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Perl Signal Handler

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# 1  
Old 06-10-2010
Perl Signal Handler
I was working on some Perl code that does signal handling and I came across this one liner and wasn't sure what it was doing.

Code:
local $SIG{__DIE__} = sub {$! = 2; die $_[0];};

I think the first part of the anonymous subroutine is setting $! to 2, but I am not sure what the second part is doing. Can someone explain this to me.

Thanks
# 2  
Old 06-11-2010
Code:
perl -e ' 
         use POSIX;
         $!=EINTR; 
         print strerror $!;
         die $_[0];'
echo "  return code from perl =  $?"

Instead of using defined error numbers, the coder decided to use a signal number as the return code from the perl code. SIGINT (EINTR) == 2 on most systems.
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