Several issues.

  1. you are doing 2 forks.
  2. you confounded parent and child code. The child writes to, the parent reads from the pipe. 
    if ($pid = fork) { # parent
   ...
}
elsif ($pid == 0) { child
   ...
   exit;
}

    [download]
  3. don't forget to exit the child in the elsif branch to stop it executing any following code of the parent.
  4. you need a signal handler in the parent for it to get notified about the child having exited.
    Otherwise the parent will try to get a line from its pipe handle when there isn't any.

Last, you need loops in the parent and the child functions for the repeating to happen.

<Reveal this spoiler or all in this thread>

Try to fix your program first, then read the spoiler ;-)

perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: Creating a Pipe by shmem
in thread Creating a Pipe by grjoe21

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