foobar.txt contents 6 characters: "foobar"

    1   int main()
    2   {
    3     int fd;
    4     char c;
    5   
    6     fd = open("foobar.txt", O_RDONLY, 0);
    7     if ( fork() == 0 ) {
    8       read(fd, &c, 1);
    9       exit(0);
   10     }
   11     wait(0);
   12     read(fd, &c, 1);
   13     printf("c = %c\n", c);
   14     exit(0);
   15   }