To handle interrupts:

Question

In the following program:

Ctrl+z and ctrl+c both are interrupts.
The code is supposed to handle any interrupt.


Then why does only one of them(ctrl+c) work?

Code:

#include <signal.h>
#include<stdio.h>
void handler(int sig)
{
    printf("Caught SIGINT\n");
    exit(0);
}

int main() 
{
    printf("\nYou can press ctrl+c to test this program\n");
    if (signal(SIGINT, handler) == SIG_ERR) 
    perror("signal error");

    pause(); /* wait for the receipt of a signal */

    exit(0);
}

Input by the user: has to be an interrupt Output must be: Caught sigint

Answer 1

Ctrl-Z sends SIGTSTP.

Things to read:

• http://en.wikipedia.org/wiki/Control-Z
• http://en.wikipedia.org/wiki/SIGTSTP#SIGTSTP

Answer 2

Because Ctrl-Z causes a SIGTSTP, not a SIGINT.