scc

 1#include <signal.h>
 2#include <stddef.h>
 3
 4#include <arch/sigaction.h>
 5#include <sys.h>
 6
 7#undef signal
 8
 9void
10(*signal(int signum, void (*func)(int)))(int)
11{
12	struct sigaction osa, sa = {
13		.sa_handler = func,
14	};
15
16	if (_sigaction(signum, &sa, &osa) < 0)
17		return SIG_ERR;
18
19	return osa.sa_handler;
20}