How can it get undef back, without $! being set?

readline (for which <$fh> is a shortcut) returns undef on end of file as well as on error.

By the way, there's no way to know if $! is meaningful after readline because readline has no way of signaling an error occurred.

In reply to Re: "Impossible" socket error return by ikegami
in thread "Impossible" socket error return by dd-b

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