How do I get a list of installed CPAN modules?

Question

Aside from trying

perldoc <module name>

individually for any CPAN module that takes my fancy or going through the file system and looking at the directories, I have no idea what modules we have installed.

What's the easiest way to just get a big list of every CPAN module installed? From the command line or otherwise.

Fjeld

I can suggest using the pmtools, especially pminst which accepts regular expressions. – Cindelyn

perl-pmtools is the good tools for you. – Unstudied

Do you want to know what modules are installed, or what distributions are installed? – Edentate

I found cpan -l to be useful for myself on windows. – Maximilianus

This might be useful: instmodsh – Gelya

Answer 1

This is answered in the Perl FAQ, the answer which can be quickly found with perldoc -q installed. In short, it comes down to using ExtUtils::Installed or using File::Find, variants of both of which have been covered previously in this thread.

You can also find the FAQ entry "How do I find which modules are installed on my system?" in perlfaq3. You can see a list of all FAQ answers by looking in perlfaq

Cryptanalysis

This gives so much more than the OP requested that it is virtually useless. – Nucleo

cpan -l is doing a recursive search of whatever directory I run it from. Is there any way to pass the ExtUtils::Installed constructor's skip_cwd option from that command line? – Arioso

The FAQ says to use cpan -l but that doesn't work on RHEL6, and /usr/bin/cpan -l throws the error Unknown option: l. – Abruption

$ perldoc perllocal | grep Module $ perldoc perllocal | grep -E 'VERSION|Module' – Trustful

use perldoc -t perllocal to get plain text output, otherwise grep may not work due to embedded ctrl characters – Solidstate

@Trustful perldoc perllocal | grep -E 'VERSION|Module > perlmods.txt - nice way of filtering the long readout, so I piped into a file – Inflated

Answer 2

perldoc perllocal

Edit: There's a (little) more info about it in the CPAN FAQ

Billyebilobate

Thanks for the link to the FAQ. Unfortunately not all the modules I know are installed are returning. Date::Calc doesn't even show up there. – Fjeld

I got No documentation found for "perllocal". – Benedikta

Answer 3

perldoc -q installed

claims that cpan -l will do the trick, however it's not working for me. The other option:

cpan -a

does spit out a nice list of installed packages and has the nice side effect of writing them to a file.

Diseuse

For the record, cpan -l works (or does for me with CPAN v2.05). cpan -a is indeed prettier. – Nitaniter

I just used cpan -l | grep packageName to find what I needed per the recommendation found in perldoc. – Mandarin

Answer 4

$ for M in `perldoc -t perllocal|grep Module |sed -e 's/^.*" //'`; do V=`perldoc -t perllocal|awk "/$M/{y=1;next}y" |grep VERSION |head -n 1`; printf "%30s %s\n" "$M" "$V"; done |sort
              Class::Inspector     *   "VERSION: 1.28"
                    Crypt::CBC     *   "VERSION: 2.33"
               Crypt::Rijndael     *   "VERSION: 1.11"
                    Data::Dump     *   "VERSION: 1.22"
                   DBD::Oracle     *   "VERSION: 1.68"
                           DBI     *   "VERSION: 1.630"
                   Digest::SHA     *   "VERSION: 5.92"
           ExtUtils::MakeMaker     *   "VERSION: 6.84"
                       install     *   "VERSION: 6.84"
               IO::SessionData     *   "VERSION: 1.03"
               IO::Socket::SSL     *   "VERSION: 2.016"
                          JSON     *   "VERSION: 2.90"
                  MIME::Base64     *   "VERSION: 3.14"
                  MIME::Base64     *   "VERSION: 3.14"
                   Mozilla::CA     *   "VERSION: 20141217"
                   Net::SSLeay     *   "VERSION: 1.68"
                        parent     *   "VERSION: 0.228"
                  REST::Client     *   "VERSION: 271"
                    SOAP::Lite     *   "VERSION: 1.08"
                  Task::Weaken     *   "VERSION: 1.04"
                 Term::ReadKey     *   "VERSION: 2.31"
                Test::Manifest     *   "VERSION: 1.23"
                  Test::Simple     *   "VERSION: 1.001002"
                  Text::CSV_XS     *   "VERSION: 1.16"
                     Try::Tiny     *   "VERSION: 0.22"
                   XML::LibXML     *   "VERSION: 2.0108"
         XML::NamespaceSupport     *   "VERSION: 1.11"
                XML::SAX::Base     *   "VERSION: 1.08"

Billyebilobate

this works nicely for those of us who don't have cpan installed. – Had

Really underrated answer. This also works for RHEL distributions. – Pantelegraph

I got: No documentation found for "perllocal". – Amusing

Took longer to run than I expected (about 20 seconds or so on my machine), but it worked flawlessly! Great answer. – Hypnogenesis

Answer 5

It's worth noting that perldoc perllocal will only report on modules installed via CPAN. If someone installs modules manually, it won't find them. Also, if you have multiple people installing modules and the perllocal.pod is under source control, people might resolve conflicts incorrectly and corrupt the list (this has happened here at work, for example).

Regrettably, the solution appears to be walking through @INC with File::Find or something similar. However, that doesn't just find the modules, it also finds related modules in a distribution. For example, it would report TAP::Harness and TAP::Parser in addition to the actual distribution name of Test::Harness (assuming you have version 3 or above). You could potentially match them up with distribution names and discard those names which don't match, but then you might be discarding locally built and installed modules.

I believe brian d foy's backpan indexing work is supposed to have code to hand it at .pm file and it will attempt to infer the distribution, but even this fails at times because what's in a package is not necessarily installed (see Devel::Cover::Inc for an example).

Denver

I don't think I need to pull out the BackPAN catalog guns for that one. Something like I do with Test::Prereq to collapse it by what distro it finds in 02packages might be enough. That is a little tricker than just listing the module files though, and the catalog isn't close to handling that yet. – Palacios

From a rudimentary test (doing a "make -n install" in some dirs I have laying around), the "make install" step of any MakeMaker-based module will update perllocal. It's not specific to installing via CPAN directly. – Procedure

I think Dist::Surveyor is still the best tool for answering the question "what distributions are installed in that library?". See this presentation for more details. There's an easy-to-use fatpacked version in the git repo. – Edentate

Answer 6

You can try ExtUtils-Installed, but that only looks in .packlists, so it may miss modules that people moved things into @INC by hand.

I wrote App-Module-Lister for a friend who wanted to do this as a CGI script on a non-shell web hosting account. You simple take the module file and upload it as a filename that your server will treat as a CGI script. It has no dependencies outside of the Standard Library. Use it as is or steal the code.

It outputs a list of the modules and their versions:

Tie::Cycle      1.15
Tie::IxHash     1.21
Tie::Toggle     1.07
Tie::ToObject   0.03
Time::CTime     99.062201
Time::DaysInMonth       99.1117
Time::Epoch     0.02
Time::Fuzzy     0.34
Time::JulianDay 2003.1125
Time::ParseDate 2006.0814
Time::Timezone  2006.0814

I've been meaning to add this as a feature to the cpan tool, so I'll do that too. [Time passes] And, now I have a -l switch in cpan. I have a few other things to do with it before I make a release, but it's in github. If you don't want to wait for that, you could just try the -a switch to create an autobundle, although that puts some Pod around the list.

Good luck;

Palacios

Answer 7

Here a script which would do the trick:

use ExtUtils::Installed;

my $inst = ExtUtils::Installed->new();
my @modules = $inst->modules();
foreach $module (@modules){
       print $module ." - ". $inst->version($module). "\n";
}

=head1 ABOUT

This scripts lists installed cpan modules using the ExtUtils modules

=head1 FORMAT

Prints each module in the following format
<name> - <version>

=cut

Pure

Under RHEL 6.9, this scrips only prints the following: Perl - 5.10.1 Modules are not listed. – Bushbuck

Answer 8

Try the following command

instmodsh

With l you will List all installed modules.

From man page:

A shell to examine installed modules.
A little interface to ExtUtils::Installed to examine installed modules, validate your packlists and even create a tarball from an installed module.

Quintillion

Simplest answer. Worked fine on our ancient Debian 6 server. – Inflated

Answer 9

I like to use the CPAN 'r' command for this. You can get into the CPAN shell with the old style:

sudo perl -MCPAN -e shell

or, on most newer systems, there is a 'cpan' command, so this command will get you to the shell:

sudo cpan

(You typically have to use 'sudo' to run it as root, or use 'su -' to become root before you run it, unless you have cpan set up to let you run it as a normal user, but install as root. If you don't have root on this machine, you can still use the CPAN shell to find out this information, but you won't be able to install modules, and you may have to go through a bit of setup the first time you run it.)

Then, once you're in the cpan shell, you can use the 'r' command to report all installed modules and their versions. So, at the "cpan>" prompt, type 'r'. This will list all installed modules and their versions. Use '?' to get some more help.

Jugular

actually 'r' gives you the reinstall recommendations - ie all the modules on your install that have a newer version of CPAN. Unless your install is very out of date this will not be a complete list. – Calathus

My 'r' always reports next to nothing because I upgrade compulsively. Which reminds me ... I haven't upgraded today, yet. – Mulkey

The -r recompiles stuff. To get a list, try -a or download the latest sources and play with the new -l switch, added for just this answer. :) – Palacios

Why the sudo here? It’s completely unnecessary. – Baumbaugh

note the difference between the '-r' commandline argument to 'cpan', and the 'r' command in the cpan shell :) – Calathus

Use of sudo is not recommended, as it affects the system packages and modules. AFAIK, at least in recent versions, cpan performs the setup automatically that creates a local installation for the regular user in the $HOME directory. – Plott

Answer 10

You can get list of perl modules installed in you system by using instmodsh command in your terminal.It will ask you three option in order to enhance the output they are:

   l            - List all installed modules
   m <module>   - Select a module
   q            - Quit the program

Colorado

Answer 11

On Linux/Unix I use this simple command:

perl -e 'print qx/find $_ -name "*.pm"/ foreach ( @INC );' 

It scans all folder in @INC and looks for any *.pm file.

Hertha

Answer 12

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe 'find { wanted => sub { print canonpath $_ if /\.pm\z/ }, no_chdir => 1 }, @INC'

Lippold

This is very good as it clearly show the full path to each *.pm module. You may see many duplicates... – Pomegranate

Answer 13

Here's a really hacky way to do it in *nix, you'll get some stuff you don't really care about (ie: warnings::register etc), but it should give you a list of every .pm file that's accessible via perl.

for my $path (@INC) {
    my @list = `ls -R $path/**/*.pm`;
    for (@list) {
        s/$path\///g;
        s/\//::/g;
        s/\.pm$//g;
        print;
    }
}

Yezd

This will not give him what he wants. It won't group related files by the distribution they are part of, and it will list all the core *.pm files from Perl itself. – Procedure

Answer 14

All those who can't install perldoc, or other modules, and want to know what modules are available (CPAN or otherwise), the following works for linux and Mingw32/64:

grep -RhIP '^package [A-Z][\w:]+;' `perl -e 'print join " ",@INC'` | sed 's/package //' | sort | uniq

Yes, it's messy. Yes, it probably reports more than you want. But if you pipe it into a file, you can easily check for, say, which dbm interfaces are present:

 grep -RhIP '^package [A-Z][\w:]+;' `perl -e 'print join " ",@INC'` | sed 's/package //' | sort | uniq > modules-installed
 cat modules-installed | grep -i dbm 

AnyDBM_File;
Memoize::AnyDBM_File;
Memoize::NDBM_File;
Memoize::SDBM_File;
WWW::RobotRules::AnyDBM_File;

Which is why I ended up on this page (disappointed)

(I realise this doesn't answer the OP's question exactly, but I'm posting it for anybody who ended up here for the same reason I did. That's the problem with stack*** it's almost imposisble to find the question you're asking, even when it exists, yet stack*** is nearly always google's top hit!)

Taitaichung

This worked for me. Thanks for posting this. I needed this in an environment where I don't have much access to install / update any dependencies. – Milano

This is the only method that worked for me (Cygwin on Windows 10) – Stickney

Answer 15

Here's a script by @JamesThomasMoon1979 rewritten as a one-liner

perl -MExtUtils::Installed -e '$i=ExtUtils::Installed->new(); 
      print "$_ ".$i->version($_)."\n" for $i->modules();'

Mcwherter

Answer 16

The answer can be found in the Perl FAQ list.

You should skim the excellent documentation that comes with Perl

perldoc perltoc

Chesterfield

Answer 17

Try man perllocal or perldoc perllocal.

Trussell

Answer 18

To walk through the @INC directory trees without using an external program like ls(1), one could use the File::Find::Rule module, which has a nice declarative interface.

Also, you want to filter out duplicates in case previous Perl versions contain the same modules. The code to do this looks like:

#! /usr/bin/perl -l

use strict;
use warnings;
use File::Find::Rule;

my %seen;
for my $path (@INC) {
    for my $file (File::Find::Rule->name('*.pm')->in($path)) {
        my $module = substr($file, length($path)+1);
        $module =~ s/.pm$//;
        $module =~ s{[\\/]}{::}g;
        print $module unless $seen{$module}++;
    }
}

At the end of the run, you also have all your module names as keys in the %seen hash. The code could be adapted to save the canonical filename (given in $file) as the value of the key instead of a count of times seen.

Rossen

Answer 19

I wrote a perl script just yesterday to do exactly this. The script returns the list of perl modules installed in @INC using the '::' as the separator. Call the script using -

perl perlmod.pl

OR

perl perlmod.pl <module name> #Case-insensitive(eg. perl perlmod.pl ftp)

As of now the script skips the current directory('.') since I was having problems with recursing soft-links but you can include it by changing the grep function in line 17 from

  grep { $_ !~ '^\.$' } @INC

to just,

@INC

The script can be found here.

Nummulite

Answer 20

Here is yet another command-line tool to list all installed .pm files:

Find installed Perl modules matching a regular expression

• Portable (only uses core modules)
• Cache option for faster look-up's
• Configurable display options

Cryptogam

Answer 21

The following worked for me.

$ perldoc perllocal | grep Module
$ perldoc perllocal | grep -E 'VERSION|Module'

Trustful

perldoc perllocal | grep "::" | cut -d" " -f9 | sort. I wonder why is not the same output as with instmodsh. – Wyoming

@PabloBianchi referring to Dan's answer behind, The entries of DBI, JSON, ... do not have any "::". It's my guess. It's easy for you to understand the difference in you system. – Trustful

Answer 22

the Perl cookbook contains several iterations of a script "pmdesc" that does what you want. Google-search for "Perl Cookbook pmdesc" and you'll find articles on other Q&A Sites, several code listings on the net, a discussion of the solution, and even some refinements.

Predetermine

Answer 23

Here's a Perl one-liner that will print out a list of installed modules:

perl -MExtUtils::Installed -MData::Dumper -e  'my ($inst) = ExtUtils::Installed->new(); print Dumper($inst->modules());'

Just make sure you have Data::Dumper installed.

Frantic

This only lists about 15 perl modules, instead of the 5945 that 'cpan -l' lists. – Thiel

Answer 24

cd /the/lib/dir/of/your/perl/installation
perldoc $(find . -name perllocal.pod)

Windows users just do a Windows Explorer search to find it.

Sclerotomy

Answer 25

Try "perldoc -l":

$ perldoc -l Log::Dispatch /usr/local/share/perl/5.26.1/Log/Dispatch.pm

Isom

Answer 26

As you enter your Perl script you have all the installed modules as .pm files below the folders in @INC so a small bash script will do the job for you:

#!/bin/bash

echo -e -n "Content-type: text/plain\n\n"

inc=`perl -e '$, = "\n"; print @INC;'`

for d in $inc
do
   find $d -name '*.pm'
done

Emunctory

Why not? find `perl -le'print for@INC'` -name '*.pm' – Bouilli

Answer 27

For Linux the easiest way to get is,

dpkg -l | grep "perl"

Fiver

the OP asked for a list of CPAN (perl) modules installed in the system, not if perl is installed in the system (neither the OP told us if apt is available) – Jackhammer

I'm not a perl expert but I have seen installed perl modules from above command. May be not the perfect answer here. – Fiver

@YasiruG it only lists those that have been installed via packages; that's a minority in any installation. Most of them are installed via CPAN. – Yseulta