| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| |
| /* This flag controls termination of the main loop. */ |
| volatile sig_atomic_t keep_going = 1; |
| |
| /* The signal handler just clears the flag and re-enables itself. */ |
| void |
| catch_alarm (int sig) |
| { |
| keep_going = 0; |
| signal (sig, catch_alarm); |
| } |
| |
| void |
| do_stuff (void) |
| { |
| puts ("Doing stuff while waiting for alarm...."); |
| } |
| |
| int |
| main (void) |
| { |
| /* Establish a handler for SIGALRM signals. */ |
| signal (SIGALRM, catch_alarm); |
| |
| /* Set an alarm to go off in a little while. */ |
| alarm (2); |
| |
| /* Check the flag once in a while to see when to quit. */ |
| while (keep_going) |
| do_stuff (); |
| |
| return EXIT_SUCCESS; |
| } |