I have a newbie question. I have used fork before, but I am not completely clear on how it works. Here is a little sample script I wrote to help illustrate my question: 
#!/usr/bin/perl -w

if ($pid = fork)
{ print "1. in pid $$\n";
  waitpid($pid,0);
} else {
  print "2. in pid $$\n";
}

[download]
From what I understand, when you 'fork' a new copy of your complete program is started. My main question is this, where does the execution start from in the fork-ed program? It obviously cannot start from the beginning or it would go on forking forever. In my little example I understand why 'print "1. in pid $$\n";' is executed in the parent process ( ($pid = fork) is true), but why is it not executed in the child as well? If execution started from the beginning, it would fork again. Also, why in the child process does ($pid = fork) evaluate to false and run the 'else' portion? I hope I explained things clearly and TIA for your help. Chad.

In reply to Question on how fork works. by gnu@perl

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