Seems that this module is somwhat quirky, I could get it work only with some delay between sending a command and reading its output, and then the diamond operator doesn't seem to work on the $chan2 filehandle, but the read method does (linux, perl5.8.8):

#!/usr/bin/perl

use Net::SSH2;

my $ssh2 = Net::SSH2->new();

$ssh2->connect('somehost') or die;

if ($ssh2->auth_password('user','password')) {
    #shell use
    my $chan2 = $ssh2->channel();
    $chan2->shell();
    print $chan2 "uname -a\n";
    select(undef,undef,undef,0.2);
    my ($len, $buf);
    print $buf while ($len = $chan2->read($buf,512)) > 0;
    print $chan2 "who\n";
    select(undef,undef,undef,0.2);
    print $buf while ($len = $chan2->read($buf,512)) > 0;
    $chan2->close;
} else {
    warn "auth failed.\n";
}
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Those selects() could be replaced with calls to $chan2->poll(), which usage to find out is left as an excercise to the reader...

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