Why do you need to read your data synchronously? Why not read lines from your command asynchronously, and create the messages in a callback? There are many AnyEvent modules to make running and getting output back from external commands easy, but there is also AnyEvent::Util::fork_call (which serialises the whole output of your command before calling the callback).

Alternatively, you could probably use an IO watcher like this:
open my $fh, '-|', 'some command';
my $w; $w = AnyEvent->io(
        fh   => $fh,
        poll => 'r',
        cb   => sub {
                chomp(my $user = $fh->getline);
                AnyEvent::XMPP::IM::Message->new(
                        body => construct_body( $msg->body, $from ),
                        to   => "$user\@" . HOST,
                        type => "chat",
                )->send($conn);
                undef $w if eof($fh);
        } );

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In reply to Re: AnyEvent weirdness w/ open() and/or ``'s by james2vegas
in thread AnyEvent weirdness w/ open() and/or ``'s by pprocacci

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