---

#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main() {
    int fd1[2], fd2[2]; // fd1: parent->child, fd2: child->parent
    int result;
    char buffer[100];
    ssize_t size;

    if (pipe(fd1) < 0 || pipe(fd2) < 0) {
        printf("Can't create pipe\n");
        exit(1);
    }

    result = fork();

    if (result < 0) {
        printf("Can't fork child\n");
        exit(1);
    } 
    else if (result > 0) { // Родитель
        close(fd1[0]); // не читаем из fd1
        close(fd2[1]); // не пишем в fd2

        write(fd1[1], "Hello from parent", 18);

        size = read(fd2[0], buffer, sizeof(buffer) - 1);
        buffer[size] = '\0';
        printf("Parent received: %s\n", buffer);

        close(fd1[1]);
        close(fd2[0]);
    } 
    else { // Ребёнок
        close(fd1[1]); // не пишем в fd1
        close(fd2[0]); // не читаем из fd2

        size = read(fd1[0], buffer, sizeof(buffer) - 1);
        buffer[size] = '\0';
        printf("Child received: %s\n", buffer);

        write(fd2[1], "Hello from child", 17);

        close(fd1[0]);
        close(fd2[1]);
    }

    return 0;
}