extern void binmemmove(void *dest,int dest_off,void *src,int src_off,size_t size);
extern size_t binwrite(int dest_fd,void *src,int src_off,size_t size);
extern size_t binread(void *dest,int dest_off,int src_fd,size_t size);
extern void binzero(void *dest,size_t size);
extern void negateblock(HsWord32 *dest,size_t size);