sigaltstack
int sigaltstack(const stack_t * __restrict, stack_t * __restrict)
int sigaltstack(const struct sigaltstack13 * __restrict,
if (sigaltstack(&ss, NULL) != 0)
return sigaltstack(ss, oss);
struct sigaltstack ss;
RL(sigaltstack(&ss, NULL));
RL(sigaltstack(&ss, NULL));
struct sigaltstack *ssp;
RL(sigaltstack(&ss[nentries], NULL));
RL(sigaltstack(&ss[0], NULL));
struct sigaltstack ss[3];
ATF_REQUIRE(sigaltstack(&sigstk, 0) == 0);
ATF_REQUIRE(sigaltstack(&sig_stack, NULL) == 0);
ATF_REQUIRE(sigaltstack(&sig_stack, NULL) == 0);