sigalrm
(void)signal(SIGALRM, sigalrm);
extern void sigalrm(int);
signal(SIGALRM, sigalrm);
signal(SIGALRM, sigalrm);
void sigalrm(int);
sa.sa_handler = sigalrm;
while (sigalrm == 0 && !force_update) {
static sig_atomic_t sigalrm;
sigalrm = 0;
sigalrm = 1;