NAME CPAN - query, download and build perl modules from CPAN sites SYNOPSIS Interactive mode: perl -MCPAN -e shell; Batch mode: use CPAN; autobundle, bundle, bundles, expand, install, make, test ALPHA ALERT The interface of this package is not yet stable. Parts of it may still change. This is especially true for the programming interface. The interactive "shell" interface is already rather well established. DESCRIPTION The CPAN module is designed to automate the building and installing of perl modules and extensions including the searching and fetching from the net. Modules are fetched from one or more of the mirrored CPAN (Comprehensive Perl Archive Network) sites and unpacked in a dedicated directory. The CPAN module also supports the concept of named and versioned 'bundles' of modules. Bundles simplify the handling of sets of related modules. See BUNDLES below. The package contains a session manager and a cache manager. There is no status retained between sessions. 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 in a simple FIFO style. Interactive Mode The interactive mode is entered by running perl -MCPAN -e shell which puts you into a readline interface. You will have most fun if you install Term::ReadKey and Term::ReadLine to enjoy both history and completion. Once you are on the command line, type 'h' and the rest should be self-explanatory. CPAN::Shell The commands that are available in the shell interface are methods in the package CPAN::Shell. If you enter the shell command, all your input is split on whitespace, the first word is being interpreted as the method to be called and the rest of the words are treated as arguments to this method. If you do not enter the shell, most of the available shell commands are both available as methods (`CPAN::Shell- >install(...)') and as functions in the calling package (`install(...)'). 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 $CPAN::Config->{build_cache} (in MB). There is another directory ($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, that one 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 (eg. 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. The bundle() function in the CPAN module simply parses the module that defines the bundle and returns the module names that are listed in the described CONTENTS section. 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. autobundle autobundle() writes a bundle file into the directory $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. Pragma: force Normally CPAN keeps track of what it has done within the current session and doesn't try to build a package a second time regardless if it succeeded or not. The force command takes as first argument the method to invoke (currently: make, test, or install) and executes the command from scratch. Example: cpan> install OpenGL OpenGL is up to date. cpan> force install OpenGL Running make OpenGL-0.4/ OpenGL-0.4/COPYRIGHT [...] CONFIGURATION When the CPAN module is installed a site wide configuration file is created as CPAN/Config.pm. The default values defined there can be overridden in another configuration file: CPAN/MyConfig.pm. You can store this file in $HOME/.cpan/CPAN/MyConfig.pm if you want, because $HOME/.cpan is added to the search path of the CPAN module before the use() or require() statements. Currently the following keys in the hash reference $CPAN::Config are defined: build_cache size of cache for directories to build modules build_dir locally accessible directory to build modules index_expire after how many days refetch index files cpan_home local directory reserved for this package gzip location of external program gzip inhibit_startup_message if true, does not print the startup message keep_source keep the source in a local directory? keep_source_where where keep the source (if we do) make location of external program make make_arg arguments that should always be passed to 'make' make_install_arg same as make_arg for 'make install' makepl_arg arguments passed to 'perl Makefile.PL' pager location of external program more (or any pager) tar location of external program tar unzip location of external program unzip urllist arrayref to nearby CPAN sites (or equivalent locations) You can set and query each of these options interactively in the cpan shell with the command set defined within the `o conf' command: o conf prints the current value of the *scalar option* o conf Sets the value of the *scalar option* to *value* o conf prints the current value of the *list option* in MakeMaker's neatvalue format. o conf [shift|pop] shifts or pops the array in the *list option* variable o conf [unshift|push|splice] works like the corresponding perl commands. Whitespace is used to determine the arguments. SECURITY There's no security layer in the alpha version of CPAN.pm. CPAN.pm helps you to install foreign, unmasked, unsigned code on your machine. It's not different than when you do that on your own, but you should be warned now. EXPORT Most functions in package CPAN are exported per default. The reason for this is that the primary use is intended for the cpan shell or for oneliners. Debugging The debugging of this module is pretty difficult, because we have interferences of the software producing the indices on CPAN, of the mirroring process on CPAN, of packaging, of configuration, and of bugs within CPAN.pm. In interactive mode you can try "o debug" which will list options for debugging the various parts of the package. The output may not be very useful for you as it's just a byproduct of my own testing, but if you have an idea which part of the package may have a bug, it's certainly worth to give it a try and send me more specific output. You should know that "o debug" has built-in completion support. Prerequisites If you have a local mirror of CPAN and can access all files with "file:" URLs, then you only need perl5.003 to run this module. Otherwise you need Net::FTP intalled. LWP may be required for non-UNIX systems. This module presumes that all packages on CPAN * declare their $VERSION variable in an easy to parse manner. This prerequisite can hardly be relaxed because it consumes by far too much memory to load all packages into the running program just to determine the $VERSION variable . Currently all programs that are dealing with VERSION use something like this (requires MakeMaker-5.38, but don't bother if you don't have it): perl -MExtUtils::MakeMaker -le \ 'print MM->parse_version($ARGV[0])' filename If you are author of a package and wonder if your VERSION can be parsed, please try the above method. * come as compressed or gzipped tarfiles or as zip files (well we try to handle a bit more, but without much enthusiasm). AUTHOR Andreas König SEE ALSO perl(1)