sysfs__read_build_id
ret = sysfs__read_build_id(notes, &bid);
sysfs__read_build_id(path, &bid);
sysfs__read_build_id(filename, &bid);
if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
int sysfs__read_build_id(const char *filename, struct build_id *bid);
rc = sysfs__read_build_id("/sys/kernel/notes", &bid);