#include #include #include "syscall.h" int __sigaction(int, const struct sigaction *, struct sigaction *); void (*signal(int sig, void (*func)(int)))(int) { struct sigaction sa = { .sa_handler = func, .sa_flags = SA_RESTART }; if (__sigaction(sig, &sa, &sa) < 0) return SIG_ERR; return sa.sa_handler; }