1. You have two processes trying to attempt the print: both the parent and the child. But you are setting $output in only one of them. And in the other, since "lst" fails, $output is set to undef.
  2. The parent will wait. The child, which doesn't have a child process $pid, will not.
  3. It won't show you anything because printing undef prints the empty string. Even with two empty strings, there's still nothing to see.

In reply to Re: Fork / use Warnings Confusion by JavaFan
in thread Fork / use Warnings Confusion by bichonfrise74

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