It seems replacing the default signal is the cause of the alarm failing to go off. I do not understand why, even this simple replacement causes the alarm to not go off. 
   $SIG{ALRM} = sub { die "alarm" };

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Without it, the alarm does fire. Anyone can clarify why this is?

In reply to Re^2: Alarm and blocking I/O. by expresspotato
in thread Alarm and blocking I/O. by expresspotato

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