   #include <stdio.h>
   #include <stdlib.h>
   #include <fcntl.h>
   #include <unistd.h>
   
   #define DEVICE "/dev/pp"
   
   int main() {
     int ddfd = 0;
     int ret = 0;
     ddfd = open(DEVICE, O_RDWR);
     if (ddfd < 0) {
       printf("\nOpen of %s failed.\n", DEVICE);
       exit(-1);
     }
     printf("\nOpen of %s succeeded.\n", DEVICE);
   
     ret = close(ddfd);
     if (ret < 0) {
       printf("\nClosing %s failed.\n", DEVICE);
       exit(-1);
     }
     printf("\n Close of %s succeeded.\n", DEVICE);
     
     exit(0);
   }    
