Re^3: Signals in Strawberry Perl: Name or number?

in reply to Re^2: Signals in Strawberry Perl: Name or number?
in thread Signals in Strawberry Perl: Name or number?

When I test code with ALRM signal, I fiddle with the alarm($num) parameter and often use sleep() to cause the alarm to "trigger" during testing. There are problems with signal handling...in general, there is no way to "safely" continue executing a process after an ALRM signal because many OS functions are not re-entrant or even re-startable by any means.

Update: I strike this last sentence because it upset some folks. No offense was intended. ~~I have no interest in obfuscated, obscure code although I do see that some folks have fun with this as an "art form".~~

The original question was, why doesn't this code work?

sub verse4 {
    my $boy;
    $SIG{ALRM} = sub { say "slip n slide" };
    ride( $boy ), kill (ALRM, $$) for (1 .. 3);
    sleep 1; map { $_++ } ($ice_cream, $cake);
}

sub ride { say "Whee!" };
[download]

Comment on Re^3: Signals in Strawberry Perl: Name or number? Download Code

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Re^4: Signals in Strawberry Perl: Name or number? by ikegami (Patriarch) on Sep 13, 2009 at 05:25 UTC
There's no difference between receiving an alarm that was sent via `alarm` or via `kill`. What makes you think that the latter can trigger signals when the former can't? What's obfuscated about sending a signal with `kill`, whose very purpose is to send signals?	[reply] [d/l] [select]
Re^5: Signals in Strawberry Perl: Name or number? by Marshall (Canon) on Sep 13, 2009 at 06:34 UTC
There's no difference between receiving an alarm that was sent via alarm or via kill. What makes you think that the latter can trigger signals when the former can't? I didn't say that there was a difference. I explained very clearly how to use the alarm signal in a normal application. A signal is a "message" from the OS. What's obfuscated about sending a signal with kill, whose very purpose is to send signals? What is obfuscated is this "poetry" idea and using language constructs in "unnatural ways". I have no problem with strange code as an art form.	[reply]
Re^6: Signals in Strawberry Perl: Name or number? by ikegami (Patriarch) on Sep 13, 2009 at 07:46 UTC
I didn't say that there was a difference. It looks like I misunderstood you. there is no way to "safely" continue executing a process after an ALRM signal because many OS functions are not [...] even re-startable by any means. What gives you that idea? What is obfuscated is this "poetry" idea Again, how is `kill ALRM, $$` obfuscation/poetry?	[reply] [d/l]

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