How to handle Ctrl+C with <signal.h> - c

Question

I'm attempting communications between a user-level program and a kernel module. My user-level program starts a timer then goes to sleep and is woken up by the kernel module when the time is completed, then a message is printed.
The problem I'm having is if I Ctrl+C while the user-level program is sleeping, when the timer expires it still prints the message (which I don't want it to do). This is my first time using <signal.h> and I'm having trouble figuring out how to implement this. I found a website which said that SIGHUP is the signal that is sent when Ctrl+C is pressed, so I think I should implement some case for this signal in my sighandler() function, but I'm pretty lost at the moment on how to go about this. Here's what I've pieced together so far:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <fcntl.h>
#include <unistd.h>
void sighandler(int);
int main(int argc, char **argv) {
char line[256];
int lenNum, lenName;
struct sigaction action, oa;
int pFile, oflags;
pFile = open("/dev/mytimer", O_RDWR);
if (pFile < 0) {
fprintf (stderr, "mytimer module isn't loaded\n");
return 1;
}
// Setup signal handler
memset(&action, 0, sizeof(action));
action.sa_handler = sighandler;
action.sa_flags = SA_SIGINFO;
sigemptyset(&action.sa_mask);
sigaction(SIGIO, &action, NULL);
fcntl(pFile, F_SETOWN, getpid()); // process ID o owner saved to filp->f_owner
oflags = fcntl(pFile, F_GETFL);
fcntl(pFile, F_SETFL, oflags | FASYNC); // enable asynchronous notification
// Check if timer set
if (argc >= 4 && strcmp(argv[1], "-s") == 0) {
lenNum = strlen(argv[2]);
lenName = strlen(argv[3]);
char *ptr;
int i;
i = asprintf(&ptr, "%s %s %s", argv[1], argv[2], argv[3]);
write(pFile, ptr, i+1);
while (read(pFile, line, strlen(line)) != 0) { //257?
printf("%s", line);
}
free(ptr);
//printf("Sleep!\n");
pause();
printf("%s\n", argv[3]);
}
// List all active timers
else if (argc == 2 && strcmp(argv[1], "-l") == 0) {
char *ptr;
int i;
i = asprintf(&ptr, "%s 0", argv[1]);
write(pFile, ptr, i);
while (read(pFile, line, strlen(line)) != 0) {
printf("%s", line);
}
free(ptr);
}
close(pFile);
return 0;
}
// SIGIO handler
void sighandler(int signo) {
//printf("Awaken!\n");
/* maybe something like this?
if (signo == SIGHUP) {
// clear timer
} */
}
Any suggestions are greatly appreciated.