also, add the following in your server where you handle the QUIT case:

my $ret = $client_socket->shutdown(2);
if( ! defined($ret) ){ print STDERR "$0 : error shutdown() : not a val
+id filehandle.\n"; }
elsif( $ret == 0 ){ print STDERR "$0 : error shutdown() : $!\n"; }
else { print "$0 : socket shutdown OK\n"; }
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