[ic] V0.3 of cpan_local_install

Mike Heins mikeh@minivend.com
Sun, 15 Oct 2000 17:14:02 -0400

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While testing 4.5.8 candidate on BSD, I tried installing 
on a blank perl. No dice -- I think I may have it usable by
everyone now.

Akopia, Inc., 131 Willow Lane, Floor 2, Oxford, OH  45056
phone +1.513.523.7621 fax 7501 <heins@akopia.com>

In character, in manners, in style, in all things, the supreme excellence
is simplicity. -- Longfellow

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Content-Disposition: attachment; filename=cpan_local_install


## This is here because Perl 5.005 installations may try to re-install
## a whole perl if you run this! If you want to try it, then

use lib './lib';
use lib '../lib';
use lib "$ENV{HOME}/.cpan";
use Getopt::Std;


eval {
	require 5.6.0;

use vars qw/$opt_f $opt_d $opt_h/;
my $prog = $0;
$prog =~ s:.*/::;

$::USAGE = <<EOF;
usage: $prog [-f] [-d interchange_root] [module1 module2 module_n]

[module] defaults to Bundle::Interchange.


    -f    Force install for Perl 5.005
    -d    Set interchange root directory (default current)


if($opt_h) {
	warn $USAGE;
	exit 2;

if($@) {

	require 5.005;
	if(! $opt_f) {
		my $args = join " ", @ARGV;
		print <<EOF;
Perl 5.005 installations may try to re-install a whole perl if you run this! If
you want to try it, then rerun with a -f flag, i.e.

	$0 -f $args


use Cwd;
use File::Spec;

use strict;

my $libdir = $opt_d || $opt_d || '';

my @mods_to_get = @ARGV;

if(! @mods_to_get) {
	push @mods_to_get, 'Bundle::Interchange';

if(! $libdir) {
	my @possible = grep -f $_, qw/minivend.cfg interchange.cfg interchange.cfg.dist/;
	if(@possible) {
		$libdir = cwd() if -d 'lib';

$libdir =~ s:(^|/)lib$::;

if(! File::Spec->file_name_is_absolute($libdir) ) {
	$libdir = File::Spec->catfile(cwd(), $libdir);

unshift @INC, $libdir, "$libdir/lib";

$ENV{PERL5LIB} = join ":", @INC;

use CPAN;

eval { 	
		require CPAN::MyConfig
		require CPAN::Config;

my $showprompt;
if($@) {
	CPAN::get 'Bundle::Interchange';
	$showprompt = 1;

# See if we have the CPAN module
eval { 	
		die "Don't try this at home with Windows.\n" if $^O =~ /win32/i;

if($@) {
	die "Can't do cpan_local_install: $@\n";

sub my_prompt {
    my($pr) = shift || '? ';
    my($def) = shift;

    print $pr;
    print "[$def] " if $def;
    chomp($ans = <STDIN>);
    $ans ? $ans : $def;

print <<EOF if $showprompt;

We can go and get optional modules that help Interchange work a
bit better and faster. At least we can if you are connected
to the Internet and have one of the following on your machine:

		Perl LWP libraries
		Perl Net::FTP library
		ncftp (a nice FTP program)
		lynx  (the text-based web browser)

In case you were wondering, CPAN is a worldwide network of
over 100 FTP sites which maintain the latest Perl software.
If you don't know a URL to use, you can try:


If you have never used CPAN before, you may want to reply NO.
Interchange should work anyway -- it just won't be quite as easy
to build the demo catalogs.

If you have errors during the process, don't worry. Either
just continue on or stop the program and try again, replying
No when prompted for CPAN.


for my $module (@mods_to_get) {
	#my $prompt = "Get $module? [yes] ";
	#my $ask = my_prompt($prompt);
	#exit 2 if $ask =~ /^\s*n/i;
	$CPAN::Config->{makepl_arg} = "INSTALLPRIVLIB=$libdir/lib INSTALLARCHLIB=$libdir/lib INSTALLSITELIB=$libdir/lib INSTALLMAN1DIR=none INSTALLMAN3DIR=none INSTALLSITEARCH=$libdir/lib INSTALLDIRS=perl";
	$CPAN::Config->{keep_source_where} = "$libdir/src"
		unless -w $CPAN::Config->{keep_source_where};
	$CPAN::Config->{cpan_home} = "$libdir/src"
		unless -w $CPAN::Config->{cpan_home};
	$CPAN::Config->{build_dir} = "$libdir/src"
		unless -w $CPAN::Config->{build_dir};
	my $incstring = join " ", @INC;
	print <<EOF;


.0::CPAN(3)    User Contributed Perl Documentation    .0::CPAN(3)

       CPAN - query, download and build perl modules from CPAN

       Interactive mode:

	 perl -MCPAN -e shell;

       Batch mode:

	 use CPAN;

	 autobundle, clean, install, make, recompile, test

       The CPAN module is designed to automate the make and
       install of perl modules and extensions. It includes some
       searching capabilities and knows how to use Net::FTP or
       LWP (or lynx or an external ftp client) to fetch the raw
       data 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 according to a simple
       FIFO mechanism.

       For extended searching capabilities there's a plugin for
       CPAN available, the CPAN::WAIT manpage. `CPAN::WAIT' is a
       full-text search engine that indexes all documents
       available in CPAN authors directories. If `CPAN::WAIT' is
       installed on your system, the interactive shell of
       <CPAN.pm> will enable the `wq', `wr', `wd', `wl', and `wh'
       commands which send queries to the WAIT server that has
       been configured for your installation.

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

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       Interactive Mode

       The interactive mode is entered by running

	   perl -MCPAN -e shell

       which puts you into a readline interface. You will have
       the most fun if you install Term::ReadKey and
       Term::ReadLine to enjoy both history and command

       Once you are on the command line, type 'h' and the rest
       should be self-explanatory.

       The most common uses of the interactive modes are

       Searching for authors, bundles, distribution files and
	 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 you pass to these commands are either strings
	 exactly matching the identification string of an object
	 or regular expressions that are then matched case-
	 insensitively against various attributes of the objects.
	 The parser recognizes a regular expression only if you
	 enclose it between two slashes.

	 The principle is that the number of found objects
	 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 we find more than
	 one, we display each object with the terse method

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

	 Any `make' or `test' are run unconditionally. An

	   install <distribution_file>

	 also is run unconditionally. But for

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	   install <module>

	 CPAN checks if an install is actually needed for it and
	 prints module up to date in the case that the
	 distribution file containing the module doesn't need to
	 be updated.

	 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 if it succeeded or not. The
	 `force' command takes as a first argument the method to
	 invoke (currently: `make', `test', or `install') and
	 executes the command from scratch.


	     cpan> install OpenGL
	     OpenGL is up to date.
	     cpan> force install OpenGL
	     Running make

	 A `clean' command results in a

	   make clean

	 being executed within the distribution file's working

       get, readme, look module or distribution
	 `get' downloads a distribution file without further
	 action. `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.

	 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 a SIGPIPE. If the user sets
	 inactivity_timeout, a SIGALRM is used during the run of
	 the `perl Makefile.PL' subprocess.

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       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 by the
       Text::ParseWords::shellwords() routine which acts like
       most shells do. 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. Continuation lines are
       supported if a line ends with a literal backslash.


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


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

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

       The four `CPAN::*' Classes: Author, Bundle, Module,

       Although it may be considered internal, the class
       hierarchy does matter for both users and programmer.
       CPAN.pm deals with above mentioned four classes, and all
       those classes share a set of methods. A 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):

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		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 visible
       version number), so the really hottest and newest
       distribution file 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

	   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

       Programmer's interface

       If you do not enter the shell, the available shell
       commands are both available as methods
       (`CPAN::Shell->install(...)') and as functions in the
       calling package (`install(...)').

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

	 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 only returns the first element of the list.

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       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 MD5 Data::Dumper)){
		 my $obj = CPAN::Shell->expand('Module',$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 write a cronjob to watch The 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 to get any output if all modules are
	 up to date, you can 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 programmer style in one
	 single process, maybe something like this suites 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 you too much output every day, you maybe
	 only want to watch 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

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	 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

       Methods in the four Classes

       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.


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

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

	       =head1 CONTENTS

       In this pod section each line obeys the format

	       Module_Name [Version_String] [- optional text]

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

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       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.


       If you have a local mirror of CPAN and can access all
       files with "file:" URLs, then you only need a perl better
       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 an
       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.

       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 (well, we try to handle a bit
	 more, but without much enthusiasm).


       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

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       packaging, of configuration, of synchronicity, 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
       by-product of my own testing, but if you have an idea
       which part of the package may have a bug, it's sometimes
       worth to give it a try and send me more specific output.
       You should know that "o debug" has built-in completion

       Floppy, Zip, Offline Mode

       CPAN.pm works nicely without network too. If you maintain
       machines that are not networked at all, you should
       consider working with file: URLs. Of course, you 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.

       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:

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	 build_cache	    size of cache for directories to build modules
	 build_dir	    locally accessible directory to build modules
	 index_expire	    after this many days refetch index files
	 cpan_home	    local directory reserved for this package
	 dontload_hash	    anonymous hash: modules in the keys will not be
			    loaded by the CPAN::has_inst() routine
	 gzip		    location of external program gzip
	 inactivity_timeout breaks interactive Makefile.PLs after this
			    many seconds inactivity. Set to 0 to never break.
			    if true, does not print the startup message
	 keep_source_where  directory in which to keep the source (if we do)
	 make		    location of external make program
	 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)
			    what to do if you are missing module prerequisites
			    ('follow' automatically, 'ask' me, or 'ignore')
	 scan_cache	    controls scanning of cache ('atstart' or 'never')
	 tar		    location of external program tar
	 unzip		    location of external program unzip
	 urllist	    arrayref to nearby CPAN sites (or equivalent locations)
	 wait_list	    arrayref to a wait server to try (See CPAN::WAIT)
	 ftp_proxy,	 }  the three usual variables for configuring
	   http_proxy,	 }  proxy requests. Both as CPAN::Config variables
	   no_proxy	 }  and as environment variables configurable.

       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 <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.

       Note on urllist parameter's format

       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

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       format. Either:




       urllist parameter has CD-ROM support

       The `urllist' parameter of the configuration table
       contains a list of URLs that are to be used for
       downloading. If the list contains any `file' URLs, CPAN
       always tries to get files from 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 if 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.

       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. If somebody has
       managed to tamper with the distribution file, they may
       have as well tampered with the CHECKSUMS file. Future
       development will go towards strong authentication.

       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.

       To populate a freshly installed perl with my favorite
       modules is pretty easiest by maintaining a private bundle
       definition file. To get a useful blueprint of a bundle

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       definition file, the command autobundle can be used on the
       CPAN shell command line. This command writes a bundle
       definition file for all modules that are installed for the
       currently running perl interpreter. It's recommended to
       run this command only once 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 then go out for a coffee.

       Maintaining a bundle definition file means to keep 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 a bit annoying
       that many distributions need some interactive configuring.
       So what I try to accomplish in my private bundle file is
       to have the packages that need to be configured early in
       the file and the gentle ones later, so I can go out after
       a few minutes and leave CPAN.pm unattained.

       Thanks to Graham Barr for contributing the following
       paragraphs about the interaction between perl, and various
       firewall configurations. For further informations 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 very
       likely that you can configure ncftp so that it works for
       your firewall.

       Three basic types of firewalls

       Firewalls can be categorized into three basic types.

       http firewall
	   This is where the firewall machine runs a web server
	   and to access the outside world you must do it via the
	   web server. If you set environment variables like
	   http_proxy or ftp_proxy to a values beginning with
	   http:// or in your web browser you have to set proxy
	   information then you know you are running a http

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

       ftp firewall
	   This where the firewall machine runs a ftp server.
	   This kind of firewall will only let you access ftp

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	   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 will need to use Net::FTP.

       One way visibility
	   I say one way visibility as these firewalls try to
	   make themselve look invisible to the users inside the
	   firewall. An FTP data connection is normally created
	   by sending the remote server your IP address and then
	   listening for the connection. But the remote server
	   will not be able to connect to you because of the
	   firewall. So for these types of firewall FTP
	   connections need to be done in a passive mode.

	   There are two that I can think off.

	       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
	       is not there.

	   IP Masquerade
	       This is the firewall implemented in the Linux
	       kernel, it allows you to hide a complete network
	       behind one IP address. With this firewall no
	       special compiling is need as you can access hosts

       Configuring lynx or ncftp for going throught the 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 milage may vary...


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

	     o conf make_install_arg UNINST=1

       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.

       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

       We should give coverage for all of the CPAN and not just
       the PAUSE part, right? In this discussion CPAN and PAUSE
       have become equal -- but they are not. PAUSE is authors/
       and modules/. CPAN is PAUSE plus the clpa/, doc/, misc/,
       ports/, src/, scripts/.

       Future development should be directed towards a better
       integration of the other parts.

       If a Makefile.PL requires special customization of
       libraries, prompts the user for special input, etc. then
       you may find CPAN is not able to build the distribution.
       In that case, you should attempt the traditional method of
       building a Perl module package from a shell.

       Andreas Koenig <andreas.koenig@anima.de>

       perl(1), CPAN:\fIs0:Nox(3)

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