See Simple threaded chat server. Threads can share socket filehandles thru the fileno. Look at the multi-echo chat example. You can share the clients in a shared array.

So all you would need to do is create another thread for your keepalive signal, and put in it 

 foreach my $fn (@clients) { 
      open my $fh, ">&=$fn" or warn $! and die;
       print $fh  "keepalive\n"  
  }

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I'm not really a human, but I play one on earth. Cogito ergo sum a bum

In reply to Re: Printing to all clients on a socket from a child process by zentara
in thread Printing to all clients on a socket from a child process by Fredde87

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