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What is the problem?

galileo (2)
Can someone tell me what is the problem?
What I want to do is to jump from signalhandler into signalhandler but just doesnt seem to work:

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int A, B;
int sighandler(int sig)
{
    if (sig==SIGUSR1) //its A called
    {
        printf("A: %i. \n",getpid());
        sleep(1);
        kill(B,SIGUSR2);
    }
    else if(sig==SIGUSR2) //its B called
    {
        printf("B: %i. \n",getpid());
        sleep(1);
        kill(A,SIGUSR1);
    }
}
int main(int argc, char** argv) {

    signal(SIGUSR1,sighandler);
    signal(SIGUSR2,sighandler);
    A=getpid();
    B=fork();

    if (getpid()==A)
    {
        kill(B,SIGUSR2);
        while(1) pause();

    }

    else if (getpid()==B)
    {
        while(1) pause();
    }
    return (EXIT_SUCCESS);
}


And the output is:

B: 17345.
A: 17343.
...And here its endless loop, nothing happens.
bluecoder (763)
why are't you returning from the function

int sighandler(int sig)


also with why are't you using switch case , statement . 

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int sighandler(int sig)
{
switch( sig ) 
{
case SIGUSR1:
                           .....
                         ....
case SIGUSR2:
                  ...
                  ...
}


why use while(1) pause .
Last edited on
galileo (2)
Sorry, the sighandler is not supposed to return int is should be void. But still my problem remains unsolved.
I dont think switch case is any better here (I just dont like it thats all), and while(1) pause makes the process wait until it gets a signal from somewhere.
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