Hi Gurus:
Im writing some perl that will execute an interactive command at some point in the code. The command is proprietary, but functions something like the sqlplus command, ie it pauses while connecting to a db, and gives a prompt. Between executing commands, there is typically a pause in which no input can be issued. Normally, I would use Expect to do this, but the system is in production, and the customer will not let me install new perl modules on it.

I was going to do this.... 

$|=1;
$N_CONS = "/usr/bin/ncons";
open (CONS, "| $N_CONS");
sleep 5;
print CONS "config execute test.cfg \n";
sleep 5;
print CONS "config save \n";
sleep 5;
print CONS "quit \n";
sleep 5;
close (CONS);

[download]
As I suspected, even with  sleep () between the  print statements, the commands get run too quickly to be processed by the called command. In fact, it generally closes the filehandle before it even gets to run the "quit" piece, leaving the script hanging until I send it a SIGTERM. Setting  $|=1 doesnt help either. Any suggestions?

-chris

In reply to Interactive Input without Expect.pm by sagat

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