client_recv_file.cpp

#include <iostream>
#include <fstream>
#include <boost/asio.hpp>

using boost::asio::ip::tcp;

void start_receiving(tcp::socket& socket, const std::string& file_name) {
    std::ofstream file(file_name, std::ios::binary);
    if (!file.is_open()) {
        std::cerr << "Failed to open the file.\n";
        return;
    }

    boost::asio::streambuf buf;
    
    boost::asio::read(socket, buf);
    std::istream in_stream(&buf);
    file << in_stream.rdbuf();
}

int main() {
    try {
        boost::asio::io_service io_service;
        tcp::resolver resolver(io_service);
        tcp::resolver::query query("localhost", "1234");
        tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);

        tcp::socket socket(io_service);
        boost::asio::connect(socket, endpoint_iterator);

        start_receiving(socket, "received_file.txt");  
    } catch (std::exception& e) {
        std::cerr << "Exception: " << e.what() << "\n";
    }

    return 0;
}