When a process forks execution continues in two processes at the same point. The difference is that in parent process the fork() returns the PID of the child and in the child it returns undef. So, in your example the parent enters the first branch of the if block and the child enters the second.

Perl didn't invent this behavior - fork() is just a think wrapper around the normal UNIX fork() system call. The behavior is the same.

-sam

In reply to Re: Question on how fork works. by samtregar
in thread Question on how fork works. by gnu@perl

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