Hello,

I am trying to fork 4 children and pause until they have all completed their task and exited. Then I want to continue with the main script and fork off 4 more children wait until they are finished and then proceed with the script. However, I cannot get the main script to wait until all children have exited--so the script forks off 4 children and then 4 more and then continues running the rest of the script. The dead children become zombies and the whole thing crashes.

How do I reap my children as they exit AND wait until all 4 have exited before I continue with the script??

I have tried to continue only if the exit status ($?) is -1, and installed a signal handler, but it does not seem to be working...

any suggestions?

sub subroutine {

  $SIG{CHLD} = sub { wait }

  foreach (1..4) {

    unless ( $pid = fork ) {

           # do something here 

        }

    exit(0);

    }
  
  }

  until($? == '-1') { print "Waiting... Status is: $?\n" }

}

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In reply to fork n wait by Anonymous Monk

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