Quote

$! If used numerically, yields the current value of the C "errno"
variable, or in other words, if a system or library call fails,
it sets this variable. This means that the value of $! is
meaningful only immediately after a failure:

1
2
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copy(...) or do {
    # schiefgegangen
};

Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live. -- Damian Conway in "Perl Best Practices"
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