CHECK_SIGSETopt (oset), _NSIG / 8);
CHECK_SIGSET_NULL_OK (oset), _NSIG / 8);
__sigprocmask (how, set, oset)     int how;     const sigset_t *set;     sigset_t *oset;{  /* XXX The size argument hopefully will have to be changed to the     real size of the user-level sigset_t.  */  return INLINE_SYSCALL (rt_sigprocmask, 4, how, CHECK_SIGSET (set),			 CHECK_SIGSETopt (oset), _NSIG / 8);}