


CPAN(3p)         Perl Programmers Reference Guide        CPAN(3p)


NAME
       CPAN - query, download and build perl modules from CPAN
       sites

SYNOPSIS
       Interactive mode:

         perl -MCPAN -e shell

       --or--

         cpan

       Basic commands:

         # Modules:

         cpan> install Acme::Meta                       # in the shell

         CPAN::Shell->install("Acme::Meta");            # in perl

         # Distributions:

         cpan> install NWCLARK/Acme-Meta-0.02.tar.gz    # in the shell

         CPAN::Shell->
           install("NWCLARK/Acme-Meta-0.02.tar.gz");    # in perl

         # module objects:

         $mo = CPAN::Shell->expandany($mod);
         $mo = CPAN::Shell->expand("Module",$mod);      # same thing

         # distribution objects:

         $do = CPAN::Shell->expand("Module",$mod)->distribution;
         $do = CPAN::Shell->expandany($distro);         # same thing
         $do = CPAN::Shell->expand("Distribution",
                                   $distro);            # same thing

DESCRIPTION
       The CPAN module automates or at least simplifies the make
       and install of perl modules and extensions. It includes
       some primitive searching capabilities and knows how to use
       Net::FTP, LWP, and certain external download clients to
       fetch distributions from the net.

       These are fetched from one or more mirrored CPAN
       (Comprehensive Perl Archive Network) sites and unpacked in
       a dedicated directory.

       The CPAN module also supports named and versioned bundles
       of modules. Bundles simplify handling of sets of related
       modules. See Bundles below.



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       The package contains a session manager and a cache
       manager. The session manager keeps track of what has been
       fetched, built, and installed in the current session. The
       cache manager keeps track of the disk space occupied by
       the make processes and deletes excess space using a simple
       FIFO mechanism.

       All methods provided are accessible in a programmer style
       and in an interactive shell style.

   CPAN::shell([$prompt, $command]) Starting Interactive Mode
       Enter interactive mode by running

           perl -MCPAN -e shell

       or

           cpan

       which puts you into a readline interface. If
       "Term::ReadKey" and either of "Term::ReadLine::Perl" or
       "Term::ReadLine::Gnu" are installed, history and command
       completion are supported.

       Once at the command line, type "h" for one-page help
       screen; the rest should be self-explanatory.

       The function call "shell" takes two optional arguments:
       one the prompt, the second the default initial command
       line (the latter only works if a real ReadLine interface
       module is installed).

       The most common uses of the interactive modes are

       Searching for authors, bundles, distribution files and
       modules
         There are corresponding one-letter commands "a", "b",
         "d", and "m" for each of the four categories and
         another, "i" for any of the mentioned four. Each of the
         four entities is implemented as a class with slightly
         differing methods for displaying an object.

         Arguments to these commands are either strings exactly
         matching the identification string of an object, or
         regular expressions matched case-insensitively against
         various attributes of the objects. The parser only
         recognizes a regular expression when you enclose it with
         slashes.

         The principle is that the number of objects found
         influences how an item is displayed. If the search finds
         one item, the result is displayed with the rather
         verbose method "as_string", but if more than one is
         found, each object is displayed with the terse method



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         "as_glimpse".

         Examples:

           cpan> m Acme::MetaSyntactic
           Module id = Acme::MetaSyntactic
               CPAN_USERID  BOOK (Philippe Bruhat (BooK) <[...]>)
               CPAN_VERSION 0.99
               CPAN_FILE    B/BO/BOOK/Acme-MetaSyntactic-0.99.tar.gz
               UPLOAD_DATE  2006-11-06
               MANPAGE      Acme::MetaSyntactic - Themed metasyntactic variables names
               INST_FILE    /usr/local/lib/perl/5.10.0/Acme/MetaSyntactic.pm
               INST_VERSION 0.99
           cpan> a BOOK
           Author id = BOOK
               EMAIL        [...]
               FULLNAME     Philippe Bruhat (BooK)
           cpan> d BOOK/Acme-MetaSyntactic-0.99.tar.gz
           Distribution id = B/BO/BOOK/Acme-MetaSyntactic-0.99.tar.gz
               CPAN_USERID  BOOK (Philippe Bruhat (BooK) <[...]>)
               CONTAINSMODS Acme::MetaSyntactic Acme::MetaSyntactic::Alias [...]
               UPLOAD_DATE  2006-11-06
           cpan> m /lorem/
           Module  = Acme::MetaSyntactic::loremipsum (BOOK/Acme-MetaSyntactic-0.99.tar.gz)
           Module    Text::Lorem            (ADEOLA/Text-Lorem-0.3.tar.gz)
           Module    Text::Lorem::More      (RKRIMEN/Text-Lorem-More-0.12.tar.gz)
           Module    Text::Lorem::More::Source (RKRIMEN/Text-Lorem-More-0.12.tar.gz)
           cpan> i /berlin/
           Distribution    BEATNIK/Filter-NumberLines-0.02.tar.gz
           Module  = DateTime::TimeZone::Europe::Berlin (DROLSKY/DateTime-TimeZone-0.7904.tar.gz)
           Module    Filter::NumberLines    (BEATNIK/Filter-NumberLines-0.02.tar.gz)
           Author          [...]

         The examples illustrate several aspects: the first three
         queries target modules, authors, or distros directly and
         yield exactly one result. The last two use regular
         expressions and yield several results. The last one
         targets all of bundles, modules, authors, and distros
         simultaneously. When more than one result is available,
         they are printed in one-line format.

       "get", "make", "test", "install", "clean" modules or
       distributions
         These commands take any number of arguments and
         investigate what is necessary to perform the action. If
         the argument is a distribution file name (recognized by
         embedded slashes), it is processed. If it is a module,
         CPAN determines the distribution file in which this
         module is included and processes that, following any
         dependencies named in the module's META.yml or
         Makefile.PL (this behavior is controlled by the
         configuration parameter "prerequisites_policy".)

         "get" downloads a distribution file and untars or unzips



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         it, "make" builds it, "test" runs the test suite, and
         "install" installs it.

         Any "make" or "test" is run unconditionally. An

           install <distribution_file>

         is also run unconditionally. But for

           install <module>

         CPAN checks whether an install is needed and prints
         module up to date if the distribution file containing
         the module doesn't need updating.

         CPAN also keeps track of what it has done within the
         current session and doesn't try to build a package a
         second time regardless of whether it succeeded or not.
         It does not repeat a test run if the test has been run
         successfully before. Same for install runs.

         The "force" pragma may precede another command
         (currently: "get", "make", "test", or "install") to
         execute the command from scratch and attempt to continue
         past certain errors. See the section below on the
         "force" and the "fforce" pragma.

         The "notest" pragma skips the test part in the build
         process.

         Example:

             cpan> notest install Tk

         A "clean" command results in a

           make clean

         being executed within the distribution file's working
         directory.

       "readme", "perldoc", "look" module or distribution
         "readme" displays the README file of the associated
         distribution.  "Look" gets and untars (if not yet done)
         the distribution file, changes to the appropriate
         directory and opens a subshell process in that
         directory. "perldoc" displays the module's pod
         documentation in html or plain text format.

       "ls" author
       "ls" globbing_expression
         The first form lists all distribution files in and below
         an author's CPAN directory as stored in the CHECKUMS
         files distributed on CPAN. The listing recurses into



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         subdirectories.

         The second form limits or expands the output with shell
         globbing as in the following examples:

               ls JV/make*
               ls GSAR/*make*
               ls */*make*

         The last example is very slow and outputs extra progress
         indicators that break the alignment of the result.

         Note that globbing only lists directories explicitly
         asked for, for example FOO/* will not list
         FOO/bar/Acme-Sthg-n.nn.tar.gz. This may be regarded as a
         bug that may be changed in some future version.

       "failed"
         The "failed" command reports all distributions that
         failed on one of "make", "test" or "install" for some
         reason in the currently running shell session.

       Persistence between sessions
         If the "YAML" or the "YAML::Syck" module is installed a
         record of the internal state of all modules is written
         to disk after each step.  The files contain a signature
         of the currently running perl version for later perusal.

         If the configurations variable "build_dir_reuse" is set
         to a true value, then CPAN.pm reads the collected YAML
         files. If the stored signature matches the currently
         running perl, the stored state is loaded into memory
         such that persistence between sessions is effectively
         established.

       The "force" and the "fforce" pragma
         To speed things up in complex installation scenarios,
         CPAN.pm keeps track of what it has already done and
         refuses to do some things a second time. A "get", a
         "make", and an "install" are not repeated.  A "test" is
         repeated only if the previous test was unsuccessful. The
         diagnostic message when CPAN.pm refuses to do something
         a second time is one of Has already been
         "unwrapped|made|tested successfully" or something
         similar. Another situation where CPAN refuses to act is
         an "install" if the corresponding "test" was not
         successful.

         In all these cases, the user can override this stubborn
         behaviour by prepending the command with the word force,
         for example:






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           cpan> force get Foo
           cpan> force make AUTHOR/Bar-3.14.tar.gz
           cpan> force test Baz
           cpan> force install Acme::Meta

         Each forced command is executed with the corresponding
         part of its memory erased.

         The "fforce" pragma is a variant that emulates a "force
         get" which erases the entire memory followed by the
         action specified, effectively restarting the whole
         get/make/test/install procedure from scratch.

       Lockfile
         Interactive sessions maintain a lockfile, by default
         "~/.cpan/.lock".  Batch jobs can run without a lockfile
         and not disturb each other.

         The shell offers to run in downgraded mode when another
         process is holding the lockfile. This is an experimental
         feature that is not yet tested very well. This second
         shell then does not write the history file, does not use
         the metadata file, and has a different prompt.

       Signals
         CPAN.pm installs signal handlers for SIGINT and SIGTERM.
         While you are in the cpan-shell, it is intended that you
         can press "^C" anytime and return to the cpan-shell
         prompt. A SIGTERM will cause the cpan-shell to clean up
         and leave the shell loop. You can emulate the effect of
         a SIGTERM by sending two consecutive SIGINTs, which
         usually means by pressing "^C" twice.

         CPAN.pm ignores SIGPIPE. If the user sets
         "inactivity_timeout", a SIGALRM is used during the run
         of the "perl Makefile.PL" or "perl Build.PL" subprocess.

   CPAN::Shell
       The commands available in the shell interface are methods
       in the package CPAN::Shell. If you enter the shell
       command, your input is split by the
       Text::ParseWords::shellwords() routine, which acts like
       most shells do. The first word is interpreted as the
       method to be invoked, and the rest of the words are
       treated as the method's arguments.  Continuation lines are
       supported by ending a line with a literal backslash.

   autobundle
       "autobundle" writes a bundle file into the
       "$CPAN::Config->{cpan_home}/Bundle" directory. The file
       contains a list of all modules that are both available
       from CPAN and currently installed within @INC. The name of
       the bundle file is based on the current date and a
       counter.



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   hosts
       Note: this feature is still in alpha state and may change
       in future versions of CPAN.pm

       This commands provides a statistical overview over recent
       download activities. The data for this is collected in the
       YAML file "FTPstats.yml" in your "cpan_home" directory. If
       no YAML module is configured or YAML not installed, no
       stats are provided.

   mkmyconfig
       mkmyconfig() writes your own CPAN::MyConfig file into your
       "~/.cpan/" directory so that you can save your own
       preferences instead of the system-wide ones.

   recent ***EXPERIMENTAL COMMAND***
       The "recent" command downloads a list of recent uploads to
       CPAN and displays them slowly. While the command is
       running, a $SIG{INT} exits the loop after displaying the
       current item.

       Note: This command requires XML::LibXML installed.

       Note: This whole command currently is just a hack and will
       probably change in future versions of CPAN.pm, but the
       general approach will likely remain.

       Note: See also smoke

   recompile
       recompile() is a special command that takes no argument
       and runs the make/test/install cycle with brute force over
       all installed dynamically loadable extensions (aka XS
       modules) with 'force' in effect. The primary purpose of
       this command is to finish a network installation. Imagine
       you have a common source tree for two different
       architectures. You decide to do a completely independent
       fresh installation. You start on one architecture with the
       help of a Bundle file produced earlier. CPAN installs the
       whole Bundle for you, but when you try to repeat the job
       on the second architecture, CPAN responds with a "Foo up
       to date" message for all modules. So you invoke CPAN's
       recompile on the second architecture and you're done.

       Another popular use for "recompile" is to act as a rescue
       in case your perl breaks binary compatibility. If one of
       the modules that CPAN uses is in turn depending on binary
       compatibility (so you cannot run CPAN commands), then you
       should try the CPAN::Nox module for recovery.

   report Bundle|Distribution|Module
       The "report" command temporarily turns on the
       "test_report" config variable, then runs the "force test"
       command with the given arguments. The "force" pragma



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       reruns the tests and repeats every step that might have
       failed before.

   smoke ***EXPERIMENTAL COMMAND***
       *** WARNING: this command downloads and executes software
       from CPAN to your computer of completely unknown status.
       You should never do this with your normal account and
       better have a dedicated well separated and secured machine
       to do this. ***

       The "smoke" command takes the list of recent uploads to
       CPAN as provided by the "recent" command and tests them
       all. While the command is running $SIG{INT} is defined to
       mean that the current item shall be skipped.

       Note: This whole command currently is just a hack and will
       probably change in future versions of CPAN.pm, but the
       general approach will likely remain.

       Note: See also recent

   upgrade [Module|/Regex/]...
       The "upgrade" command first runs an "r" command with the
       given arguments and then installs the newest versions of
       all modules that were listed by that.

   The four "CPAN::*" Classes: Author, Bundle, Module,
       Distribution
       Although it may be considered internal, the class
       hierarchy does matter for both users and programmer.
       CPAN.pm deals with the four classes mentioned above, and
       those classes all share a set of methods. Classical single
       polymorphism is in effect. A metaclass object registers
       all objects of all kinds and indexes them with a string.
       The strings referencing objects have a separated namespace
       (well, not completely separated):

                Namespace                         Class

          words containing a "/" (slash)      Distribution
           words starting with Bundle::          Bundle
                 everything else            Module or Author

       Modules know their associated Distribution objects. They
       always refer to the most recent official release.
       Developers may mark their releases as unstable development
       versions (by inserting an underbar into the module version
       number which will also be reflected in the distribution
       name when you run 'make dist'), so the really hottest and
       newest distribution is not always the default.  If a
       module Foo circulates on CPAN in both version 1.23 and
       1.23_90, CPAN.pm offers a convenient way to install
       version 1.23 by saying




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           install Foo

       This would install the complete distribution file (say
       BAR/Foo-1.23.tar.gz) with all accompanying material. But
       if you would like to install version 1.23_90, you need to
       know where the distribution file resides on CPAN relative
       to the authors/id/ directory. If the author is BAR, this
       might be BAR/Foo-1.23_90.tar.gz; so you would have to say

           install BAR/Foo-1.23_90.tar.gz

       The first example will be driven by an object of the class
       CPAN::Module, the second by an object of class
       CPAN::Distribution.

   Integrating local directories
       Note: this feature is still in alpha state and may change
       in future versions of CPAN.pm

       Distribution objects are normally distributions from the
       CPAN, but there is a slightly degenerate case for
       Distribution objects, too, of projects held on the local
       disk. These distribution objects have the same name as the
       local directory and end with a dot. A dot by itself is
       also allowed for the current directory at the time CPAN.pm
       was used. All actions such as "make", "test", and
       "install" are applied directly to that directory. This
       gives the command "cpan ." an interesting touch: while the
       normal mantra of installing a CPAN module without CPAN.pm
       is one of

           perl Makefile.PL                 perl Build.PL
                  ( go and get prerequisites )
           make                             ./Build
           make test                        ./Build test
           make install                     ./Build install

       the command "cpan ." does all of this at once. It figures
       out which of the two mantras is appropriate, fetches and
       installs all prerequisites, takes care of them
       recursively, and finally finishes the installation of the
       module in the current directory, be it a CPAN module or
       not.

       The typical usage case is for private modules or working
       copies of projects from remote repositories on the local
       disk.

   Redirection
       The usual shell redirection symbols " | " and ">" are
       recognized by the cpan shell only when surrounded by
       whitespace. So piping to pager or redirecting output into
       a file works somewhat as in a normal shell, with the
       stipulation that you must type extra spaces.



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CONFIGURATION
       When the CPAN module is used for the first time, a
       configuration dialogue tries to determine a couple of site
       specific options. The result of the dialog is stored in a
       hash reference  $CPAN::Config in a file CPAN/Config.pm.

       Default values defined in the CPAN/Config.pm file can be
       overridden in a user specific file: CPAN/MyConfig.pm. Such
       a file is best placed in "$HOME/.cpan/CPAN/MyConfig.pm",
       because "$HOME/.cpan" is added to the search path of the
       CPAN module before the use() or require() statements. The
       mkmyconfig command writes this file for you.

       The "o conf" command has various bells and whistles:

       completion support
           If you have a ReadLine module installed, you can hit
           TAB at any point of the commandline and "o conf" will
           offer you completion for the built-in subcommands
           and/or config variable names.

       displaying some help: o conf help
           Displays a short help

       displaying current values: o conf [KEY]
           Displays the current value(s) for this config
           variable. Without KEY, displays all subcommands and
           config variables.

           Example:

             o conf shell

           If KEY starts and ends with a slash, the string in
           between is treated as a regular expression and only
           keys matching this regex are displayed

           Example:

             o conf /color/

       changing of scalar values: o conf KEY VALUE
           Sets the config variable KEY to VALUE. The empty
           string can be specified as usual in shells, with '' or
           ""

           Example:

             o conf wget /usr/bin/wget

       changing of list values: o conf KEY
       SHIFT|UNSHIFT|PUSH|POP|SPLICE|LIST
           If a config variable name ends with "list", it is a
           list. "o conf KEY shift" removes the first element of



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           the list, "o conf KEY pop" removes the last element of
           the list. "o conf KEYS unshift LIST" prepends a list
           of values to the list, "o conf KEYS push LIST" appends
           a list of valued to the list.

           Likewise, "o conf KEY splice LIST" passes the LIST to
           the corresponding splice command.

           Finally, any other list of arguments is taken as a new
           list value for the KEY variable discarding the
           previous value.

           Examples:

             o conf urllist unshift http://cpan.dev.local/CPAN
             o conf urllist splice 3 1
             o conf urllist http://cpan1.local http://cpan2.local ftp://ftp.perl.org

       reverting to saved: o conf defaults
           Reverts all config variables to the state in the saved
           config file.

       saving the config: o conf commit
           Saves all config variables to the current config file
           (CPAN/Config.pm or CPAN/MyConfig.pm that was loaded at
           start).

       The configuration dialog can be started any time later
       again by issuing the command " o conf init " in the CPAN
       shell. A subset of the configuration dialog can be run by
       issuing "o conf init WORD" where WORD is any valid config
       variable or a regular expression.

   Config Variables
       The following keys in the hash reference $CPAN::Config are
       currently defined:

         applypatch         path to external prg
         auto_commit        commit all changes to config variables to disk
         build_cache        size of cache for directories to build modules
         build_dir          locally accessible directory to build modules
         build_dir_reuse    boolean if distros in build_dir are persistent
         build_requires_install_policy
                            to install or not to install when a module is
                            only needed for building. yes|no|ask/yes|ask/no
         bzip2              path to external prg
         cache_metadata     use serializer to cache metadata
         check_sigs         if signatures should be verified
         colorize_debug     Term::ANSIColor attributes for debugging output
         colorize_output    boolean if Term::ANSIColor should colorize output
         colorize_print     Term::ANSIColor attributes for normal output
         colorize_warn      Term::ANSIColor attributes for warnings
         commandnumber_in_prompt
                            boolean if you want to see current command number



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         commands_quote     preferred character to use for quoting external
                            commands when running them. Defaults to double
                            quote on Windows, single tick everywhere else;
                            can be set to space to disable quoting
         connect_to_internet_ok
                            whether to ask if opening a connection is ok before
                            urllist is specified
         cpan_home          local directory reserved for this package
         curl               path to external prg
         dontload_hash      DEPRECATED
         dontload_list      arrayref: modules in the list will not be
                            loaded by the CPAN::has_inst() routine
         ftp                path to external prg
         ftp_passive        if set, the envariable FTP_PASSIVE is set for downloads
         ftp_proxy          proxy host for ftp requests
         ftpstats_period    max number of days to keep download statistics
         ftpstats_size      max number of items to keep in the download statistics
         getcwd             see below
         gpg                path to external prg
         gzip               location of external program gzip
         halt_on_failure    stop processing after the first failure of queued
                            items or dependencies
         histfile           file to maintain history between sessions
         histsize           maximum number of lines to keep in histfile
         http_proxy         proxy host for http requests
         inactivity_timeout breaks interactive Makefile.PLs or Build.PLs
                            after this many seconds inactivity. Set to 0 to
                            disable timeouts.
         index_expire       refetch index files after this many days
         inhibit_startup_message
                            if true, suppress the startup message
         keep_source_where  directory in which to keep the source (if we do)
         load_module_verbosity
                            report loading of optional modules used by CPAN.pm
         lynx               path to external prg
         make               location of external make program
         make_arg           arguments that should always be passed to 'make'
         make_install_make_command
                            the make command for running 'make install', for
                            example 'sudo make'
         make_install_arg   same as make_arg for 'make install'
         makepl_arg         arguments passed to 'perl Makefile.PL'
         mbuild_arg         arguments passed to './Build'
         mbuild_install_arg arguments passed to './Build install'
         mbuild_install_build_command
                            command to use instead of './Build' when we are
                            in the install stage, for example 'sudo ./Build'
         mbuildpl_arg       arguments passed to 'perl Build.PL'
         ncftp              path to external prg
         ncftpget           path to external prg
         no_proxy           don't proxy to these hosts/domains (comma separated list)
         pager              location of external program more (or any pager)
         password           your password if you CPAN server wants one
         patch              path to external prg



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         patches_dir        local directory containing patch files
         perl5lib_verbosity verbosity level for PERL5LIB additions
         prefer_installer   legal values are MB and EUMM: if a module comes
                            with both a Makefile.PL and a Build.PL, use the
                            former (EUMM) or the latter (MB); if the module
                            comes with only one of the two, that one will be
                            used no matter the setting
         prerequisites_policy
                            what to do if you are missing module prerequisites
                            ('follow' automatically, 'ask' me, or 'ignore')
         prefs_dir          local directory to store per-distro build options
         proxy_user         username for accessing an authenticating proxy
         proxy_pass         password for accessing an authenticating proxy
         randomize_urllist  add some randomness to the sequence of the urllist
         scan_cache         controls scanning of cache ('atstart' or 'never')
         shell              your favorite shell
         show_unparsable_versions
                            boolean if r command tells which modules are versionless
         show_upload_date   boolean if commands should try to determine upload date
         show_zero_versions boolean if r command tells for which modules $version==0
         tar                location of external program tar
         tar_verbosity      verbosity level for the tar command
         term_is_latin      deprecated: if true Unicode is translated to ISO-8859-1
                            (and nonsense for characters outside latin range)
         term_ornaments     boolean to turn ReadLine ornamenting on/off
         test_report        email test reports (if CPAN::Reporter is installed)
         trust_test_report_history
                            skip testing when previously tested ok (according to
                            CPAN::Reporter history)
         unzip              location of external program unzip
         urllist            arrayref to nearby CPAN sites (or equivalent locations)
         use_sqlite         use CPAN::SQLite for metadata storage (fast and lean)
         username           your username if you CPAN server wants one
         wait_list          arrayref to a wait server to try (See CPAN::WAIT)
         wget               path to external prg
         yaml_load_code     enable YAML code deserialisation via CPAN::DeferredCode
         yaml_module        which module to use to read/write YAML files

       You can set and query each of these options interactively
       in the cpan shell with the "o conf" or the "o conf init"
       command as specified below.

       "o conf <scalar option>"
         prints the current value of the scalar option

       "o conf <scalar option> <value>"
         Sets the value of the scalar option to value

       "o conf <list option>"
         prints the current value of the list option in
         MakeMaker's neatvalue format.

       "o conf <list option> [shift|pop]"
         shifts or pops the array in the list option variable



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       "o conf <list option> [unshift|push|splice] <list>"
         works like the corresponding perl commands.

       interactive editing: o conf init [MATCH|LIST]
         Runs an interactive configuration dialog for matching
         variables.  Without argument runs the dialog over all
         supported config variables.  To specify a MATCH the
         argument must be enclosed by slashes.

         Examples:

           o conf init ftp_passive ftp_proxy
           o conf init /color/

         Note: this method of setting config variables often
         provides more explanation about the functioning of a
         variable than the manpage.

   CPAN::anycwd($path): Note on config variable getcwd
       CPAN.pm changes the current working directory often and
       needs to determine its own current working directory. By
       default it uses Cwd::cwd, but if for some reason this
       doesn't work on your system, configure alternatives
       according to the following table:

       cwd Calls Cwd::cwd

       getcwd
           Calls Cwd::getcwd

       fastcwd
           Calls Cwd::fastcwd

       backtickcwd
           Calls the external command cwd.

   Note on the format of the urllist parameter
       urllist parameters are URLs according to RFC 1738. We do a
       little guessing if your URL is not compliant, but if you
       have problems with "file" URLs, please try the correct
       format. Either:

           file://localhost/whatever/ftp/pub/CPAN/

       or

           file:///home/ftp/pub/CPAN/

   The urllist parameter has CD-ROM support
       The "urllist" parameter of the configuration table
       contains a list of URLs used for downloading. If the list
       contains any "file" URLs, CPAN always tries there first.
       This feature is disabled for index files. So the
       recommendation for the owner of a CD-ROM with CPAN



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       contents is: include your local, possibly outdated CD-ROM
       as a "file" URL at the end of urllist, e.g.

         o conf urllist push file://localhost/CDROM/CPAN

       CPAN.pm will then fetch the index files from one of the
       CPAN sites that come at the beginning of urllist. It will
       later check for each module to see whether there is a
       local copy of the most recent version.

       Another peculiarity of urllist is that the site that we
       could successfully fetch the last file from automatically
       gets a preference token and is tried as the first site for
       the next request. So if you add a new site at runtime it
       may happen that the previously preferred site will be
       tried another time. This means that if you want to
       disallow a site for the next transfer, it must be
       explicitly removed from urllist.

   Maintaining the urllist parameter
       If you have YAML.pm (or some other YAML module configured
       in "yaml_module") installed, CPAN.pm collects a few
       statistical data about recent downloads. You can view the
       statistics with the "hosts" command or inspect them
       directly by looking into the "FTPstats.yml" file in your
       "cpan_home" directory.

       To get some interesting statistics, it is recommended that
       "randomize_urllist" be set; this introduces some amount of
       randomness into the URL selection.

   The "requires" and "build_requires" dependency declarations
       Since CPAN.pm version 1.88_51 modules declared as
       "build_requires" by a distribution are treated differently
       depending on the config variable
       "build_requires_install_policy". By setting
       "build_requires_install_policy" to "no", such a module is
       not installed. It is only built and tested, and then kept
       in the list of tested but uninstalled modules. As such, it
       is available during the build of the dependent module by
       integrating the path to the "blib/arch" and "blib/lib"
       directories in the environment variable PERL5LIB. If
       "build_requires_install_policy" is set ti "yes", then both
       modules declared as "requires" and those declared as
       "build_requires" are treated alike. By setting to
       "ask/yes" or "ask/no", CPAN.pm asks the user and sets the
       default accordingly.

   Configuration for individual distributions (Distroprefs)
       (Note: This feature has been introduced in CPAN.pm 1.8854
       and is still considered beta quality)

       Distributions on CPAN usually behave according to what we
       call the CPAN mantra. Or since the advent of Module::Build



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       we should talk about two mantras:

           perl Makefile.PL     perl Build.PL
           make                 ./Build
           make test            ./Build test
           make install         ./Build install

       But some modules cannot be built with this mantra. They
       try to get some extra data from the user via the
       environment, extra arguments, or interactively--thus
       disturbing the installation of large bundles like
       Phalanx100 or modules with many dependencies like Plagger.

       The distroprefs system of "CPAN.pm" addresses this problem
       by allowing the user to specify extra informations and
       recipes in YAML files to either

       o   pass additional arguments to one of the four commands,

       o   set environment variables

       o   instantiate an Expect object that reads from the
           console, waits for some regular expressions and enters
           some answers

       o   temporarily override assorted "CPAN.pm" configuration
           variables

       o   specify dependencies the original maintainer forgot

       o   disable the installation of an object altogether

       See the YAML and Data::Dumper files that come with the
       "CPAN.pm" distribution in the "distroprefs/" directory for
       examples.

   Filenames
       The YAML files themselves must have the ".yml" extension;
       all other files are ignored (for two exceptions see
       Fallback Data::Dumper and Storable below). The containing
       directory can be specified in "CPAN.pm" in the "prefs_dir"
       config variable. Try "o conf init prefs_dir" in the CPAN
       shell to set and activate the distroprefs system.

       Every YAML file may contain arbitrary documents according
       to the YAML specification, and every document is treated
       as an entity that can specify the treatment of a single
       distribution.

       Filenames can be picked arbitrarily; "CPAN.pm" always
       reads all files (in alphabetical order) and takes the key
       "match" (see below in Language Specs) as a hashref
       containing match criteria that determine if the current
       distribution matches the YAML document or not.



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   Fallback Data::Dumper and Storable
       If neither your configured "yaml_module" nor YAML.pm is
       installed, CPAN.pm falls back to using Data::Dumper and
       Storable and looks for files with the extensions ".dd" or
       ".st" in the "prefs_dir" directory. These files are
       expected to contain one or more hashrefs.  For
       Data::Dumper generated files, this is expected to be done
       with by defining $VAR1, $VAR2, etc. The YAML shell would
       produce these with the command

           ysh < somefile.yml > somefile.dd

       For Storable files the rule is that they must be
       constructed such that "Storable::retrieve(file)" returns
       an array reference and the array elements represent one
       distropref object each. The conversion from YAML would
       look like so:

           perl -MYAML=LoadFile -MStorable=nstore -e '
               @y=LoadFile(shift);
               nstore(\@y, shift)' somefile.yml somefile.st

       In bootstrapping situations it is usually sufficient to
       translate only a few YAML files to Data::Dumper for
       crucial modules like "YAML::Syck", "YAML.pm" and
       "Expect.pm". If you prefer Storable over Data::Dumper,
       remember to pull out a Storable version that writes an
       older format than all the other Storable versions that
       will need to read them.

   Blueprint
       The following example contains all supported keywords and
       structures with the exception of "eexpect" which can be
       used instead of "expect".

         ---
         comment: "Demo"
         match:
           module: "Dancing::Queen"
           distribution: "^CHACHACHA/Dancing-"
           not_distribution: "\.zip$"
           perl: "/usr/local/cariba-perl/bin/perl"
           perlconfig:
             archname: "freebsd"
             not_cc: "gcc"
           env:
             DANCING_FLOOR: "Shubiduh"
         disabled: 1
         cpanconfig:
           make: gmake
         pl:
           args:
             - "--somearg=specialcase"




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           env: {}

           expect:
             - "Which is your favorite fruit"
             - "apple\n"

         make:
           args:
             - all
             - extra-all

           env: {}

           expect: []

           commendline: "echo SKIPPING make"

         test:
           args: []

           env: {}

           expect: []

         install:
           args: []

           env:
             WANT_TO_INSTALL: YES

           expect:
             - "Do you really want to install"
             - "y\n"

         patches:
           - "ABCDE/Fedcba-3.14-ABCDE-01.patch"

         depends:
           configure_requires:
             LWP: 5.8
           build_requires:
             Test::Exception: 0.25
           requires:
             Spiffy: 0.30

   Language Specs
       Every YAML document represents a single hash reference.
       The valid keys in this hash are as follows:

       comment [scalar]
           A comment

       cpanconfig [hash]
           Temporarily override assorted "CPAN.pm" configuration



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           variables.

           Supported are: "build_requires_install_policy",
           "check_sigs", "make", "make_install_make_command",
           "prefer_installer", "test_report". Please report as a
           bug when you need another one supported.

       depends [hash] *** EXPERIMENTAL FEATURE ***
           All three types, namely "configure_requires",
           "build_requires", and "requires" are supported in the
           way specified in the META.yml specification. The
           current implementation merges the specified
           dependencies with those declared by the package
           maintainer. In a future implementation this may be
           changed to override the original declaration.

       disabled [boolean]
           Specifies that this distribution shall not be
           processed at all.

       features [array] *** EXPERIMENTAL FEATURE ***
           Experimental implementation to deal with
           optional_features from META.yml. Still needs
           coordination with installer software and currently
           works only for META.yml declaring "dynamic_config=0".
           Use with caution.

       goto [string]
           The canonical name of a delegate distribution to
           install instead. Useful when a new version, although
           it tests OK itself, breaks something else or a
           developer release or a fork is already uploaded that
           is better than the last released version.

       install [hash]
           Processing instructions for the "make install" or
           "./Build install" phase of the CPAN mantra. See below
           under Processing Instructions.

       make [hash]
           Processing instructions for the "make" or "./Build"
           phase of the CPAN mantra. See below under Processing
           Instructions.

       match [hash]
           A hashref with one or more of the keys "distribution",
           "modules", "perl", "perlconfig", and "env" that
           specify whether a document is targeted at a specific
           CPAN distribution or installation.  Keys prefixed with
           "not_" negates the corresponding match.

           The corresponding values are interpreted as regular
           expressions. The "distribution" related one will be
           matched against the canonical distribution name, e.g.



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           "AUTHOR/Foo-Bar-3.14.tar.gz".

           The "module" related one will be matched against all
           modules contained in the distribution until one module
           matches.

           The "perl" related one will be matched against $^X
           (but with the absolute path).

           The value associated with "perlconfig" is itself a
           hashref that is matched against corresponding values
           in the %Config::Config hash living in the "Config.pm"
           module.  Keys prefixed with "not_" negates the
           corresponding match.

           The value associated with "env" is itself a hashref
           that is matched against corresponding values in the
           %ENV hash.  Keys prefixed with "not_" negates the
           corresponding match.

           If more than one restriction of "module",
           "distribution", etc. is specified, the results of the
           separately computed match values must all match. If
           so, the hashref represented by the YAML document is
           returned as the preference structure for the current
           distribution.

       patches [array]
           An array of patches on CPAN or on the local disk to be
           applied in order via an external patch program. If the
           value for the "-p" parameter is 0 or 1 is determined
           by reading the patch beforehand. The path to each
           patch is either an absolute path on the local
           filesystem or relative to a patch directory specified
           in the "patches_dir" configuration variable or in the
           format of a canonical distroname. For examples please
           consult the distroprefs/ directory in the CPAN.pm
           distribution (these examples are not installed by
           default).

           Note: if the "applypatch" program is installed and
           "CPAN::Config" knows about it and a patch is written
           by the "makepatch" program, then "CPAN.pm" lets
           "applypatch" apply the patch. Both "makepatch" and
           "applypatch" are available from CPAN in the
           "JV/makepatch-*" distribution.

       pl [hash]
           Processing instructions for the "perl Makefile.PL" or
           "perl Build.PL" phase of the CPAN mantra. See below
           under Processing Instructions.

       test [hash]
           Processing instructions for the "make test" or



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           "./Build test" phase of the CPAN mantra. See below
           under Processing Instructions.

   Processing Instructions
       args [array]
           Arguments to be added to the command line

       commandline
           A full commandline to run via "system()".  During
           execution, the environment variable PERL is set to $^X
           (but with an absolute path). If "commandline" is
           specified, "args" is not used.

       eexpect [hash]
           Extended "expect". This is a hash reference with four
           allowed keys, "mode", "timeout", "reuse", and "talk".

           "mode" may have the values "deterministic" for the
           case where all questions come in the order written
           down and "anyorder" for the case where the questions
           may come in any order. The default mode is
           "deterministic".

           "timeout" denotes a timeout in seconds. Floating-point
           timeouts are OK. With "mode=deterministic", the
           timeout denotes the timeout per question; with
           "mode=anyorder" it denotes the timeout per byte
           received from the stream or questions.

           "talk" is a reference to an array that contains
           alternating questions and answers. Questions are
           regular expressions and answers are literal strings.
           The Expect module watches the stream from the
           execution of the external program ("perl Makefile.PL",
           "perl Build.PL", "make", etc.).

           For "mode=deterministic", the CPAN.pm injects the
           corresponding answer as soon as the stream matches the
           regular expression.

           For "mode=anyorder" CPAN.pm answers a question as soon
           as the timeout is reached for the next byte in the
           input stream. In this mode you can use the "reuse"
           parameter to decide what will happen with a question-
           answer pair after it has been used. In the default
           case (reuse=0) it is removed from the array, avoiding
           being used again accidentally. If you want to answer
           the question "Do you really want to do that" several
           times, then it must be included in the array at least
           as often as you want this answer to be given. Setting
           the parameter "reuse" to 1 makes this repetition
           unnecessary.





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       env [hash]
           Environment variables to be set during the command

       expect [array]
           "expect: <array>" is a short notation for

           eexpect:
               mode: deterministic
               timeout: 15
               talk: <array>

   Schema verification with "Kwalify"
       If you have the "Kwalify" module installed (which is part
       of the Bundle::CPANxxl), then all your distroprefs files
       are checked for syntactic correctness.

   Example Distroprefs Files
       "CPAN.pm" comes with a collection of example YAML files.
       Note that these are really just examples and should not be
       used without care because they cannot fit everybody's
       purpose. After all, the authors of the packages that ask
       questions had a need to ask, so you should watch their
       questions and adjust the examples to your environment and
       your needs. You have been warned:-)

PROGRAMMER'S INTERFACE
       If you do not enter the shell, shell commands are
       available both as methods ("CPAN::Shell->install(...)")
       and as functions in the calling package ("install(...)").
       Before calling low-level commands, it makes sense to
       initialize components of CPAN you need, e.g.:

         CPAN::HandleConfig->load;
         CPAN::Shell::setup_output;
         CPAN::Index->reload;

       High-level commands do such initializations automatically.

       There's currently only one class that has a stable
       interface - CPAN::Shell. All commands that are available
       in the CPAN shell are methods of the class CPAN::Shell.
       Each of the commands that produce listings of modules
       ("r", "autobundle", "u") also return a list of the IDs of
       all modules within the list.

       expand($type,@things)
         The IDs of all objects available within a program are
         strings that can be expanded to the corresponding real
         objects with the "CPAN::Shell->expand("Module",@things)"
         method. Expand returns a list of CPAN::Module objects
         according to the @things arguments given. In scalar
         context, it returns only the first element of the list.





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       expandany(@things)
         Like expand, but returns objects of the appropriate
         type, i.e.  CPAN::Bundle objects for bundles,
         CPAN::Module objects for modules, and CPAN::Distribution
         objects for distributions. Note: it does not expand to
         CPAN::Author objects.

       Programming Examples
         This enables the programmer to do operations that
         combine functionalities that are available in the shell.

             # install everything that is outdated on my disk:
             perl -MCPAN -e 'CPAN::Shell->install(CPAN::Shell->r)'

             # install my favorite programs if necessary:
             for $mod (qw(Net::FTP Digest::SHA Data::Dumper)) {
                 CPAN::Shell->install($mod);
             }

             # list all modules on my disk that have no VERSION number
             for $mod (CPAN::Shell->expand("Module","/./")) {
                 next unless $mod->inst_file;
                 # MakeMaker convention for undefined $VERSION:
                 next unless $mod->inst_version eq "undef";
                 print "No VERSION in ", $mod->id, "\n";
             }

             # find out which distribution on CPAN contains a module:
             print CPAN::Shell->expand("Module","Apache::Constants")->cpan_file

         Or if you want to schedule a cron job to watch CPAN, you
         could list all modules that need updating. First a quick
         and dirty way:

             perl -e 'use CPAN; CPAN::Shell->r;'

         If you don't want any output should all modules be up to
         date, parse the output of above command for the regular
         expression "/modules are up to date/" and decide to mail
         the output only if it doesn't match.

         If you prefer to do it more in a programmerish style in
         one single process, something like this may better suit
         you:

           # list all modules on my disk that have newer versions on CPAN
           for $mod (CPAN::Shell->expand("Module","/./")) {
             next unless $mod->inst_file;
             next if $mod->uptodate;
             printf "Module %s is installed as %s, could be updated to %s from CPAN\n",
                 $mod->id, $mod->inst_version, $mod->cpan_version;
           }

         If that gives too much output every day, you may want to



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         watch only for three modules. You can write

           for $mod (CPAN::Shell->expand("Module","/Apache|LWP|CGI/")) {

         as the first line instead. Or you can combine some of
         the above tricks:

           # watch only for a new mod_perl module
           $mod = CPAN::Shell->expand("Module","mod_perl");
           exit if $mod->uptodate;
           # new mod_perl arrived, let me know all update recommendations
           CPAN::Shell->r;

   Methods in the other Classes
       CPAN::Author::as_glimpse()
           Returns a one-line description of the author

       CPAN::Author::as_string()
           Returns a multi-line description of the author

       CPAN::Author::email()
           Returns the author's email address

       CPAN::Author::fullname()
           Returns the author's name

       CPAN::Author::name()
           An alias for fullname

       CPAN::Bundle::as_glimpse()
           Returns a one-line description of the bundle

       CPAN::Bundle::as_string()
           Returns a multi-line description of the bundle

       CPAN::Bundle::clean()
           Recursively runs the "clean" method on all items
           contained in the bundle.

       CPAN::Bundle::contains()
           Returns a list of objects' IDs contained in a bundle.
           The associated objects may be bundles, modules or
           distributions.

       CPAN::Bundle::force($method,@args)
           Forces CPAN to perform a task that it normally would
           have refused to do. Force takes as arguments a method
           name to be called and any number of additional
           arguments that should be passed to the called method.
           The internals of the object get the needed changes so
           that CPAN.pm does not refuse to take the action. The
           "force" is passed recursively to all contained
           objects. See also the section above on the "force" and
           the "fforce" pragma.



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       CPAN::Bundle::get()
           Recursively runs the "get" method on all items
           contained in the bundle

       CPAN::Bundle::inst_file()
           Returns the highest installed version of the bundle in
           either @INC or "$CPAN::Config-"{cpan_home}>. Note that
           this is different from CPAN::Module::inst_file.

       CPAN::Bundle::inst_version()
           Like CPAN::Bundle::inst_file, but returns the $VERSION

       CPAN::Bundle::uptodate()
           Returns 1 if the bundle itself and all its members are
           uptodate.

       CPAN::Bundle::install()
           Recursively runs the "install" method on all items
           contained in the bundle

       CPAN::Bundle::make()
           Recursively runs the "make" method on all items
           contained in the bundle

       CPAN::Bundle::readme()
           Recursively runs the "readme" method on all items
           contained in the bundle

       CPAN::Bundle::test()
           Recursively runs the "test" method on all items
           contained in the bundle

       CPAN::Distribution::as_glimpse()
           Returns a one-line description of the distribution

       CPAN::Distribution::as_string()
           Returns a multi-line description of the distribution

       CPAN::Distribution::author
           Returns the CPAN::Author object of the maintainer who
           uploaded this distribution

       CPAN::Distribution::pretty_id()
           Returns a string of the form "AUTHORID/TARBALL", where
           AUTHORID is the author's PAUSE ID and TARBALL is the
           distribution filename.

       CPAN::Distribution::base_id()
           Returns the distribution filename without any archive
           suffix.  E.g "Foo-Bar-0.01"

       CPAN::Distribution::clean()
           Changes to the directory where the distribution has
           been unpacked and runs "make clean" there.



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       CPAN::Distribution::containsmods()
           Returns a list of IDs of modules contained in a
           distribution file.  Works only for distributions
           listed in the 02packages.details.txt.gz file. This
           typically means that just most recent version of a
           distribution is covered.

       CPAN::Distribution::cvs_import()
           Changes to the directory where the distribution has
           been unpacked and runs something like

               cvs -d $cvs_root import -m $cvs_log $cvs_dir $userid v$version

           there.

       CPAN::Distribution::dir()
           Returns the directory into which this distribution has
           been unpacked.

       CPAN::Distribution::force($method,@args)
           Forces CPAN to perform a task that it normally would
           have refused to do. Force takes as arguments a method
           name to be called and any number of additional
           arguments that should be passed to the called method.
           The internals of the object get the needed changes so
           that CPAN.pm does not refuse to take the action. See
           also the section above on the "force" and the "fforce"
           pragma.

       CPAN::Distribution::get()
           Downloads the distribution from CPAN and unpacks it.
           Does nothing if the distribution has already been
           downloaded and unpacked within the current session.

       CPAN::Distribution::install()
           Changes to the directory where the distribution has
           been unpacked and runs the external command "make
           install" there. If "make" has not yet been run, it
           will be run first. A "make test" is issued in any case
           and if this fails, the install is cancelled. The
           cancellation can be avoided by letting "force" run the
           "install" for you.

           This install method only has the power to install the
           distribution if there are no dependencies in the way.
           To install an object along with all its dependencies,
           use CPAN::Shell->install.

           Note that install() gives no meaningful return value.
           See uptodate().

       CPAN::Distribution::install_tested()
           Install all distributions that have tested sucessfully
           but not yet installed. See also "is_tested".



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       CPAN::Distribution::isa_perl()
           Returns 1 if this distribution file seems to be a perl
           distribution.  Normally this is derived from the file
           name only, but the index from CPAN can contain a hint
           to achieve a return value of true for other filenames
           too.

       CPAN::Distribution::look()
           Changes to the directory where the distribution has
           been unpacked and opens a subshell there. Exiting the
           subshell returns.

       CPAN::Distribution::make()
           First runs the "get" method to make sure the
           distribution is downloaded and unpacked. Changes to
           the directory where the distribution has been unpacked
           and runs the external commands "perl Makefile.PL" or
           "perl Build.PL" and "make" there.

       CPAN::Distribution::perldoc()
           Downloads the pod documentation of the file associated
           with a distribution (in HTML format) and runs it
           through the external command lynx specified in
           "$CPAN::Config-"{lynx}>. If lynx isn't available, it
           converts it to plain text with the external command
           html2text and runs it through the pager specified in
           "$CPAN::Config-"{pager}>

       CPAN::Distribution::prefs()
           Returns the hash reference from the first matching
           YAML file that the user has deposited in the
           "prefs_dir/" directory. The first succeeding match
           wins. The files in the "prefs_dir/" are processed
           alphabetically, and the canonical distroname (e.g.
           AUTHOR/Foo-Bar-3.14.tar.gz) is matched against the
           regular expressions stored in the
           $root->{match}{distribution} attribute value.
           Additionally all module names contained in a
           distribution are matched against the regular
           expressions in the $root->{match}{module} attribute
           value. The two match values are ANDed together. Each
           of the two attributes are optional.

       CPAN::Distribution::prereq_pm()
           Returns the hash reference that has been announced by
           a distribution as the "requires" and "build_requires"
           elements. These can be declared either by the
           "META.yml" (if authoritative) or can be deposited
           after the run of "Build.PL" in the file
           "./_build/prereqs" or after the run of "Makfile.PL"
           written as the "PREREQ_PM" hash in a comment in the
           produced "Makefile". Note: this method only works
           after an attempt has been made to "make" the
           distribution. Returns undef otherwise.



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       CPAN::Distribution::readme()
           Downloads the README file associated with a
           distribution and runs it through the pager specified
           in "$CPAN::Config-"{pager}>.

       CPAN::Distribution::reports()
           Downloads report data for this distribution from
           www.cpantesters.org and displays a subset of them.

       CPAN::Distribution::read_yaml()
           Returns the content of the META.yml of this distro as
           a hashref. Note: works only after an attempt has been
           made to "make" the distribution.  Returns undef
           otherwise. Also returns undef if the content of
           META.yml is not authoritative. (The rules about what
           exactly makes the content authoritative are still in
           flux.)

       CPAN::Distribution::test()
           Changes to the directory where the distribution has
           been unpacked and runs "make test" there.

       CPAN::Distribution::uptodate()
           Returns 1 if all the modules contained in the
           distribution are uptodate. Relies on containsmods.

       CPAN::Index::force_reload()
           Forces a reload of all indices.

       CPAN::Index::reload()
           Reloads all indices if they have not been read for
           more than "$CPAN::Config-"{index_expire}> days.

       CPAN::InfoObj::dump()
           CPAN::Author, CPAN::Bundle, CPAN::Module, and
           CPAN::Distribution inherit this method. It prints the
           data structure associated with an object. Useful for
           debugging. Note: the data structure is considered
           internal and thus subject to change without notice.

       CPAN::Module::as_glimpse()
           Returns a one-line description of the module in four
           columns: The first column contains the word "Module",
           the second column consists of one character: an equals
           sign if this module is already installed and uptodate,
           a less-than sign if this module is installed but can
           be upgraded, and a space if the module is not
           installed. The third column is the name of the module
           and the fourth column gives maintainer or distribution
           information.

       CPAN::Module::as_string()
           Returns a multi-line description of the module




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       CPAN::Module::clean()
           Runs a clean on the distribution associated with this
           module.

       CPAN::Module::cpan_file()
           Returns the filename on CPAN that is associated with
           the module.

       CPAN::Module::cpan_version()
           Returns the latest version of this module available on
           CPAN.

       CPAN::Module::cvs_import()
           Runs a cvs_import on the distribution associated with
           this module.

       CPAN::Module::description()
           Returns a 44 character description of this module.
           Only available for modules listed in The Module List
           (CPAN/modules/00modlist.long.html or
           00modlist.long.txt.gz)

       CPAN::Module::distribution()
           Returns the CPAN::Distribution object that contains
           the current version of this module.

       CPAN::Module::dslip_status()
           Returns a hash reference. The keys of the hash are the
           letters "D", "S", "L", "I", and <P>, for development
           status, support level, language, interface and public
           licence respectively. The data for the DSLIP status
           are collected by pause.perl.org when authors register
           their namespaces. The values of the 5 hash elements
           are one-character words whose meaning is described in
           the table below. There are also 5 hash elements "DV",
           "SV", "LV", "IV", and <PV> that carry a more verbose
           value of the 5 status variables.

           Where the 'DSLIP' characters have the following
           meanings:

             D - Development Stage  (Note: *NO IMPLIED TIMESCALES*):
               i   - Idea, listed to gain consensus or as a placeholder
               c   - under construction but pre-alpha (not yet released)
               a/b - Alpha/Beta testing
               R   - Released
               M   - Mature (no rigorous definition)
               S   - Standard, supplied with Perl 5

             S - Support Level:
               m   - Mailing-list
               d   - Developer
               u   - Usenet newsgroup comp.lang.perl.modules
               n   - None known, try comp.lang.perl.modules



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               a   - abandoned; volunteers welcome to take over maintainance

             L - Language Used:
               p   - Perl-only, no compiler needed, should be platform independent
               c   - C and perl, a C compiler will be needed
               h   - Hybrid, written in perl with optional C code, no compiler needed
               +   - C++ and perl, a C++ compiler will be needed
               o   - perl and another language other than C or C++

             I - Interface Style
               f   - plain Functions, no references used
               h   - hybrid, object and function interfaces available
               n   - no interface at all (huh?)
               r   - some use of unblessed References or ties
               O   - Object oriented using blessed references and/or inheritance

             P - Public License
               p   - Standard-Perl: user may choose between GPL and Artistic
               g   - GPL: GNU General Public License
               l   - LGPL: "GNU Lesser General Public License" (previously known as
                     "GNU Library General Public License")
               b   - BSD: The BSD License
               a   - Artistic license alone
               2   - Artistic license 2.0 or later
               o   - open source: appoved by www.opensource.org
               d   - allows distribution without restrictions
               r   - restricted distribtion
               n   - no license at all

       CPAN::Module::force($method,@args)
           Forces CPAN to perform a task it would normally refuse
           to do. Force takes as arguments a method name to be
           invoked and any number of additional arguments to pass
           that method.  The internals of the object get the
           needed changes so that CPAN.pm does not refuse to take
           the action. See also the section above on the "force"
           and the "fforce" pragma.

       CPAN::Module::get()
           Runs a get on the distribution associated with this
           module.

       CPAN::Module::inst_file()
           Returns the filename of the module found in @INC. The
           first file found is reported, just as perl itself
           stops searching @INC once it finds a module.

       CPAN::Module::available_file()
           Returns the filename of the module found in PERL5LIB
           or @INC. The first file found is reported. The
           advantage of this method over "inst_file" is that
           modules that have been tested but not yet installed
           are included because PERL5LIB keeps track of tested
           modules.



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       CPAN::Module::inst_version()
           Returns the version number of the installed module in
           readable format.

       CPAN::Module::available_version()
           Returns the version number of the available module in
           readable format.

       CPAN::Module::install()
           Runs an "install" on the distribution associated with
           this module.

       CPAN::Module::look()
           Changes to the directory where the distribution
           associated with this module has been unpacked and
           opens a subshell there. Exiting the subshell returns.

       CPAN::Module::make()
           Runs a "make" on the distribution associated with this
           module.

       CPAN::Module::manpage_headline()
           If module is installed, peeks into the module's
           manpage, reads the headline, and returns it. Moreover,
           if the module has been downloaded within this session,
           does the equivalent on the downloaded module even if
           it hasn't been installed yet.

       CPAN::Module::perldoc()
           Runs a "perldoc" on this module.

       CPAN::Module::readme()
           Runs a "readme" on the distribution associated with
           this module.

       CPAN::Module::reports()
           Calls the reports() method on the associated
           distribution object.

       CPAN::Module::test()
           Runs a "test" on the distribution associated with this
           module.

       CPAN::Module::uptodate()
           Returns 1 if the module is installed and up-to-date.

       CPAN::Module::userid()
           Returns the author's ID of the module.

   Cache Manager
       Currently the cache manager only keeps track of the build
       directory ($CPAN::Config->{build_dir}). It is a simple
       FIFO mechanism that deletes complete directories below
       "build_dir" as soon as the size of all directories there



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       gets bigger than $CPAN::Config->{build_cache} (in MB). The
       contents of this cache may be used for later re-
       installations that you intend to do manually, but will
       never be trusted by CPAN itself. This is due to the fact
       that the user might use these directories for building
       modules on different architectures.

       There is another directory
       ($CPAN::Config->{keep_source_where}) where the original
       distribution files are kept. This directory is not covered
       by the cache manager and must be controlled by the user.
       If you choose to have the same directory as build_dir and
       as keep_source_where directory, then your sources will be
       deleted with the same fifo mechanism.

   Bundles
       A bundle is just a perl module in the namespace Bundle::
       that does not define any functions or methods. It usually
       only contains documentation.

       It starts like a perl module with a package declaration
       and a $VERSION variable. After that the pod section looks
       like any other pod with the only difference being that one
       special pod section exists starting with (verbatim):

           =head1 CONTENTS

       In this pod section each line obeys the format

               Module_Name [Version_String] [- optional text]

       The only required part is the first field, the name of a
       module (e.g. Foo::Bar, ie. not the name of the
       distribution file). The rest of the line is optional. The
       comment part is delimited by a dash just as in the man
       page header.

       The distribution of a bundle should follow the same
       convention as other distributions.

       Bundles are treated specially in the CPAN package. If you
       say 'install Bundle::Tkkit' (assuming such a bundle
       exists), CPAN will install all the modules in the CONTENTS
       section of the pod. You can install your own Bundles
       locally by placing a conformant Bundle file somewhere into
       your @INC path. The autobundle() command which is
       available in the shell interface does that for you by
       including all currently installed modules in a snapshot
       bundle file.

PREREQUISITES
       If you have a local mirror of CPAN and can access all
       files with "file:" URLs, then you only need a perl later
       than perl5.003 to run this module. Otherwise Net::FTP is



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       strongly recommended. LWP may be required for non-UNIX
       systems, or if your nearest CPAN site is associated with a
       URL that is not "ftp:".

       If you have neither Net::FTP nor LWP, there is a fallback
       mechanism implemented for an external ftp command or for
       an external lynx command.

UTILITIES
   Finding packages and VERSION
       This module presumes that all packages on CPAN

       o declare their $VERSION variable in an easy to parse
         manner. This prerequisite can hardly be relaxed because
         it consumes far too much memory to load all packages
         into the running program just to determine the $VERSION
         variable. Currently all programs that are dealing with
         version use something like this

             perl -MExtUtils::MakeMaker -le \
                 'print MM->parse_version(shift)' filename

         If you are author of a package and wonder if your
         $VERSION can be parsed, please try the above method.

       o come as compressed or gzipped tarfiles or as zip files
         and contain a "Makefile.PL" or "Build.PL" (well, we try
         to handle a bit more, but with little enthusiasm).

   Debugging
       Debugging this module is more than a bit complex due to
       interference from the software producing the indices on
       CPAN, the mirroring process on CPAN, packaging,
       configuration, synchronicity, and even (gasp!) due to bugs
       within the CPAN.pm module itself.

       For debugging the code of CPAN.pm itself in interactive
       mode, some debugging aid can be turned on for most
       packages within CPAN.pm with one of

       o debug package...
         sets debug mode for packages.

       o debug -package...
         unsets debug mode for packages.

       o debug all
         turns debugging on for all packages.

       o debug number

       which sets the debugging packages directly. Note that "o
       debug 0" turns debugging off.




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       What seems a successful strategy is the combination of
       "reload cpan" and the debugging switches. Add a new debug
       statement while running in the shell and then issue a
       "reload cpan" and see the new debugging messages
       immediately without losing the current context.

       "o debug" without an argument lists the valid package
       names and the current set of packages in debugging mode.
       "o debug" has built-in completion support.

       For debugging of CPAN data there is the "dump" command
       which takes the same arguments as make/test/install and
       outputs each object's Data::Dumper dump. If an argument
       looks like a perl variable and contains one of "$", "@" or
       "%", it is eval()ed and fed to Data::Dumper directly.

   Floppy, Zip, Offline Mode
       CPAN.pm works nicely without network access, too. If you
       maintain machines that are not networked at all, you
       should consider working with "file:" URLs. You'll have to
       collect your modules somewhere first. So you might use
       CPAN.pm to put together all you need on a networked
       machine. Then copy the $CPAN::Config->{keep_source_where}
       (but not $CPAN::Config->{build_dir}) directory on a
       floppy. This floppy is kind of a personal CPAN. CPAN.pm on
       the non-networked machines works nicely with this floppy.
       See also below the paragraph about CD-ROM support.

   Basic Utilities for Programmers
       has_inst($module)
         Returns true if the module is installed. Used to load
         all modules into the running CPAN.pm that are considered
         optional. The config variable "dontload_list" intercepts
         the "has_inst()" call such that an optional module is
         not loaded despite being available. For example, the
         following command will prevent "YAML.pm" from being
         loaded:

             cpan> o conf dontload_list push YAML

         See the source for details.

       has_usable($module)
         Returns true if the module is installed and in a usable
         state. Only useful for a handful of modules that are
         used internally. See the source for details.

       instance($module)
         The constructor for all the singletons used to represent
         modules, distributions, authors, and bundles. If the
         object already exists, this method returns the object;
         otherwise, it calls the constructor.





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SECURITY
       There's no strong security layer in CPAN.pm. CPAN.pm helps
       you to install foreign, unmasked, unsigned code on your
       machine. We compare to a checksum that comes from the net
       just as the distribution file itself. But we try to make
       it easy to add security on demand:

   Cryptographically signed modules
       Since release 1.77, CPAN.pm has been able to verify
       cryptographically signed module distributions using
       Module::Signature.  The CPAN modules can be signed by
       their authors, thus giving more security.  The simple
       unsigned MD5 checksums that were used before by CPAN
       protect mainly against accidental file corruption.

       You will need to have Module::Signature installed, which
       in turn requires that you have at least one of
       Crypt::OpenPGP module or the command-line gpg tool
       installed.

       You will also need to be able to connect over the Internet
       to the public keyservers, like pgp.mit.edu, and their port
       11731 (the HKP protocol).

       The configuration parameter check_sigs is there to turn
       signature checking on or off.

EXPORT
       Most functions in package CPAN are exported by default.
       The reason for this is that the primary use is intended
       for the cpan shell or for one-liners.

ENVIRONMENT
       When the CPAN shell enters a subshell via the look
       command, it sets the environment CPAN_SHELL_LEVEL to 1, or
       increments that variable if it is already set.

       When CPAN runs, it sets the environment variable
       PERL5_CPAN_IS_RUNNING to the ID of the running process. It
       also sets PERL5_CPANPLUS_IS_RUNNING to prevent runaway
       processes which could happen with older versions of
       Module::Install.

       When running "perl Makefile.PL", the environment variable
       "PERL5_CPAN_IS_EXECUTING" is set to the full path of the
       "Makefile.PL" that is being executed. This prevents
       runaway processes with newer versions of Module::Install.

       When the config variable ftp_passive is set, all downloads
       will be run with the environment variable FTP_PASSIVE set
       to this value. This is in general a good idea as it
       influences both Net::FTP and LWP based connections. The
       same effect can be achieved by starting the cpan shell
       with this environment variable set. For Net::FTP alone,



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       one can also always set passive mode by running libnetcfg.

POPULATE AN INSTALLATION WITH LOTS OF MODULES
       Populating a freshly installed perl with one's favorite
       modules is pretty easy if you maintain a private bundle
       definition file. To get a useful blueprint of a bundle
       definition file, the command autobundle can be used on the
       CPAN shell command line. This command writes a bundle
       definition file for all modules installed for the current
       perl interpreter. It's recommended to run this command
       once only, and from then on maintain the file manually
       under a private name, say Bundle/my_bundle.pm. With a
       clever bundle file you can then simply say

           cpan> install Bundle::my_bundle

       then answer a few questions and go out for coffee
       (possibly even in a different city).

       Maintaining a bundle definition file means keeping track
       of two things: dependencies and interactivity. CPAN.pm
       sometimes fails on calculating dependencies because not
       all modules define all MakeMaker attributes correctly, so
       a bundle definition file should specify prerequisites as
       early as possible. On the other hand, it's annoying that
       so many distributions need some interactive configuring.
       So what you can try to accomplish in your private bundle
       file is to have the packages that need to be configured
       early in the file and the gentle ones later, so you can go
       out for cofeee after a few minutes and leave CPAN.pm to
       churn away untended.

WORKING WITH CPAN.pm BEHIND FIREWALLS
       Thanks to Graham Barr for contributing the following
       paragraphs about the interaction between perl, and various
       firewall configurations. For further information on
       firewalls, it is recommended to consult the documentation
       that comes with the ncftp program. If you are unable to go
       through the firewall with a simple Perl setup, it is
       likely that you can configure ncftp so that it works
       through your firewall.

   Three basic types of firewalls
       Firewalls can be categorized into three basic types.

       http firewall
           This is when the firewall machine runs a web server,
           and to access the outside world, you must do so via
           that web server. If you set environment variables like
           http_proxy or ftp_proxy to values beginning with
           http://, or in your web browser you've proxy
           information set, then you know you are running behind
           an http firewall.




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           To access servers outside these types of firewalls
           with perl (even for ftp), you need LWP.

       ftp firewall
           This where the firewall machine runs an ftp server.
           This kind of firewall will only let you access ftp
           servers outside the firewall.  This is usually done by
           connecting to the firewall with ftp, then entering a
           username like "user@outside.host.com".

           To access servers outside these type of firewalls with
           perl, you need Net::FTP.

       One-way visibility
           One-way visibility means these firewalls try to make
           themselves invisible to users inside the firewall. An
           FTP data connection is normally created by sending
           your IP address to the remote server and then
           listening for the return connection. But the remote
           server will not be able to connect to you because of
           the firewall. For these types of firewall, FTP
           connections need to be done in a passive mode.

           There are two that I can think off.

           SOCKS
               If you are using a SOCKS firewall, you will need
               to compile perl and link it with the SOCKS
               library.  This is what is normally called a
               'socksified' perl. With this executable you will
               be able to connect to servers outside the firewall
               as if it were not there.

           IP Masquerade
               This is when the firewall implemented in the
               kernel (via NAT, or networking address
               translation), it allows you to hide a complete
               network behind one IP address. With this firewall
               no special compiling is needed as you can access
               hosts directly.

               For accessing ftp servers behind such firewalls
               you usually need to set the environment variable
               "FTP_PASSIVE" or the config variable ftp_passive
               to a true value.

   Configuring lynx or ncftp for going through a firewall
       If you can go through your firewall with e.g. lynx,
       presumably with a command such as

           /usr/local/bin/lynx -pscott:tiger

       then you would configure CPAN.pm with the command




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           o conf lynx "/usr/local/bin/lynx -pscott:tiger"

       That's all. Similarly for ncftp or ftp, you would
       configure something like

           o conf ncftp "/usr/bin/ncftp -f /home/scott/ncftplogin.cfg"

       Your mileage may vary...

FAQ
       1)  I installed a new version of module X but CPAN keeps
           saying, I have the old version installed

           Probably you do have the old version installed. This
           can happen if a module installs itself into a
           different directory in the @INC path than it was
           previously installed. This is not really a CPAN.pm
           problem, you would have the same problem when
           installing the module manually. The easiest way to
           prevent this behaviour is to add the argument
           "UNINST=1" to the "make install" call, and that is why
           many people add this argument permanently by
           configuring

             o conf make_install_arg UNINST=1

       2)  So why is UNINST=1 not the default?

           Because there are people who have their precise
           expectations about who may install where in the @INC
           path and who uses which @INC array. In fine tuned
           environments "UNINST=1" can cause damage.

       3)  I want to clean up my mess, and install a new perl
           along with all modules I have. How do I go about it?

           Run the autobundle command for your old perl and
           optionally rename the resulting bundle file (e.g.
           Bundle/mybundle.pm), install the new perl with the
           Configure option prefix, e.g.

               ./Configure -Dprefix=/usr/local/perl-5.6.78.9

           Install the bundle file you produced in the first step
           with something like

               cpan> install Bundle::mybundle

           and you're done.

       4)  When I install bundles or multiple modules with one
           command there is too much output to keep track of.

           You may want to configure something like



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             o conf make_arg "| tee -ai /root/.cpan/logs/make.out"
             o conf make_install_arg "| tee -ai /root/.cpan/logs/make_install.out"

           so that STDOUT is captured in a file for later
           inspection.

       5)  I am not root, how can I install a module in a
           personal directory?

           First of all, you will want to use your own
           configuration, not the one that your root user
           installed. If you do not have permission to write in
           the cpan directory that root has configured, you will
           be asked if you want to create your own config.
           Answering "yes" will bring you into CPAN's
           configuration stage, using the system config for all
           defaults except things that have to do with CPAN's
           work directory, saving your choices to your
           MyConfig.pm file.

           You can also manually initiate this process with the
           following command:

               % perl -MCPAN -e 'mkmyconfig'

           or by running

               mkmyconfig

           from the CPAN shell.

           You will most probably also want to configure
           something like this:

             o conf makepl_arg "LIB=~/myperl/lib \
                               INSTALLMAN1DIR=~/myperl/man/man1 \
                               INSTALLMAN3DIR=~/myperl/man/man3 \
                               INSTALLSCRIPT=~/myperl/bin \
                               INSTALLBIN=~/myperl/bin"

           and then the equivalent command for Module::Build,
           which is

             o conf mbuildpl_arg "--lib=~/myperl/lib \
                               --installman1dir=~/myperl/man/man1 \
                               --installman3dir=~/myperl/man/man3 \
                               --installscript=~/myperl/bin \
                               --installbin=~/myperl/bin"

           You can make this setting permanent like all "o conf"
           settings with "o conf commit" or by setting
           "auto_commit" beforehand.

           You will have to add ~/myperl/man to the MANPATH



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           environment variable and also tell your perl programs
           to look into ~/myperl/lib, e.g. by including

             use lib "$ENV{HOME}/myperl/lib";

           or setting the PERL5LIB environment variable.

           While we're speaking about $ENV{HOME}, it might be
           worth mentioning, that for Windows we use the
           File::HomeDir module that provides an equivalent to
           the concept of the home directory on Unix.

           Another thing you should bear in mind is that the
           UNINST parameter can be dangerous when you are
           installing into a private area because you might
           accidentally remove modules that other people depend
           on that are not using the private area.

       6)  How to get a package, unwrap it, and make a change
           before building it?

           Have a look at the "look" (!) command.

       7)  I installed a Bundle and had a couple of fails. When I
           retried, everything resolved nicely. Can this be fixed
           to work on first try?

           The reason for this is that CPAN does not know the
           dependencies of all modules when it starts out. To
           decide about the additional items to install, it just
           uses data found in the META.yml file or the generated
           Makefile. An undetected missing piece breaks the
           process. But it may well be that your Bundle installs
           some prerequisite later than some depending item and
           thus your second try is able to resolve everything.
           Please note, CPAN.pm does not know the dependency tree
           in advance and cannot sort the queue of things to
           install in a topologically correct order. It resolves
           perfectly well if all modules declare the
           prerequisites correctly with the PREREQ_PM attribute
           to MakeMaker or the "requires" stanza of
           Module::Build. For bundles which fail and you need to
           install often, it is recommended to sort the Bundle
           definition file manually.

       8)  In our intranet, we have many modules for internal
           use. How can I integrate these modules with CPAN.pm
           but without uploading the modules to CPAN?

           Have a look at the CPAN::Site module.

       9)  When I run CPAN's shell, I get an error message about
           things in my "/etc/inputrc" (or "~/.inputrc") file.




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           These are readline issues and can only be fixed by
           studying readline configuration on your architecture
           and adjusting the referenced file accordingly. Please
           make a backup of the "/etc/inputrc" or "~/.inputrc"
           and edit them. Quite often harmless changes like
           uppercasing or lowercasing some arguments solves the
           problem.

       10) Some authors have strange characters in their names.

           Internally CPAN.pm uses the UTF-8 charset. If your
           terminal is expecting ISO-8859-1 charset, a converter
           can be activated by setting term_is_latin to a true
           value in your config file. One way of doing so would
           be

               cpan> o conf term_is_latin 1

           If other charset support is needed, please file a
           bugreport against CPAN.pm at rt.cpan.org and describe
           your needs. Maybe we can extend the support or maybe
           UTF-8 terminals become widely available.

           Note: this config variable is deprecated and will be
           removed in a future version of CPAN.pm. It will be
           replaced with the conventions around the family of
           $LANG and $LC_* environment variables.

       11) When an install fails for some reason and then I
           correct the error condition and retry, CPAN.pm refuses
           to install the module, saying "Already tried without
           success".

           Use the force pragma like so

             force install Foo::Bar

           Or you can use

             look Foo::Bar

           and then "make install" directly in the subshell.

       12) How do I install a "DEVELOPER RELEASE" of a module?

           By default, CPAN will install the latest non-developer
           release of a module. If you want to install a dev
           release, you have to specify the partial path starting
           with the author id to the tarball you wish to install,
           like so:

               cpan> install KWILLIAMS/Module-Build-0.27_07.tar.gz

           Note that you can use the "ls" command to get this



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           path listed.

       13) How do I install a module and all its dependencies
           from the commandline, without being prompted for
           anything, despite my CPAN configuration (or lack
           thereof)?

           CPAN uses ExtUtils::MakeMaker's prompt() function to
           ask its questions, so if you set the
           PERL_MM_USE_DEFAULT environment variable, you
           shouldn't be asked any questions at all (assuming the
           modules you are installing are nice about obeying that
           variable as well):

               % PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install My::Module'

       14) How do I create a Module::Build based Build.PL derived
           from an ExtUtils::MakeMaker focused Makefile.PL?

           http://search.cpan.org/search?query=Module::Build::Convert

           http://www.refcnt.org/papers/module-build-convert

       15) I'm frequently irritated with the CPAN shell's
           inability to help me select a good mirror.

           The urllist config parameter is yours. You can add and
           remove sites at will. You should find out which sites
           have the best uptodateness, bandwidth, reliability,
           etc. and are topologically close to you. Some people
           prefer fast downloads, others uptodateness, others
           reliability.  You decide which to try in which order.

           Henk P. Penning maintains a site that collects data
           about CPAN sites:

             http://www.cs.uu.nl/people/henkp/mirmon/cpan.html

           Also, feel free to play with experimental features.
           Run

             o conf init randomize_urllist ftpstats_period ftpstats_size

           and choose your favorite parameters. After a few
           downloads running the "hosts" command will probably
           assist you in choosing the best mirror sites.

       16) Why do I get asked the same questions every time I
           start the shell?

           You can make your configuration changes permanent by
           calling the command "o conf commit". Alternatively set
           the "auto_commit" variable to true by running "o conf
           init auto_commit" and answering the following question



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           with yes.

       17) Older versions of CPAN.pm had the original root
           directory of all tarballs in the build directory. Now
           there are always random characters appended to these
           directory names. Why was this done?

           The random characters are provided by File::Temp and
           ensure that each module's individual build directory
           is unique. This makes running CPAN.pm in concurrent
           processes simultaneously safe.

       18) Speaking of the build directory. Do I have to clean it
           up myself?

           You have the choice to set the config variable
           "scan_cache" to "never". Then you must clean it up
           yourself. The other possible value, "atstart" only
           cleans up the build directory when you start the CPAN
           shell. If you never start up the CPAN shell, you
           probably also have to clean up the build directory
           yourself.

COMPATIBILITY
   OLD PERL VERSIONS
       CPAN.pm is regularly tested to run under 5.004, 5.005, and
       assorted newer versions. It is getting more and more
       difficult to get the minimal prerequisites working on
       older perls. It is close to impossible to get the whole
       Bundle::CPAN working there. If you're in the position to
       have only these old versions, be advised that CPAN is
       designed to work fine without the Bundle::CPAN installed.

       To get things going, note that
       GBARR/Scalar-List-Utils-1.18.tar.gz is compatible with
       ancient perls and that File::Temp is listed as a
       prerequisite but CPAN has reasonable workarounds if it is
       missing.

   CPANPLUS
       This module and its competitor, the CPANPLUS module, are
       both much cooler than the other. CPAN.pm is older.
       CPANPLUS was designed to be more modular, but it was never
       intended to be compatible with CPAN.pm.

SECURITY ADVICE
       This software enables you to upgrade software on your
       computer and so is inherently dangerous because the newly
       installed software may contain bugs and may alter the way
       your computer works or even make it unusable. Please
       consider backing up your data before every upgrade.

BUGS
       Please report bugs via <http://rt.cpan.org/>



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       Before submitting a bug, please make sure that the
       traditional method of building a Perl module package from
       a shell by following the installation instructions of that
       package still works in your environment.

AUTHOR
       Andreas Koenig "<andk@cpan.org>"

LICENSE
       This program is free software; you can redistribute it
       and/or modify it under the same terms as Perl itself.

       See <http://www.perl.com/perl/misc/Artistic.html>

TRANSLATIONS
       Kawai,Takanori provides a Japanese translation of this
       manpage at
       <http://homepage3.nifty.com/hippo2000/perltips/CPAN.htm>

SEE ALSO
       cpan, CPAN::Nox, CPAN::Version




































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