Signal handling


 
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# 1  
Old 05-27-2009
Signal handling

I am trying to write a small program where I can send signals and then ask for an action to be triggered if that signal is received. For example, here is an example where I am trying to write a programme that will say you pressed ctrl*c when someone presses ctrl+c. My questions are what you would expect from a beginner so bear with me. First, how can I get ro test the functionality of my program? My udnerstanding is you get the process ID and then through kill -signalnumber PID you will be able to send the signal? For example kill -2 2345 to send teh SIGINT to PID 2345. But mine doesn't work. First I opened a new shell then used shellname & on the terminal to get the PID, then on the terminal wrote kill -2 2345 if the PID was that for example. But I always recieve '... No such process'. Where I am getting it wrong?
Code:
    #include <stdio.h>
    #include <stdlib.h>
    #include <errno.h>
    #include <signal.h>
    void signalhandler(int sig);

    int main(void)
    {
    char s[200];
    
        (void) signal (SIGINT, signalhandler);
    
                
        if (signal(SIGINT, signalhandler) == SIG_ERR) {
            perror("signal");
            exit(1);
        }
            return 0;
    }
    
            void signalhandler(int sig)
    {
        printf("You pressed CTRL+C!\n");
    }

# 2  
Old 05-27-2009
A usefull link regarding signal handling:

Signals

Regards
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