ref: 3c2cec93a9475a27f854ac2541f69c4a7a0b3657
dir: /lib/c/target/posix/signal.c/
#include <stddef.h>
#include <signal.h>
#include <sys.h>
#undef signal
void
(*signal(int signum, void (*func)(int)))(int)
{
struct sigaction sa = {
.sa_handler = func,
};
if (_sigaction(signum, &sa, &sa) < 0)
return SIG_ERR;
return sa.sa_handler;
}