Simple Network Socket Guessing Game

[Fur Zi]

Hello, here is a very simple network socket game that lets client guess the random number generated in the server. No error checking or advance features. You can however learn from it or improvise it yourself.

_server.cpp

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <cstring>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <cerrno>
#include <fcntl.h>

int main()
{
    srand(time(NULL));
    int number = rand() % 100 + 1;
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0) {
        std::cerr << "Error creating socket: " << strerror(errno) << std::endl;
        return 1;
    }

    struct sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_port = htons(369);
    addr.sin_addr.s_addr = INADDR_ANY;
    if (bind(sockfd, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
        std::cerr << "Error binding socket: " << strerror(errno) << std::endl;
        return 1;
    }

    if (listen(sockfd, 5) < 0) {
        std::cerr << "Error listening on socket: " << strerror(errno) << std::endl;
        return 1;
    }

    int clientfd = accept(sockfd, NULL, NULL);
    if (clientfd < 0) {
        std::cerr << "Error accepting client: " << strerror(errno) << std::endl;
        return 1;
    }

    while (true)
    {
        char buffer[32] = {0};
        int n = read(clientfd, buffer, sizeof(buffer));
        int guess = atoi(buffer);

        const char* response;

        if (guess == number)
        {
            response = "You won!\n";
            write(clientfd, response, strlen(response));
            close(clientfd);
            break;
        }
        else if (guess < number)
            response = "Your guess is too low.\n";
        else
            response = "Your guess is too high.\n";

        write(clientfd, response, strlen(response));
    }

    close(sockfd);
    return 0;
}

_client.cpp

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <cerrno>
#include <fcntl.h>

int main()
{
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0) {
        std::cerr << "Error creating socket: " << strerror(errno) << std::endl;
        return 1;
    }

    struct sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_port = htons(369);
    addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    if (connect(sockfd, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
        std::cerr << "Error connecting to server: " << strerror(errno) << std::endl;
        return 1;
    }

    while (true)
    {
        std::cout << "Enter a guess: ";
        int guess;
        std::cin >> guess;

        char buffer[32];
        sprintf(buffer, "%d", guess);
        write(sockfd, buffer, strlen(buffer));

        memset(buffer, 0, sizeof(buffer));
        int n = read(sockfd, buffer, sizeof(buffer));
        std::cout << buffer;

        if (strstr(buffer, "You won") != NULL)
        {
            close(sockfd);
            break;
        }
    }

    return 0;
}