n  Do a dry run, but don't actually install anything. (unimplemented)

       -O  Show the out-of-date modules.

       -p  Ping the configured mirrors and print a report

       -P  Find the best mirrors you could be using and use them for the current

       -r  Recompiles dynamically loaded modules with CPAN::Shell->recompile.

       -s  Drop in the shell. This command does this automatically if
           you don't specify any arguments.

       -t module [ module ... ]
           Run a `make test` on the specified modules.

       -T  Do not test modules. Simply install them.

       -u  Upgrade all installed modules. Blindly doing this can really break
           things, so keep a backup.

       -v  Print the script version and version then exit.

       -V  Print detailed information about the cpan client.


           Turn on cpan warnings. This checks various things, like directory
           permissions, and tells you about problems you might have.

       -x module [ module ... ]
           Find close matches to the named modules that you think you might have
           mistyped. This requires the optional installation of
           Text::Levenshtein or Text::Levenshtein::Damerau.

       -X  Dump all the namespaces to standard output.

               # print a help message
               cpan -h

               # print the version numbers
               cpan -v

               # create an autobundle
               cpan -a

               # recompile modules
               cpan -r

               # upgrade all installed modules
               cpan -u

               # install modules ( sole -i is optional )
               cpan -i Netscape::Booksmarks Business::ISBN

               # force install modules ( must use -i )
               cpan -fi CGI::Minimal URI

               # install modules but without testing them
               cpan -Ti CGI::Minimal URI

   Environment variables
       There are several components in that use environment variables.
       The build tools, ExtUtils::MakeMaker and Module::Build use some, while
       others matter to the levels above them. Some of these are specified by
       the Perl Toolchain Gang:

       Lancaster Concensus:

       Oslo Concensus:

           Assume no one is paying attention and skips prompts for distributions
           that do that correctly. cpan(1) sets this to 1 unless it already has
           a value (even if that value is false).

           Use the default answer for a prompted questions. cpan(1) sets this to
           1 unless it already has a value (even if that value is false).

           As with "PERL5OPT", a string of additional cpan(1) options to add to
           those you specify on the command line.

           The log level to use, with either the embedded, minimal logger or
           Log::Log4perl if it is installed. Possible values are the same as the
           "Log::Log4perl" levels: "TRACE", "DEBUG", "INFO", "WARN", "ERROR",
           and "FATAL". The default is "INFO".

           The path to the "git" binary to use for the Git features. The default
           is "/usr/local/bin/git".

       The script exits with zero if it thinks that everything worked, or a
       positive number if it thinks that something failed. Note, however, that
       in some cases it has to divine a failure by the output of things it does
       not control. For now, the exit codes are vague:

               1       An unknown error

               2       The was an external problem

               4       There was an internal problem with the script

               8       A module failed to install

       * one shot configuration values from the command line

       * none noted

       Most behaviour, including environment variables and configuration, comes
       directly from

       This code is in Github in the repository:


       The source used to be tracked separately in another GitHub repo, but the
       canonical source is now in the above repo.

       Japheth Cleaver added the bits to allow a forced install (-f).

       Jim Brandt suggest and provided the initial implementation for the up-to-
       date and Changes features.

       Adam Kennedy pointed out that exit() causes problems on Windows where
       this script ends up with a .bat extension

       brian d foy, "<>"

       Copyright (c) 2001-2015, brian d foy, All Rights Reserved.

       You may redistribute this under the same terms as Perl itself.

perl v5.30.3                       2021-11-13                            CPAN(1)