Re: sending signal to self with kill on windows (updated);

Why wasn't the %INC handler called?

What the heck is an " %INC handler"?

Update: assuming you mean %SIG handler; I think this demonstrates that the Perl Windows sig emulation has code to prevent a process from attempting to signal itself:

C:\test>start /b perl -E"say $$; sleep 10000"

C:\test>192904

C:\test>perl -E"kill 21, 192904 or die $^E"
Terminating on signal SIGBREAK(21)

C:\test>perl -E"kill 21, $$ or say $^E; say 'ending';"
The parameter is incorrect
ending
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It doesn't make a great deal of sense to signal yourself to invoke a subroutine when you can just:

C:\test>perl -wE"$SIG{BREAK}=sub{ say 'BREAKing' }; &{$SIG{BREAK}}; sa
+y 'ending'; "
BREAKing
ending
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With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

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.

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Re^2: sending signal to self with kill on windows (recursive sig-handler) by LanX (Saint) on Dec 30, 2012 at 21:12 UTC
> I think this demonstrates that the Perl Windows sig emulation has code to prevent a process from attempting to signal itself: Definitely! I had this at one of my projects... My face and all my hairs went pale, when I realized that a young colleague of mine called warn within `$SIG{__WARN__}`-handler. As it turned out Perl was (since 5.8 IIRC) idiot proof. It locally resets signal handler redirections before calling them. My colleague insisted that I exaggerated, because she "tested" (i.e ran) it once before committing into production. Her warn did depend on an if clause and "production" meant a central module of a mod-perl environment... Cheers Rolf UPDATE: from warn `Most handlers must therefore make arrangements to actually display the warnings that they are not prepare +d to deal with, by calling "warn" again in the handler. Not +e that this is quite safe and will not produce an endless loop +, since "__WARN__" hooks are not called from inside one.` [download]	[reply] [d/l] [select]

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Re^2: sending signal to self with kill on windows (recursive sig-handler)
by LanX (Saint) on Dec 30, 2012 at 21:12 UTC

> I think this demonstrates that the Perl Windows sig emulation has code to prevent a process from attempting to signal itself:

Definitely! I had this at one of my projects...

My face and all my hairs went pale, when I realized that a young colleague of mine called warn within $SIG{__WARN__}-handler.

As it turned out Perl was (since 5.8 IIRC) idiot proof. It locally resets signal handler redirections before calling them.

My colleague insisted that I exaggerated, because she "tested" (i.e ran) it once before committing into production.

Her warn did depend on an if clause and "production" meant a central module of a mod-perl environment...

Cheers Rolf

UPDATE:

from warn

               Most handlers must therefore make arrangements to
               actually display the warnings that they are not prepare
+d to
               deal with, by calling "warn" again in the handler.  Not
+e that
               this is quite safe and will not produce an endless loop
+, since
               "__WARN__" hooks are not called from inside one.
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