How to uninstall perl installed via cpan which conflicts with yum - perl

On my centos 6.3 server I installed perl via the yum install perl packager install
However, while installing ExtUtils/Embed via cpan cpan updated my Perl to v5.17.4 when it should be 5.10.1-127 (presumably some way via dependencies as I used the force install method).
So now i run into dozens of issues such as the error:
../x86_64-linux/CORE/libperl.a(op.o): relocation R_X86_64_32S against `PL_sv_yes' can not be used when making a shared object; recompile with -fPIC
Which I can't recompile with fpic because it was installed via cpan somehow. The compiler is using this new perl instead of the old compatible one which doesn't give me this error.
Is there a way I can uninstall this 5.17.4 perl? I've tried to use pm-uninstall.. etc to no avail. I've even tried yum reinstall perl yet the newer perl remains in use

This won't scrub everything, but should get you going again.
Record your installed perl rpms:
rpm -qa | grep ^perl > /tmp/perlpkgs
Force remove them:
for i in `cat /tmp/perlpkgs` ; do rpm -ev --nodeps $i ; done
Figure out where perl is installed in case cpan put it in /usr/local
which perl
If it prints /usr/local/bin/perl then P=/usr/local; otherwise P=/usr
Remove any perl binaries, etc,
rm -fr $P/bin/perl* $P/lib*/perl* $P/share/man/man?/perl*
rm -fr $P/share/man/man?/*.3pm* $P/share/perl*
Reinstall all of the original packages:
yum install `cat /tmp/perlpkgs`

Related

Cwd.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xde00080)

All Perl modules and 'cpan' stopped working after an upgrade of Ubuntu 16.04 LTS to 18.04 LTS. Every time I run my script it leads to the error
threads.c: loadable library and Perl binaries are mismatched (got handshake key 0xdb00080, needed 0xde00080)
when I try to open cpan it shows
Cwd.c: loadable library and Perl binaries are mismatched (got handshake key 0xdb00080, needed 0xde00080)
I had installed "Cwd", "threads" modules in ubuntu 16.04 where Perl version was 5.22.1, whereas in ubuntu 18.04 the Perl version is 5.26.1.
I tried to remove the old version of modules but failed. I deleted content on ~/.cpan folder.
PS:
Everything works fine in root user.
if I run
sudo su
cpan
works perfectly. But as a normal user, I cant run any perl modules/scripts/cpan.
How do I correct the issue?
How can I re-install cpan or cpan modules?
I tried to reinstall Perl which did not help
sudo apt-get --reinstall install perl
sudo apt-get --reinstall install libcwd-guard-perl
I installed cpan minus, cpan plus which gave the same error.
For solve problem next links can be used:
https://dev.to/foursixnine/about-perl-and-mismatched-binaries-346l
https://metacpan.org/pod/release/DBOOK/App-MigrateModules-0.002/script/perl-migrate-modules
Or in commands: (Replace to your perl5 folder, in my case it was ~/perl5)
mv <perl5> perl5_old
cpan
cpan App::MigrateModules
perl-migrate-modules --from perl5_old /usr/bin/perl
Where perl5 your perl folder, usually in path exists in ENV variable PERL5LIB.
I solved this issue by following https://github.com/Perl/perl5/issues/15861
I ran the command perl -MCPAN -e 'recompile()'
It recompile all the module, at last it worked.

Perl script debugging through the command line gives error [duplicate]

I get this error:
Can't locate Foo.pm in #INC
Is there an easier way to install it than downloading, untarring, making, etc?
On Unix:
usually you start cpan in your shell:
$ cpan
and type
install Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of the same functionality as CPAN.pm.
Example:
$ ppm
ppm> search net-smtp
ppm> install Net-SMTP-Multipart
see How do I install Perl modules? in the CPAN FAQ
Many distributions ship a lot of perl modules as packages.
Debian/Ubuntu: apt-cache search 'perl$'
Arch Linux: pacman -Ss '^perl-'
Gentoo: category dev-perl
You should always prefer them as you benefit from automatic (security) updates and the ease of removal. This can be pretty tricky with the cpan tool itself.
For Gentoo there's a nice tool called g-cpan which builds/installs the module from CPAN and creates a Gentoo package (ebuild) for you.
Try App::cpanminus:
# cpanm Chocolate::Belgian
It's great for just getting stuff installed. It provides none of the more complex functionality of CPAN or CPANPLUS, so it's easy to use, provided you know which module you want to install. If you haven't already got cpanminus, just type:
# cpan App::cpanminus
to install it.
It is also possible to install it without using cpan at all. The basic bootstrap procedure is,
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
For more information go to the App::cpanminus page and look at the section on installation.
I note some folks suggesting one run cpan under sudo. That used to be necessary to install into the system directory, but modern versions of the CPAN shell allow you to configure it to use sudo just for installing. This is much safer, since it means that tests don't run as root.
If you have an old CPAN shell, simply install the new cpan ("install CPAN") and when you reload the shell, it should prompt you to configure these new directives.
Nowadays, when I'm on a system with an old CPAN, the first thing I do is update the shell and set it up to do this so I can do most of my cpan work as a normal user.
Also, I'd strongly suggest that Windows users investigate strawberry Perl. This is a version of Perl that comes packaged with a pre-configured CPAN shell as well as a compiler. It also includes some hard-to-compile Perl modules with their external C library dependencies, notably XML::Parser. This means that you can do the same thing as every other Perl user when it comes to installing modules, and things tend to "just work" a lot more often.
If you're on Ubuntu and you want to install the pre-packaged perl module (for example, geo::ipfree) try this:
$ apt-cache search perl geo::ipfree
libgeo-ipfree-perl - A look up country of ip address Perl module
$ sudo apt-get install libgeo-ipfree-perl
A couple of people mentioned the cpan utility, but it's more than just starting a shell. Just give it the modules that you want to install and let it do it's work.
$prompt> cpan Foo::Bar
If you don't give it any arguments it starts the CPAN.pm shell. This works on Unix, Mac, and should be just fine on Windows (especially Strawberry Perl).
There are several other things that you can do with the cpan tool as well. Here's a summary of the current features (which might be newer than the one that comes with CPAN.pm and perl):
-a
Creates the CPAN.pm autobundle with CPAN::Shell->autobundle.
-A module [ module ... ]
Shows the primary maintainers for the specified modules
-C module [ module ... ]
Show the Changes files for the specified modules
-D module [ module ... ]
Show the module details. This prints one line for each out-of-date module (meaning,
modules locally installed but have newer versions on CPAN). Each line has three columns:
module name, local version, and CPAN version.
-L author [ author ... ]
List the modules by the specified authors.
-h
Prints a help message.
-O
Show the out-of-date modules.
-r
Recompiles dynamically loaded modules with CPAN::Shell->recompile.
-v
Print the script version and CPAN.pm version.
sudo perl -MCPAN -e 'install Foo'
Also see Yes, even you can use CPAN. It shows how you can use CPAN without having root or sudo access.
Otto made a good suggestion. This works for Debian too, as well as any other Debian derivative. The missing piece is what to do when apt-cache search doesn't find something.
$ sudo apt-get install dh-make-perl build-essential apt-file
$ sudo apt-file update
Then whenever you have a random module you wish to install:
$ cd ~/some/path
$ dh-make-perl --build --cpan Some::Random::Module
$ sudo dpkg -i libsome-random-module-perl-0.01-1_i386.deb
This will give you a deb package that you can install to get Some::Random::Module. One of the big benefits here is man pages and sample scripts in addition to the module itself will be placed in your distro's location of choice. If the distro ever comes out with an official package for a newer version of Some::Random::Module, it will automatically be installed when you apt-get upgrade.
Already answered and accepted answer - but anyway:
IMHO the easiest way installing CPAN modules (on unix like systems, and have no idea about the wondows) is:
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
The above is installing the "zero configuration CPAN modules installer" called cpanm. (Can take several minutes to install - don't break the process)
and after - simply:
cpanm Foo
cpanm Module::One
cpanm Another::Module
Many times it does happen that cpan install command fails with the message like
"make test had returned bad status, won't install without force"
In that case following is the way to install the module:
perl -MCPAN -e "CPAN::Shell->force(qw(install Foo::Bar));"
Lots of recommendation for CPAN.pm, which is great, but if you're using Perl 5.10 then you've also got access to CPANPLUS.pm which is like CPAN.pm but better.
And, of course, it's available on CPAN for people still using older versions of Perl. Why not try:
$ cpan CPANPLUS
Use cpan command as cpan Modulename
$ cpan HTML::Parser
To install dependencies automatically follow the below
$ perl -MCPAN -e shell
cpan[1]> o conf prerequisites_policy follow
cpan[2]> o conf commit
exit
I prefer App::cpanminus, it installs dependencies automatically. Just do
$ cpanm HTML::Parser
On ubuntu most perl modules are already packaged, so installing is much faster than most other systems which have to compile.
To install Foo::Bar at a commmand prompt for example usually you just do:
sudo apt-get install libfoo-bar-perl
Sadly not all modules follow that naming convention.
On Fedora Linux or Enterprise Linux, yum also tracks perl library dependencies. So, if the perl module is available, and some rpm package exports that dependency, it will install the right package for you.
yum install 'perl(Chocolate::Belgian)'
(most likely perl-Chocolate-Belgian package, or even ChocolateFactory package)
Even it should work:
cpan -i module_name
2 ways that I know of :
USING PPM :
With Windows (ActivePerl) I've used ppm
from the command line type ppm. At the ppm prompt ...
ppm> install foo
or
ppm> search foo
to get a list of foo modules available. Type help for all the commands
USING CPAN :
you can also use CPAN like this (*nix systems) :
perl -MCPAN -e 'shell'
gets you a prompt
cpan>
at the prompt ...
cpan> install foo (again to install the foo module)
type h to get a list of commands for cpan
On Fedora you can use
# yum install foo
as long as Fedora has an existing package for the module.
Easiest way for me is this:
PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install DateTime::TimeZone'
a) automatic recursive dependency detection/resolving/installing
b) it's a shell onliner, good for setup-scripts
If you want to put the new module into a custom location that your cpan shell isn't configured to use, then perhaps, the following will be handy.
#wget <URL to the module.tgz>
##unpack
perl Build.PL
./Build destdir=$HOME install_base=$HOME
./Build destdir=$HOME install_base=$HOME install
Sometimes you can use the yum search foo to search the relative perl module, then use yum install xxx to install.
Secure solution
Many answers mention the use of the cpan utility (which uses CPAN.pm) without a word on security. By default, CPAN 2.27 and earlier configures urllist to use a http URL (namely, http://www.cpan.org/), which allows MITM attacks, thus is insecure. This is what is used to download the CHECKSUMS files, so that it needs to be changed to a secure URL (e.g. https://www.cpan.org/).
So, after running cpan and accepting the default configuration, you need to modify the generated MyConfig.pm file (the full path is output) in the following way. Replace
'urllist' => [q[http://www.cpan.org/]],
by
'urllist' => [q[https://www.cpan.org/]],
Note: https is not sufficient; you also need a web site you can trust. So, be careful if you want to choose some arbitrary mirror.
Then you can use cpan in the usual way.
My bug report on rt.cpan.org about the insecure URL.
Simply executing cpan Foo::Bar on shell would serve the purpose.
Seems like you've already got your answer but I figured I'd chime in. This is what I do in some scripts on an Ubuntu (or debian server)
#!/usr/bin/perl
use warnings;
use strict;
#I've gotten into the habit of setting this on all my scripts, prevents weird path issues if the script is not being run by root
$ENV{'PATH'} = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin';
#Fill this with the perl modules required for your project
my #perl = qw(LWP::Simple XML::LibXML MIME::Lite DBI DateTime Config::Tiny Proc::ProcessTable);
chomp(my $curl = `which curl`);
if(!$curl){ system('apt-get install curl -y > /dev/null'); }
chomp(my $cpanm = system('/bin/bash', '-c', 'which cpanm &>/dev/null'));
#installs cpanm if missing
if($cpanm){ system('curl -s -L http://cpanmin.us | perl - --sudo App::cpanminus'); }
#loops through required modules and installs them if missing
foreach my $x (#perl){
eval "use $x";
if($#){
system("cpanm $x");
eval "use $x";
}
}
This works well for me, maybe there is something here you can use.
On Windows with the ActiveState distribution of Perl, use the ppm command.

Can't locate WWW/Curl/Easy.pm in #INC (#INC contains [duplicate]

I get this error:
Can't locate Foo.pm in #INC
Is there an easier way to install it than downloading, untarring, making, etc?
On Unix:
usually you start cpan in your shell:
$ cpan
and type
install Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of the same functionality as CPAN.pm.
Example:
$ ppm
ppm> search net-smtp
ppm> install Net-SMTP-Multipart
see How do I install Perl modules? in the CPAN FAQ
Many distributions ship a lot of perl modules as packages.
Debian/Ubuntu: apt-cache search 'perl$'
Arch Linux: pacman -Ss '^perl-'
Gentoo: category dev-perl
You should always prefer them as you benefit from automatic (security) updates and the ease of removal. This can be pretty tricky with the cpan tool itself.
For Gentoo there's a nice tool called g-cpan which builds/installs the module from CPAN and creates a Gentoo package (ebuild) for you.
Try App::cpanminus:
# cpanm Chocolate::Belgian
It's great for just getting stuff installed. It provides none of the more complex functionality of CPAN or CPANPLUS, so it's easy to use, provided you know which module you want to install. If you haven't already got cpanminus, just type:
# cpan App::cpanminus
to install it.
It is also possible to install it without using cpan at all. The basic bootstrap procedure is,
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
For more information go to the App::cpanminus page and look at the section on installation.
I note some folks suggesting one run cpan under sudo. That used to be necessary to install into the system directory, but modern versions of the CPAN shell allow you to configure it to use sudo just for installing. This is much safer, since it means that tests don't run as root.
If you have an old CPAN shell, simply install the new cpan ("install CPAN") and when you reload the shell, it should prompt you to configure these new directives.
Nowadays, when I'm on a system with an old CPAN, the first thing I do is update the shell and set it up to do this so I can do most of my cpan work as a normal user.
Also, I'd strongly suggest that Windows users investigate strawberry Perl. This is a version of Perl that comes packaged with a pre-configured CPAN shell as well as a compiler. It also includes some hard-to-compile Perl modules with their external C library dependencies, notably XML::Parser. This means that you can do the same thing as every other Perl user when it comes to installing modules, and things tend to "just work" a lot more often.
If you're on Ubuntu and you want to install the pre-packaged perl module (for example, geo::ipfree) try this:
$ apt-cache search perl geo::ipfree
libgeo-ipfree-perl - A look up country of ip address Perl module
$ sudo apt-get install libgeo-ipfree-perl
A couple of people mentioned the cpan utility, but it's more than just starting a shell. Just give it the modules that you want to install and let it do it's work.
$prompt> cpan Foo::Bar
If you don't give it any arguments it starts the CPAN.pm shell. This works on Unix, Mac, and should be just fine on Windows (especially Strawberry Perl).
There are several other things that you can do with the cpan tool as well. Here's a summary of the current features (which might be newer than the one that comes with CPAN.pm and perl):
-a
Creates the CPAN.pm autobundle with CPAN::Shell->autobundle.
-A module [ module ... ]
Shows the primary maintainers for the specified modules
-C module [ module ... ]
Show the Changes files for the specified modules
-D module [ module ... ]
Show the module details. This prints one line for each out-of-date module (meaning,
modules locally installed but have newer versions on CPAN). Each line has three columns:
module name, local version, and CPAN version.
-L author [ author ... ]
List the modules by the specified authors.
-h
Prints a help message.
-O
Show the out-of-date modules.
-r
Recompiles dynamically loaded modules with CPAN::Shell->recompile.
-v
Print the script version and CPAN.pm version.
sudo perl -MCPAN -e 'install Foo'
Also see Yes, even you can use CPAN. It shows how you can use CPAN without having root or sudo access.
Otto made a good suggestion. This works for Debian too, as well as any other Debian derivative. The missing piece is what to do when apt-cache search doesn't find something.
$ sudo apt-get install dh-make-perl build-essential apt-file
$ sudo apt-file update
Then whenever you have a random module you wish to install:
$ cd ~/some/path
$ dh-make-perl --build --cpan Some::Random::Module
$ sudo dpkg -i libsome-random-module-perl-0.01-1_i386.deb
This will give you a deb package that you can install to get Some::Random::Module. One of the big benefits here is man pages and sample scripts in addition to the module itself will be placed in your distro's location of choice. If the distro ever comes out with an official package for a newer version of Some::Random::Module, it will automatically be installed when you apt-get upgrade.
Already answered and accepted answer - but anyway:
IMHO the easiest way installing CPAN modules (on unix like systems, and have no idea about the wondows) is:
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
The above is installing the "zero configuration CPAN modules installer" called cpanm. (Can take several minutes to install - don't break the process)
and after - simply:
cpanm Foo
cpanm Module::One
cpanm Another::Module
Many times it does happen that cpan install command fails with the message like
"make test had returned bad status, won't install without force"
In that case following is the way to install the module:
perl -MCPAN -e "CPAN::Shell->force(qw(install Foo::Bar));"
Lots of recommendation for CPAN.pm, which is great, but if you're using Perl 5.10 then you've also got access to CPANPLUS.pm which is like CPAN.pm but better.
And, of course, it's available on CPAN for people still using older versions of Perl. Why not try:
$ cpan CPANPLUS
Use cpan command as cpan Modulename
$ cpan HTML::Parser
To install dependencies automatically follow the below
$ perl -MCPAN -e shell
cpan[1]> o conf prerequisites_policy follow
cpan[2]> o conf commit
exit
I prefer App::cpanminus, it installs dependencies automatically. Just do
$ cpanm HTML::Parser
On ubuntu most perl modules are already packaged, so installing is much faster than most other systems which have to compile.
To install Foo::Bar at a commmand prompt for example usually you just do:
sudo apt-get install libfoo-bar-perl
Sadly not all modules follow that naming convention.
On Fedora Linux or Enterprise Linux, yum also tracks perl library dependencies. So, if the perl module is available, and some rpm package exports that dependency, it will install the right package for you.
yum install 'perl(Chocolate::Belgian)'
(most likely perl-Chocolate-Belgian package, or even ChocolateFactory package)
Even it should work:
cpan -i module_name
2 ways that I know of :
USING PPM :
With Windows (ActivePerl) I've used ppm
from the command line type ppm. At the ppm prompt ...
ppm> install foo
or
ppm> search foo
to get a list of foo modules available. Type help for all the commands
USING CPAN :
you can also use CPAN like this (*nix systems) :
perl -MCPAN -e 'shell'
gets you a prompt
cpan>
at the prompt ...
cpan> install foo (again to install the foo module)
type h to get a list of commands for cpan
On Fedora you can use
# yum install foo
as long as Fedora has an existing package for the module.
Easiest way for me is this:
PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install DateTime::TimeZone'
a) automatic recursive dependency detection/resolving/installing
b) it's a shell onliner, good for setup-scripts
If you want to put the new module into a custom location that your cpan shell isn't configured to use, then perhaps, the following will be handy.
#wget <URL to the module.tgz>
##unpack
perl Build.PL
./Build destdir=$HOME install_base=$HOME
./Build destdir=$HOME install_base=$HOME install
Sometimes you can use the yum search foo to search the relative perl module, then use yum install xxx to install.
Secure solution
Many answers mention the use of the cpan utility (which uses CPAN.pm) without a word on security. By default, CPAN 2.27 and earlier configures urllist to use a http URL (namely, http://www.cpan.org/), which allows MITM attacks, thus is insecure. This is what is used to download the CHECKSUMS files, so that it needs to be changed to a secure URL (e.g. https://www.cpan.org/).
So, after running cpan and accepting the default configuration, you need to modify the generated MyConfig.pm file (the full path is output) in the following way. Replace
'urllist' => [q[http://www.cpan.org/]],
by
'urllist' => [q[https://www.cpan.org/]],
Note: https is not sufficient; you also need a web site you can trust. So, be careful if you want to choose some arbitrary mirror.
Then you can use cpan in the usual way.
My bug report on rt.cpan.org about the insecure URL.
Simply executing cpan Foo::Bar on shell would serve the purpose.
Seems like you've already got your answer but I figured I'd chime in. This is what I do in some scripts on an Ubuntu (or debian server)
#!/usr/bin/perl
use warnings;
use strict;
#I've gotten into the habit of setting this on all my scripts, prevents weird path issues if the script is not being run by root
$ENV{'PATH'} = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin';
#Fill this with the perl modules required for your project
my #perl = qw(LWP::Simple XML::LibXML MIME::Lite DBI DateTime Config::Tiny Proc::ProcessTable);
chomp(my $curl = `which curl`);
if(!$curl){ system('apt-get install curl -y > /dev/null'); }
chomp(my $cpanm = system('/bin/bash', '-c', 'which cpanm &>/dev/null'));
#installs cpanm if missing
if($cpanm){ system('curl -s -L http://cpanmin.us | perl - --sudo App::cpanminus'); }
#loops through required modules and installs them if missing
foreach my $x (#perl){
eval "use $x";
if($#){
system("cpanm $x");
eval "use $x";
}
}
This works well for me, maybe there is something here you can use.
On Windows with the ActiveState distribution of Perl, use the ppm command.

Can't locate File/ShareDir/Install.pm in #INC [duplicate]

I get this error:
Can't locate Foo.pm in #INC
Is there an easier way to install it than downloading, untarring, making, etc?
On Unix:
usually you start cpan in your shell:
$ cpan
and type
install Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of the same functionality as CPAN.pm.
Example:
$ ppm
ppm> search net-smtp
ppm> install Net-SMTP-Multipart
see How do I install Perl modules? in the CPAN FAQ
Many distributions ship a lot of perl modules as packages.
Debian/Ubuntu: apt-cache search 'perl$'
Arch Linux: pacman -Ss '^perl-'
Gentoo: category dev-perl
You should always prefer them as you benefit from automatic (security) updates and the ease of removal. This can be pretty tricky with the cpan tool itself.
For Gentoo there's a nice tool called g-cpan which builds/installs the module from CPAN and creates a Gentoo package (ebuild) for you.
Try App::cpanminus:
# cpanm Chocolate::Belgian
It's great for just getting stuff installed. It provides none of the more complex functionality of CPAN or CPANPLUS, so it's easy to use, provided you know which module you want to install. If you haven't already got cpanminus, just type:
# cpan App::cpanminus
to install it.
It is also possible to install it without using cpan at all. The basic bootstrap procedure is,
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
For more information go to the App::cpanminus page and look at the section on installation.
I note some folks suggesting one run cpan under sudo. That used to be necessary to install into the system directory, but modern versions of the CPAN shell allow you to configure it to use sudo just for installing. This is much safer, since it means that tests don't run as root.
If you have an old CPAN shell, simply install the new cpan ("install CPAN") and when you reload the shell, it should prompt you to configure these new directives.
Nowadays, when I'm on a system with an old CPAN, the first thing I do is update the shell and set it up to do this so I can do most of my cpan work as a normal user.
Also, I'd strongly suggest that Windows users investigate strawberry Perl. This is a version of Perl that comes packaged with a pre-configured CPAN shell as well as a compiler. It also includes some hard-to-compile Perl modules with their external C library dependencies, notably XML::Parser. This means that you can do the same thing as every other Perl user when it comes to installing modules, and things tend to "just work" a lot more often.
If you're on Ubuntu and you want to install the pre-packaged perl module (for example, geo::ipfree) try this:
$ apt-cache search perl geo::ipfree
libgeo-ipfree-perl - A look up country of ip address Perl module
$ sudo apt-get install libgeo-ipfree-perl
A couple of people mentioned the cpan utility, but it's more than just starting a shell. Just give it the modules that you want to install and let it do it's work.
$prompt> cpan Foo::Bar
If you don't give it any arguments it starts the CPAN.pm shell. This works on Unix, Mac, and should be just fine on Windows (especially Strawberry Perl).
There are several other things that you can do with the cpan tool as well. Here's a summary of the current features (which might be newer than the one that comes with CPAN.pm and perl):
-a
Creates the CPAN.pm autobundle with CPAN::Shell->autobundle.
-A module [ module ... ]
Shows the primary maintainers for the specified modules
-C module [ module ... ]
Show the Changes files for the specified modules
-D module [ module ... ]
Show the module details. This prints one line for each out-of-date module (meaning,
modules locally installed but have newer versions on CPAN). Each line has three columns:
module name, local version, and CPAN version.
-L author [ author ... ]
List the modules by the specified authors.
-h
Prints a help message.
-O
Show the out-of-date modules.
-r
Recompiles dynamically loaded modules with CPAN::Shell->recompile.
-v
Print the script version and CPAN.pm version.
sudo perl -MCPAN -e 'install Foo'
Also see Yes, even you can use CPAN. It shows how you can use CPAN without having root or sudo access.
Otto made a good suggestion. This works for Debian too, as well as any other Debian derivative. The missing piece is what to do when apt-cache search doesn't find something.
$ sudo apt-get install dh-make-perl build-essential apt-file
$ sudo apt-file update
Then whenever you have a random module you wish to install:
$ cd ~/some/path
$ dh-make-perl --build --cpan Some::Random::Module
$ sudo dpkg -i libsome-random-module-perl-0.01-1_i386.deb
This will give you a deb package that you can install to get Some::Random::Module. One of the big benefits here is man pages and sample scripts in addition to the module itself will be placed in your distro's location of choice. If the distro ever comes out with an official package for a newer version of Some::Random::Module, it will automatically be installed when you apt-get upgrade.
Already answered and accepted answer - but anyway:
IMHO the easiest way installing CPAN modules (on unix like systems, and have no idea about the wondows) is:
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
The above is installing the "zero configuration CPAN modules installer" called cpanm. (Can take several minutes to install - don't break the process)
and after - simply:
cpanm Foo
cpanm Module::One
cpanm Another::Module
Many times it does happen that cpan install command fails with the message like
"make test had returned bad status, won't install without force"
In that case following is the way to install the module:
perl -MCPAN -e "CPAN::Shell->force(qw(install Foo::Bar));"
Lots of recommendation for CPAN.pm, which is great, but if you're using Perl 5.10 then you've also got access to CPANPLUS.pm which is like CPAN.pm but better.
And, of course, it's available on CPAN for people still using older versions of Perl. Why not try:
$ cpan CPANPLUS
Use cpan command as cpan Modulename
$ cpan HTML::Parser
To install dependencies automatically follow the below
$ perl -MCPAN -e shell
cpan[1]> o conf prerequisites_policy follow
cpan[2]> o conf commit
exit
I prefer App::cpanminus, it installs dependencies automatically. Just do
$ cpanm HTML::Parser
On ubuntu most perl modules are already packaged, so installing is much faster than most other systems which have to compile.
To install Foo::Bar at a commmand prompt for example usually you just do:
sudo apt-get install libfoo-bar-perl
Sadly not all modules follow that naming convention.
On Fedora Linux or Enterprise Linux, yum also tracks perl library dependencies. So, if the perl module is available, and some rpm package exports that dependency, it will install the right package for you.
yum install 'perl(Chocolate::Belgian)'
(most likely perl-Chocolate-Belgian package, or even ChocolateFactory package)
Even it should work:
cpan -i module_name
2 ways that I know of :
USING PPM :
With Windows (ActivePerl) I've used ppm
from the command line type ppm. At the ppm prompt ...
ppm> install foo
or
ppm> search foo
to get a list of foo modules available. Type help for all the commands
USING CPAN :
you can also use CPAN like this (*nix systems) :
perl -MCPAN -e 'shell'
gets you a prompt
cpan>
at the prompt ...
cpan> install foo (again to install the foo module)
type h to get a list of commands for cpan
On Fedora you can use
# yum install foo
as long as Fedora has an existing package for the module.
Easiest way for me is this:
PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install DateTime::TimeZone'
a) automatic recursive dependency detection/resolving/installing
b) it's a shell onliner, good for setup-scripts
If you want to put the new module into a custom location that your cpan shell isn't configured to use, then perhaps, the following will be handy.
#wget <URL to the module.tgz>
##unpack
perl Build.PL
./Build destdir=$HOME install_base=$HOME
./Build destdir=$HOME install_base=$HOME install
Sometimes you can use the yum search foo to search the relative perl module, then use yum install xxx to install.
Secure solution
Many answers mention the use of the cpan utility (which uses CPAN.pm) without a word on security. By default, CPAN 2.27 and earlier configures urllist to use a http URL (namely, http://www.cpan.org/), which allows MITM attacks, thus is insecure. This is what is used to download the CHECKSUMS files, so that it needs to be changed to a secure URL (e.g. https://www.cpan.org/).
So, after running cpan and accepting the default configuration, you need to modify the generated MyConfig.pm file (the full path is output) in the following way. Replace
'urllist' => [q[http://www.cpan.org/]],
by
'urllist' => [q[https://www.cpan.org/]],
Note: https is not sufficient; you also need a web site you can trust. So, be careful if you want to choose some arbitrary mirror.
Then you can use cpan in the usual way.
My bug report on rt.cpan.org about the insecure URL.
Simply executing cpan Foo::Bar on shell would serve the purpose.
Seems like you've already got your answer but I figured I'd chime in. This is what I do in some scripts on an Ubuntu (or debian server)
#!/usr/bin/perl
use warnings;
use strict;
#I've gotten into the habit of setting this on all my scripts, prevents weird path issues if the script is not being run by root
$ENV{'PATH'} = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin';
#Fill this with the perl modules required for your project
my #perl = qw(LWP::Simple XML::LibXML MIME::Lite DBI DateTime Config::Tiny Proc::ProcessTable);
chomp(my $curl = `which curl`);
if(!$curl){ system('apt-get install curl -y > /dev/null'); }
chomp(my $cpanm = system('/bin/bash', '-c', 'which cpanm &>/dev/null'));
#installs cpanm if missing
if($cpanm){ system('curl -s -L http://cpanmin.us | perl - --sudo App::cpanminus'); }
#loops through required modules and installs them if missing
foreach my $x (#perl){
eval "use $x";
if($#){
system("cpanm $x");
eval "use $x";
}
}
This works well for me, maybe there is something here you can use.
On Windows with the ActiveState distribution of Perl, use the ppm command.

What's the easiest way to install a missing Perl module?

I get this error:
Can't locate Foo.pm in #INC
Is there an easier way to install it than downloading, untarring, making, etc?
On Unix:
usually you start cpan in your shell:
$ cpan
and type
install Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of the same functionality as CPAN.pm.
Example:
$ ppm
ppm> search net-smtp
ppm> install Net-SMTP-Multipart
see How do I install Perl modules? in the CPAN FAQ
Many distributions ship a lot of perl modules as packages.
Debian/Ubuntu: apt-cache search 'perl$'
Arch Linux: pacman -Ss '^perl-'
Gentoo: category dev-perl
You should always prefer them as you benefit from automatic (security) updates and the ease of removal. This can be pretty tricky with the cpan tool itself.
For Gentoo there's a nice tool called g-cpan which builds/installs the module from CPAN and creates a Gentoo package (ebuild) for you.
Try App::cpanminus:
# cpanm Chocolate::Belgian
It's great for just getting stuff installed. It provides none of the more complex functionality of CPAN or CPANPLUS, so it's easy to use, provided you know which module you want to install. If you haven't already got cpanminus, just type:
# cpan App::cpanminus
to install it.
It is also possible to install it without using cpan at all. The basic bootstrap procedure is,
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
For more information go to the App::cpanminus page and look at the section on installation.
I note some folks suggesting one run cpan under sudo. That used to be necessary to install into the system directory, but modern versions of the CPAN shell allow you to configure it to use sudo just for installing. This is much safer, since it means that tests don't run as root.
If you have an old CPAN shell, simply install the new cpan ("install CPAN") and when you reload the shell, it should prompt you to configure these new directives.
Nowadays, when I'm on a system with an old CPAN, the first thing I do is update the shell and set it up to do this so I can do most of my cpan work as a normal user.
Also, I'd strongly suggest that Windows users investigate strawberry Perl. This is a version of Perl that comes packaged with a pre-configured CPAN shell as well as a compiler. It also includes some hard-to-compile Perl modules with their external C library dependencies, notably XML::Parser. This means that you can do the same thing as every other Perl user when it comes to installing modules, and things tend to "just work" a lot more often.
If you're on Ubuntu and you want to install the pre-packaged perl module (for example, geo::ipfree) try this:
$ apt-cache search perl geo::ipfree
libgeo-ipfree-perl - A look up country of ip address Perl module
$ sudo apt-get install libgeo-ipfree-perl
A couple of people mentioned the cpan utility, but it's more than just starting a shell. Just give it the modules that you want to install and let it do it's work.
$prompt> cpan Foo::Bar
If you don't give it any arguments it starts the CPAN.pm shell. This works on Unix, Mac, and should be just fine on Windows (especially Strawberry Perl).
There are several other things that you can do with the cpan tool as well. Here's a summary of the current features (which might be newer than the one that comes with CPAN.pm and perl):
-a
Creates the CPAN.pm autobundle with CPAN::Shell->autobundle.
-A module [ module ... ]
Shows the primary maintainers for the specified modules
-C module [ module ... ]
Show the Changes files for the specified modules
-D module [ module ... ]
Show the module details. This prints one line for each out-of-date module (meaning,
modules locally installed but have newer versions on CPAN). Each line has three columns:
module name, local version, and CPAN version.
-L author [ author ... ]
List the modules by the specified authors.
-h
Prints a help message.
-O
Show the out-of-date modules.
-r
Recompiles dynamically loaded modules with CPAN::Shell->recompile.
-v
Print the script version and CPAN.pm version.
sudo perl -MCPAN -e 'install Foo'
Also see Yes, even you can use CPAN. It shows how you can use CPAN without having root or sudo access.
Otto made a good suggestion. This works for Debian too, as well as any other Debian derivative. The missing piece is what to do when apt-cache search doesn't find something.
$ sudo apt-get install dh-make-perl build-essential apt-file
$ sudo apt-file update
Then whenever you have a random module you wish to install:
$ cd ~/some/path
$ dh-make-perl --build --cpan Some::Random::Module
$ sudo dpkg -i libsome-random-module-perl-0.01-1_i386.deb
This will give you a deb package that you can install to get Some::Random::Module. One of the big benefits here is man pages and sample scripts in addition to the module itself will be placed in your distro's location of choice. If the distro ever comes out with an official package for a newer version of Some::Random::Module, it will automatically be installed when you apt-get upgrade.
Already answered and accepted answer - but anyway:
IMHO the easiest way installing CPAN modules (on unix like systems, and have no idea about the wondows) is:
curl -L http://cpanmin.us | perl - --sudo App::cpanminus
The above is installing the "zero configuration CPAN modules installer" called cpanm. (Can take several minutes to install - don't break the process)
and after - simply:
cpanm Foo
cpanm Module::One
cpanm Another::Module
Many times it does happen that cpan install command fails with the message like
"make test had returned bad status, won't install without force"
In that case following is the way to install the module:
perl -MCPAN -e "CPAN::Shell->force(qw(install Foo::Bar));"
Lots of recommendation for CPAN.pm, which is great, but if you're using Perl 5.10 then you've also got access to CPANPLUS.pm which is like CPAN.pm but better.
And, of course, it's available on CPAN for people still using older versions of Perl. Why not try:
$ cpan CPANPLUS
Use cpan command as cpan Modulename
$ cpan HTML::Parser
To install dependencies automatically follow the below
$ perl -MCPAN -e shell
cpan[1]> o conf prerequisites_policy follow
cpan[2]> o conf commit
exit
I prefer App::cpanminus, it installs dependencies automatically. Just do
$ cpanm HTML::Parser
On ubuntu most perl modules are already packaged, so installing is much faster than most other systems which have to compile.
To install Foo::Bar at a commmand prompt for example usually you just do:
sudo apt-get install libfoo-bar-perl
Sadly not all modules follow that naming convention.
On Fedora Linux or Enterprise Linux, yum also tracks perl library dependencies. So, if the perl module is available, and some rpm package exports that dependency, it will install the right package for you.
yum install 'perl(Chocolate::Belgian)'
(most likely perl-Chocolate-Belgian package, or even ChocolateFactory package)
Even it should work:
cpan -i module_name
2 ways that I know of :
USING PPM :
With Windows (ActivePerl) I've used ppm
from the command line type ppm. At the ppm prompt ...
ppm> install foo
or
ppm> search foo
to get a list of foo modules available. Type help for all the commands
USING CPAN :
you can also use CPAN like this (*nix systems) :
perl -MCPAN -e 'shell'
gets you a prompt
cpan>
at the prompt ...
cpan> install foo (again to install the foo module)
type h to get a list of commands for cpan
On Fedora you can use
# yum install foo
as long as Fedora has an existing package for the module.
Easiest way for me is this:
PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install DateTime::TimeZone'
a) automatic recursive dependency detection/resolving/installing
b) it's a shell onliner, good for setup-scripts
If you want to put the new module into a custom location that your cpan shell isn't configured to use, then perhaps, the following will be handy.
#wget <URL to the module.tgz>
##unpack
perl Build.PL
./Build destdir=$HOME install_base=$HOME
./Build destdir=$HOME install_base=$HOME install
Sometimes you can use the yum search foo to search the relative perl module, then use yum install xxx to install.
Secure solution
Many answers mention the use of the cpan utility (which uses CPAN.pm) without a word on security. By default, CPAN 2.27 and earlier configures urllist to use a http URL (namely, http://www.cpan.org/), which allows MITM attacks, thus is insecure. This is what is used to download the CHECKSUMS files, so that it needs to be changed to a secure URL (e.g. https://www.cpan.org/).
So, after running cpan and accepting the default configuration, you need to modify the generated MyConfig.pm file (the full path is output) in the following way. Replace
'urllist' => [q[http://www.cpan.org/]],
by
'urllist' => [q[https://www.cpan.org/]],
Note: https is not sufficient; you also need a web site you can trust. So, be careful if you want to choose some arbitrary mirror.
Then you can use cpan in the usual way.
My bug report on rt.cpan.org about the insecure URL.
Simply executing cpan Foo::Bar on shell would serve the purpose.
Seems like you've already got your answer but I figured I'd chime in. This is what I do in some scripts on an Ubuntu (or debian server)
#!/usr/bin/perl
use warnings;
use strict;
#I've gotten into the habit of setting this on all my scripts, prevents weird path issues if the script is not being run by root
$ENV{'PATH'} = '/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin';
#Fill this with the perl modules required for your project
my #perl = qw(LWP::Simple XML::LibXML MIME::Lite DBI DateTime Config::Tiny Proc::ProcessTable);
chomp(my $curl = `which curl`);
if(!$curl){ system('apt-get install curl -y > /dev/null'); }
chomp(my $cpanm = system('/bin/bash', '-c', 'which cpanm &>/dev/null'));
#installs cpanm if missing
if($cpanm){ system('curl -s -L http://cpanmin.us | perl - --sudo App::cpanminus'); }
#loops through required modules and installs them if missing
foreach my $x (#perl){
eval "use $x";
if($#){
system("cpanm $x");
eval "use $x";
}
}
This works well for me, maybe there is something here you can use.
On Windows with the ActiveState distribution of Perl, use the ppm command.