#include <signal.h>
-#include <stdlib.h>
void (*sigset(int sig, void (*handler)(int)))(int)
{
return SIG_ERR;
if (handler == SIG_HOLD) {
- if (sigaction(sig, NULL, &sa_old) < 0)
+ if (sigaction(sig, 0, &sa_old) < 0)
return SIG_ERR;
if (sigprocmask(SIG_BLOCK, &mask, &mask) < 0)
return SIG_ERR;