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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