7a) TCP Client-Server Communication (Ubuntu/Linux)

Files:
- server.cpp (TCP Server)
- client.cpp (TCP Client)

-----------------------------------------------------------------
SERVER (server.cpp):

#include <iostream>
#include <unistd.h>
#include <arpa/inet.h>
using namespace std;

int main() {
    int serverSocket = socket(AF_INET, SOCK_STREAM, 0);

    sockaddr_in serverAddr{};
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_addr.s_addr = INADDR_ANY;
    serverAddr.sin_port = htons(8080);

    bind(serverSocket, (sockaddr*)&serverAddr, sizeof(serverAddr));
    listen(serverSocket, 1);

    cout << "Waiting for client..." << endl;
    int clientSocket = accept(serverSocket, nullptr, nullptr);

    char buffer[1024] = {0};
    read(clientSocket, buffer, sizeof(buffer));
    cout << "Message from client: " << buffer << endl;

    close(clientSocket);
    close(serverSocket);
    return 0;
}


-----------------------------------------------------------------
CLIENT (client.cpp):

#include <iostream>
#include <unistd.h>
#include <arpa/inet.h>
using namespace std;

int main() {
    int clientSocket = socket(AF_INET, SOCK_STREAM, 0);

    sockaddr_in serverAddr{};
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
    serverAddr.sin_port = htons(8080);

    connect(clientSocket, (sockaddr*)&serverAddr, sizeof(serverAddr));

    string message = "Hello, server!";
    send(clientSocket, message.c_str(), message.size(), 0);

    close(clientSocket);
    return 0;
}

--------------------------------------------------------------------
Terminal Command (Ubuntu):
1) g++ server.cpp -o server
2) ./server

Terminal Command (Ubuntu):
1) g++ client.cpp -o client
2) ./client