github.com/afumu/libc@v0.0.6/musl/src/signal/sigdelset.c (about)

     1  #include <signal.h>
     2  #include <errno.h>
     3  
     4  int sigdelset(sigset_t *set, int sig)
     5  {
     6  	unsigned s = sig-1;
     7  	if (s >= _NSIG-1 || sig-32U < 3) {
     8  		errno = EINVAL;
     9  		return -1;
    10  	}
    11  	set->__bits[s/8/sizeof *set->__bits] &=~(1UL<<(s&8*sizeof *set->__bits-1));
    12  	return 0;
    13  }