Hands-On System Programming with Linux

Example code snippet showing the workflow

In the following, we display code snippets from our sample program ch13/react.c (see more on this rather interesting reaction time game app in the following section), which clearly illustrates the sequence of steps previously described.

• Signal(s) set up:
  • Assuming the notification mechanism being used is a signal, first trap the signal(s) via sigaction(2) as follows:

struct sigaction act;[...]// Trap SIGRTMIN : delivered on (interval) timer expirymemset(&act, 0, sizeof(act));act.sa_flags = SA_SIGINFO | SA_RESTART;act.sa_sigaction = timer_handler;if (sigaction(SIGRTMIN, &act, NULL) == -1)    FATAL("sigaction SIGRTMIN failed\n");

• Create and initialize the timer(s):
  • Decide on the clock type (or source) ...