use strict; 
use Net::SSH2; 

my $ssh2 = Net::SSH2->new(); 
$ssh2->connect('host')
 or die "Unable to connect host $@ \n"; 
$ssh2->auth_password('user','pass'); 
my $buflen = 512;
my $buf2 = '0' x $buflen;
my $chan = $ssh2->channel();
$chan->blocking(0);
$chan->shell();
$chan->write("ls\n");
select(undef,undef,undef,0.25);
my $len = $chan->read($buf2,$buflen);
print $buf2, "\n";