Sigalrm (linux signal)

Question

I'm new to Linux signals. If a process initializes multiple timers, then how does a process know which SIGALRM belongs to which timer?

Answer 1

It depends how you set up your SIGALRM handler.

Consider also using not alarm but timer_create or even timerfd_create(2) (with poll).

If you call sigaction(2) with the SA_SIGINFO you get the siginfo_t which indirectly gives you the timer information.

Read also all about linux signals, and Advanced Linux Programming