#include <errno.h>
#include <signal.h>

int sigwait(const sigset_t *restrict mask, int *restrict sig)
{
	int ret;
	siginfo_t si;
	do ret = sigtimedwait(mask, &si, 0);
	while (ret<0 && errno==EINTR);
	if (ret<0) return -1;
	*sig = si.si_signo;
	return 0;
}