Using %SIG to define our own signal handlers

   

#!/usr/bin/perl


use warnings;
use strict;

my $count = 3;
$| = 1;

$SIG{ 'INT' } = \&stop;

while ( $count ) {
   print( "Hi!" );
   print( "\n" );
   sleep( 1 );
}

sub stop 
{
   $SIG{ 'INT' } = \&stop;
   $count--;
   print( "$count\n" );

   unless ( $count ) {
      print( "line...\n" );
   }
}

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Using %SIG to define our own signal handlers : Special Variables « Language Basics « Perl

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