Programming

    pid1 = fork();
    if (pid1 == -1) 
    { 
        perror("Can't create child\n");
        exit(1);
    }
    else 
        if (pid1 == 0) 
        {
            ppid=getppid();
            sprintf(ppidstr,"%d", ppid);
            if(execl("myprogram.exe","myprogram.exe",ppidstr) == -1)
                fprintf(stderr,"execl Error!\n");
            wait(NULL);//Wait until the parent opens myfifo
           printf("I am back to do some more stuff");
           exit();
        }
        else 
            {
                waitpid(0,NULL,0);//wait for the child's signal
                int fd = open(myfifo, O_WRONLY);
                write(fd, "Hi", sizeof("Hi"));
                    close(fd);
                  waitpid(0,NULL,0);//wait for the child's signal
                printf("My child ended ");
                exit(1);
            }

                int fd = open(myfifo, O_RDONLY);
                read(fd, buf, sizeof(buf));
                close(fd);
                   printf("PReceived: %s\n", buf);
                fd = open(myfifo, O_WRONLY);
                write(fd, "Hi", sizeof("Hi"));
                    close(fd);
                wait(NULL);
                printf("Me child ended ");
                exit(1);

    char * myfifo = "/cygdrive/c/a/progsys/tmp",buf[MAX_BUF];
    int ppid=atoi(argv[1]),fd;
    mkfifo(myfifo, 0666);
    printf("Doing stuff");
    fd = open(myfifo, O_WRONLY);
    write(fd, "Hid", sizeof("Hid"));
    close(fd);
    fd = open(myfifo, O_RDONLY);
    read(fd, buf, MAX_BUF);
    printf("CReceived: %s\n", buf);
    close(fd);

$ mkfifo xyz
$
$ cat < xyz

$ mkfifo xyz
$
$ cat < xyz
hello
$