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in reply to Signals in Strawberry Perl: Name or number?

This was my test code:
#!/usr/bin/perl

use strict;
use warnings;

$SIG{ALRM} = sub {
   print "Alarming!\n";
};

kill 'ALRM', $$;

print "Not alarming\n";

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(The quotes around 'ALRM' required for strict).
I don't have Strawberry Perl, but I tried it on ActiveState Perl 5.10.1 and got the same result, i.e. no output. I tried it on 5.10.0 on Cygwin and 5.8.8 on CentOS(Linux) and it worked correctly, i.e.
Alarming!
Not alarming

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On Windows and ActiveState perl, tracing shows that it does exit on the kill. I tried the same with an INT signal and that did not work either, however the symptoms were different. It did not execute the signal handler but it did not crash either.

The ActiveState documentation says that alarm is not supported and signals are not properly supported anyhow. It's a Windows thing, but neither implementation should just drop-out without so much as a 'sorry'. The code is perfectly legal, if a bit of an edge case.

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Re^2: Signals in Strawberry Perl: Name or number?
by Marshall (Canon) on Sep 13, 2009 at 18:07 UTC
    On Windows XP, ActiveState 5.10 you will get:
    Process completed with exit code 14

    There is a problem with "kill", not with ALRM signal.

    And SIG INT works also! 

    #!/usr/bin/perl

use strict;
use warnings;

while (1)
{
  sleep(1);
}
__END__
Terminating on signal SIGINT(2)

Process completed with exit code 2

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    ....This was CTRL-Break....
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[d/l]

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