Can we see the non-working code that uses alarm? This is a textbook example of when to use alarm.

Here, the alarm is triggered, and then processing continues: 

alarm 5;
$SIG{ALRM} = sub { print "alarm!\n" };
my $yawn = `sleep 10 ; echo "yawn"`;
print "yawn?  $yawn\n";
__END__
alarm!
yawn?  yawn

[download]

In this case (adapted from the example in the alarm documentation), the alarm is triggered, and processing is halted: 

my $yawn;
eval {
    local $SIG{ALRM} = sub { die "alarm\n" };
    alarm 5;
    $yawn = `sleep 10 ; echo "yawn"`;
    alarm 0;
};
print $@ ? 'Timed out.' : 'Finished.';
print "\n";
print "yawn? $yawn\n";
__END__
Timed out.
yawn?

[download]

In reply to Re: How to timeout if a call to an external program takes too long by kyle
in thread How to timeout if a call to an external program takes too long by deivakumar

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