examples/PIPS/posixsignals/asyncSignal/src/sigusr2.c

/*
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Description: The source file for sigusr2 process.
*/


#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <e32def.h>

int gVal = TRUE;

void SIGUSR2_handler(int signum)
    {
    if(signum == SIGUSR2)
        {
        printf("Received the SIGUSR2 signal from the sigusr1 process after reading the file.\n");
        gVal = FALSE;
        }
    }

int main(int argc,char **argv)
    {
    pid_t asyProcsID;
    char ch;
    int ret;
    if(argc < 2)
        {
        printf("Please pass the correct arguments\n");
        return EXIT_FAILURE;
        }
    asyProcsID = atoi(argv[1]);  //The variable holding the sigusr1 process PID.
    // Setup the custom handler for SIGUSR2.
    signal(SIGUSR2, SIGUSR2_handler);
    printf("******************** In the sigusr2 process ********************\n");
    
    printf("\nPress the Enter key to send the SIGUSR1 signal to the sigusr1 process\n");
    getchar();
    ret = kill(asyProcsID,SIGUSR1);
    if(ret)
        {
        printf("kill() failed to send signal, errno=%d\n",errno);
        gVal = FALSE;
        }
    
    /* 
     Waiting until a SIGUSR2 signal is obtained from the sigusr1 process.
     This signal is sent after the aynscFile.txt file has been
     read and its content written to the console.
    */
    while(gVal)
        {
        sleep(0);   //Initiates signal handling.
        }
    printf("\nPress 'e'+Enter to exit from the sigusr2 process\n");
    while((ch = getchar())!= 'e')
        {
        if(ch == '\n')
            continue;
        else
            printf("The wrong option was selected, please try again!!!\n");
        }
    return EXIT_SUCCESS;
    }

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