CentOS 7.0 - man page for cpan (centos section 3pm)

Linux & Unix Commands - Search Man Pages

Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


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

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 LWP,
       HTTP::Tiny, Net::FTP 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.

       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 "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. Argument processing is as follows:

	   known module name in format Foo/Bar.pm   module
	   other embedded slash 		    distribution
	     - with trailing slash dot		    directory
	   enclosing slashes			    regexp
	   known module name in format Foo::Bar     module

	 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"). If an argument is enclosed in slashes it is treated as a
	 regular expression: it is expanded and if the result is a single object (distribution,
	 bundle or module), this object is processed.

	 Example:

	     install Dummy::Perl		   # installs the module
	     install AUXXX/Dummy-Perl-3.14.tar.gz  # installs that distribution
	     install /Dummy-Perl-3.14/		   # same if the regexp is unambiguous

	 "get" downloads a distribution file and untars or unzips 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
	 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:

	   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. A SIGALRM is also used
	 during module version parsing, and is controlled by "version_timeout".

   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. Duplicates of each distribution are suppressed.  The name of the
       bundle file is based on the current date and a counter.

       Return value: path to the written file.

   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.

   r [Module|/Regexp/]...
       scans current perl installation for modules that have a newer version available on CPAN
       and provides a list of them. If called without argument, all potential upgrades are
       listed; if called with arguments the list is filtered to the modules and regexps given as
       arguments.

       The listing looks something like this:

	 Package namespace	   installed	latest	in CPAN file
	 CPAN			     1.94_64	1.9600	ANDK/CPAN-1.9600.tar.gz
	 CPAN::Reporter 	      1.1801	1.1902	DAGOLDEN/CPAN-Reporter-1.1902.tar.gz
	 YAML				0.70	  0.73	INGY/YAML-0.73.tar.gz
	 YAML::Syck			1.14	  1.17	AVAR/YAML-Syck-1.17.tar.gz
	 YAML::Tiny			1.44	  1.50	ADAMK/YAML-Tiny-1.50.tar.gz
	 CGI				3.43	  3.55	MARKSTOS/CGI.pm-3.55.tar.gz
	 Module::Build::YAML		1.40	  1.41	DAGOLDEN/Module-Build-0.3800.tar.gz
	 TAP::Parser::Result::YAML	3.22	  3.23	ANDYA/Test-Harness-3.23.tar.gz
	 YAML::XS			0.34	  0.35	INGY/YAML-LibYAML-0.35.tar.gz

       It suppresses duplicates in the column "in CPAN file" such that distributions with many
       upgradeable modules are listed only once.

       Note that the list is not sorted.

   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 (a.k.a. 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 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|/Regexp/]...
       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

	   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.

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 regexp 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 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
	 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 environment variable 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
	 patches_dir	    local directory containing patch files
	 perl5lib_verbosity verbosity level for PERL5LIB additions
	 prefer_external_tar
			    per default all untar operations are done with
			    Archive::Tar; by setting this variable to true
			    the external tar command is used if available
	 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')
			    For 'follow', also sets PERL_AUTOINSTALL and
			    PERL_EXTUTILS_AUTOINSTALL for "--defaultdeps" if
			    not already set
	 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', 'atexit' 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
	 version_timeout    stops version parsing after this many seconds.
			    Default is 15 secs. Set to 0 to disable.
	 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

       "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 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 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.

   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"

	   env: {}

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

	 make:
	   args:
	     - all
	     - extra-all

	   env: {}

	   expect: []

	   commandline: "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 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.
	   "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 distro name. 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 "./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".

	   You must install the "Expect" module to use "eexpect". CPAN.pm does not install it for
	   you.

	   "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.

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

       expect [array]
	   You must install the "Expect" module to use "expect". CPAN.pm does not install it for
	   you.

	   "expect: <array>" is a short notation for this "eexpect":

		   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. The arguments
       on the commandline are passed as arguments to the method.

       So if you take for example the shell command

	 notest install A B C

       the actually executed command is

	 CPAN::Shell->notest("install","A","B","C");

       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.

       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 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.

       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 up-to-date.

       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.

       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 successfully but not yet installed. See
	   also "is_tested".

       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 distro name (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.

       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 up-to-date. 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 up-to-date, 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

       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
	       a   - abandoned; volunteers welcome to take over maintenance

	     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: approved by www.opensource.org
	       d   - allows distribution without restrictions
	       r   - restricted distribution
	       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.

       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 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, i.e. 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
       The CPAN program is trying to depend on as little as possible so the user can use it in
       hostile environment. It works better the more goodies the environment provides. For
       example if you try in the CPAN shell

	 install Bundle::CPAN

       or

	 install Bundle::CPANxxl

       you will find the shell more convenient than the bare shell before.

       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 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.

       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.

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 key servers, 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, 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 coffee 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.

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

       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

	   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

	     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?

	   As of CPAN 1.9463, if you do not have permission to write the default perl library
	   directories, CPAN's configuration process will ask you whether you want to bootstrap
	   <local::lib>, which makes keeping a personal perl library directory easy.

	   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.

	   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 bug report 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 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/dist/Module-Build-Convert/

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

	   CPAN can now help you select a "good" mirror, based on which ones have the lowest
	   'ping' round-trip times.  From the shell, use the command 'o conf init urllist' and
	   allow CPAN to automatically select mirrors for you.

	   Beyond that help, the urllist config parameter is yours. You can add and remove sites
	   at will. You should find out which sites have the best up-to-dateness, bandwidth,
	   reliability, etc. and are topologically close to you. Some people prefer fast
	   downloads, others up-to-dateness, 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 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 values, "atstart" and "atexit" clean up the
	   build directory when you start or exit the CPAN shell, respectively. 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.

   CPANMINUS
       In the year 2010 App::cpanminus was launched as a new approach to a cpan shell with a
       considerably smaller footprint. Very cool stuff.

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/>

       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 a very old version of this manpage at
       <http://homepage3.nifty.com/hippo2000/perltips/CPAN.htm>

SEE ALSO
       Many people enter the CPAN shell by running the cpan utility program which is installed in
       the same directory as perl itself. So if you have this directory in your PATH variable (or
       some equivalent in your operating system) then typing "cpan" in a console window will work
       for you as well. Above that the utility provides several commandline shortcuts.

perl v5.16.3				    2013-03-04					CPAN(3pm)
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 02:16 PM.

Unix & Linux Forums Content Copyright©1993-2018. All Rights Reserved.
×
UNIX.COM Login
Username:
Password:  
Show Password





Not a Forum Member?
Forgot Password?