With Deferred (or Safe) Signals enabled--the default since 5.8.something--there are (many) somethings that cannot be interrupted by SIGALRM.

Reading your later description of do_program(), it seems like that it is doing many, maybe even most, of those somethings.

You may find the use of Perl::Unsafe::Signals worth testing.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Perl Alarm Not Working by BrowserUk
in thread Perl Alarm Not Working by aceofspace

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