Because after the fork there's two different processes with two different copies of $a. The child modifies its $a, but the parent's copy is unmodified. You'd either need to use threads (which have their own headaches) or something like IPC::Shareable to make a single variable visible in multiple execution contexts.

In reply to Re: Keeping variables throug a fork by Fletch
in thread Keeping variables throug a fork by Anonymous Monk

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