You'll need to setup a signal handler to catch the ctrl-c. 
my $num_ctrlc = 0;
$SIG{'INT'} = sub {
    $num_ctrlc++;
    print "Got $num_ctrlc ctrl-c\n";
    exit if $num_ctrlc > 2;
};

# rest of program

[download]
The $SIG{'INT'} part creates a signal handler for 'interrupt' (control-c) with your code. In this case, a little sub that increments a global counter, prints a message, and exists if the counter is above a certain number

BTW, your while loop is only going to run once, since @a will contain ALL of STDIN on the first pass... Perhaps you meant something more like: 

while ($a = <STDIN>) {
    print $a;
}

[download]
HTH

/\/\averick
OmG! They killed tilly! You *bleep*!!

In reply to Re: quiting program by maverick
in thread quiting program by Anonymous Monk

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