I'm trying to ssh to multiple nodes in parallel via threads and it seems to work just fine. Only problem is when a node doesn't support passwordless ssh things go south.

My solution is to simply wait awhile in a loop, and if the ssh fails kill the thread. I read previous notes about setting up a signal handler in the thread and I tried that and it seems to work just fine. The reason I know this is I have a 'print' in the signal handler and I do see the results. Only problem was when the script eventually exits, it reports: 

Perl exited with active threads:
        0 running and unjoined
        1 finished and unjoined

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and I'm not sure what to do. What I did do was write a pretty small script that starts the thread, gives it a few seconds to run, and if the ssh doesn't finish and set a flag, it kills the thread. Only thing is now my signal isn't even firing! So now this is turning into a 2-part question:
- why doesn't the signal fire in the thread and
- if it does fire, how do I get rid of the 'unjoined' message at the end? 
#!/usr/bin/perl -w

use threads;
use threads::shared;
my $sshDone:shared;

$sshDone=0;
my $th=threads->create('test');
$th->join();

sleep 3;
if (!$sshDone)
{
  $th->kill('KILL');
  print "Kill signal sent\n";
}
sleep 2;

sub test
{
  $SIG{'KILL'} = sub { print "KILL THREAD\n"; threads->exit(); };

  `ssh foo\@poker date`;
  $sshDone=1;
}

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note - if I use a valid user/hostname the script runs just fine and exits cleanly.

what is happening now is I see the echo of the password prompt to the ssh and then nothing! If I remove the join, I see the 'kill signal sent' message but then it just hangs.

gotta be something simple but I'm just not seeing it.

-mark

In reply to yet another thread/signal question by markseger

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