I need to send some commands to remote linux box and fetch responses. I am using Net:SSH2 for creating a session channel and send commands using shell.

The problem I face is that the response I receive is empty. If I add a sleep statement, the output is very well captured. I do not want to add sleep statements as I need to send multiple commands and that would reduce the performance. Please advice what I am missing.

Here is the code.

 
$session = Net::SSH2->new();
$rc = $session->connect($target_ip, $target_port, Timeout=>4000) ;

print "\n rc: $rc";
$session->auth_password($username, $passwd) ;

$chan = $session->channel();

$chan->shell() ;
print $chan $cmd . " \n" ;

my @poll = ({handle=>$chan, events=>['in', 'ext', 'channel_closed']});

$session->blocking(0) ;
$session->poll(1, \@poll) ;
        
        if ($poll[0]->{revents}->{in}) {
            while (<$chan>) {
             $resp  .= $_ ;
            }
        }
        
print "\nresponse : $resp";

[download]

Updates: We found out the issue here.

The problem is, once we receive the cmd output, the EOF is not reaching and so the channel is not getting closed automatically.

Question: How will SSH channel know that the cmd it sent has returned the complete output and when should it close its channel?

In reply to Net::SSH2 channel returns no output by rama133101

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