$debug = 1; # toggle to 0 to turn off debug
if ($debug) {
    open(FH, ">-") or die "Unable to open STDOUT: $!\n";
} else {
    open(FH, ">/tmp/var/$0$$.log") or die "Unable to open $0$$.log $!\n";
}

print FH "If \$debug = 1 this will print to log otherwise print to the screen(STDOUT)\n";