Older versions of perl (such as 5.005) don't understand -CO, nor
do they understand the "U" pack specifier. Instead of using perl,
let's just printf the binary bytes we are interested in.
Signed-off-by: Jeff King <peff@peff.net> Tested-by: Johannes Sixt <johannes.sixt@telecom.at> Signed-off-by: Junio C Hamano <gitster@pobox.com>