Signals

C

Setting signal handlers

handle_fux is always of type void (*) (int).

struct sigaction sa;
sa.sa_handler = handle_fux;
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sigaction(SIGINT, &sa, NULL);

signal(SIGINT, handler_fux)

Masking signals

/* Prototype for the glibc wrapper function */
int sigprocmask(int how, const sigset_t *set, sigset_t *oldset);

about how:

SIG_BLOCK. The set of blocked signals is the union of the current set and the set argument.

SIG_UNBLOCK. The signals in set are removed from the current set of blockedsignals. It is permissible to attempt to unblock a signal whichis not blocked.

SIG_SETMASK. The set of blocked signals is set to the argument set.

sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask, SIGINT);
sigprocmask(SIG_BLOCK, &mask, NULL);

Suspending program until signal

sigset_t negmask;
sigfillset(&negmask);
sigdelset(&negmask, SIGINT);
sigsuspend(&negmask);

Bash

trap ctrl_c INT

function ctrl_c () {
    echo -e "\n\n[*] Quitting...\n"
    exit
}