Keep in mind that perl fork does not return -1, it returns undef on failure. In your code, fork failure results in system() and exit() on the parent side. A useful idiom with fork is my $pid = fork() // die; you may want if (!defined $pid) {} else if ($pid) {} else {}.

Keep in mind that a call to system results in another fork and wait, hence your work runs in a child of a child. You may have intended a direct exec instead of system.

Your OP question is somewhat ambiguous. Just in case, I'll mention that there is no guarantee that a newly spawned child has a different pid from some earlier (already reaped) process. Pid numbers are recycled.

In reply to Re^3: Fork() Function by oiskuu
in thread Fork() Function by carlriz

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