sub handler {       # 1st argument is signal name
    local($sig) = @_;
    print "Caught a SIG$sig--shutting down\n";
    close(LOG);
    exit(0);
}

$SIG{INT} = 'handler';
$SIG{QUIT} = 'handler';
...
$SIG{INT} = 'DEFAULT';    # restore default action
$SIG{QUIT} = 'IGNORE';    # ignore SIGQUIT