/* Convert between a lo24/hi integer-pair bitset and a sigset_t value.
** These macros are OS-dependent, and must be defined per-OS.
*/
#define make_sigset(maskp, hi, lo) (*(maskp)=(sigset_t)((hi)<<24)|(lo))
/* Not a procedure: */
#define split_sigset(mask, hip, lop) \
	((*(hip)=(((int)mask)>>24)&0xff), (*(lop)=(((int)mask)&0xffffff)))