hi when compiling mkyaffs2image tool , I add some debug message in function write_object_header: static int write_object_header(int id, enum yaffs_obj_type t, struct stat *s, int parent, const char *name, int equivalentObj, const char * alias) { ...... if(t == YAFFS_OBJECT_TYPE_FILE) { oh->file_size_low = s->st_size; oh->file_size_high = (s->st_size >> 32); printf("name=%s s->st_size:%lu file_size_low:%u file_size_hight=%u\n", oh->name, s->st_size, oh->file_size_low,oh->file_size_high); } ...... } then I got the debug info like this: Object 416, rootfs/bin/busybox is a file, name=busybox s->st_size:830472 file_size_low:830472 file_size_hight=830472 my question is why file_size_low is equal to file_size_hight ?? I use 32 bit linux systerm. BestRegards