Fork creates and runs a new instance of your program, just like if you ran it, except that the second program is a carbon copy of the first, at the point the fork occurs.

The program forks at the $pid=fork and suddenly there are two programs running, both doing the next statement (the if). The only difference is that one will have $pid = 0 and one will have $pid = 1234 or some number, being the pid of the child.

my $pid;
$pid = fork;
 if ( $pid ) {
  #We are the parent
  print "Successfully forked, I am the parent\n";
 } 
 else {
   if ( $pid == 0 ) {
   #We are the child
   print "Successfully forked, I am the child\n";
   
  }
  else {
   #undef value - no fork happened
   print "Fork failed for some strange reason\n";
   
  } 
 }
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I'm currently writing a module to do this and handle IPC as well. If you can hold on a few days I'll clean up the module and post it.

____________________
Jeremy
I didn't believe in evil until I dated it.