Compare the value of the uuid to the null value
#include <uuid.h> int uuid_is_null(uuid_t uu);
The uuid_is_null function compares the value of the supplied UUID variable uu to the NULL value. If the value is equal to the NULL UUID, 1 is returned, otherwise 0 is returned.
Theodore Y. Ts'o
libuuid is part of the util-linux package since version 2.15.1 and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.