Perlbrew cannot run simple scripts IPC::System::Simple required for Fatalised/autodying system()

Question

I am a new perlbrew user, as I wish to upgrade to perl 5.30.0 on Ubuntu.

I have done

perlbrew init
perlbrew install perl-5.30.0
perlbrew switch perl-5.30.0

so I try to run this test script:

#!/usr/bin/env perl

use strict;
use warnings FATAL => 'all';
use feature 'say';
use autodie ':all';

but this gives the long error

IPC::System::Simple required for Fatalised/autodying system() at /home/con/Scripts/say.pl line 6.
    main::BEGIN() called at /home/con/Scripts/say.pl line 6
    eval {...} called at /home/con/Scripts/say.pl line 6
BEGIN failed--compilation aborted at /home/con/Scripts/say.pl line 6.
Command exited with non-zero status 2

I thought that libraries (especially standard ones) were supposed to be loaded automatically via perlbrew? How can I get this simple script to run?

Answer 1

From autodie we see that it's documented behavior

If system is specified as an argument to autodie , then it uses IPC::System::Simple to do the heavy lifting. See the description of that module for more information.

So one does need IPC::System::Simple installed for :all tag (which implies system ).

It strikes me as curious that a core functionality requires a non-core module, and quietly too (doesn't complain at installation).

Answer 2

I'm getting exactly the same error on a non-perlbrew Perl. It seems autodie requires IPC::System::Simple when running under fatal warnings or with :all , but it doesn't require it during installation.

See also https://bugzilla.redhat.com/show_bug.cgi?id=1183231 .

Answer 3

The solution, according to @ikegami, and that worked for me: /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/perl -e'use IPC::System::Simple'; /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/cpan IPC::System::Simple; /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/perl -e'use IPC::System::Simple' /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/perl -e'use IPC::System::Simple'; /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/cpan IPC::System::Simple; /home/con/perl5/perlbrew/perls/perl-5.30.0/bin/perl -e'use IPC::System::Simple'

of course, for anyone in the future, this will be slightly different for you, as your directories may be set differently, and username isn't con