在Ubuntu环境下进行C++网络编程，通常会使用套接字（socket）API。以下是一个简单的TCP服务器和客户端的示例，展示了如何在Ubuntu上使用C++进行网络编程。
首先，确保你已经安装了g++编译器和相关的库。如果没有安装，可以使用以下命令进行安装：
sudo apt update sudo apt install g++ 创建一个名为tcp_server.cpp的文件，并添加以下代码：
#include <iostream> #include <cstring> #include <sys/socket.h> #include <netinet/in.h> #include <unistd.h> #define PORT 8080 int main() { int server_fd, new_socket; struct sockaddr_in address; int opt = 1; int addrlen = sizeof(address); char buffer[1024] = {0}; const char* hello = "Hello from server"; // Creating socket file descriptor if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0) { perror("socket failed"); exit(EXIT_FAILURE); } // Forcefully attaching socket to the port 8080 if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt))) { perror("setsockopt"); exit(EXIT_FAILURE); } address.sin_family = AF_INET; address.sin_addr.s_addr = INADDR_ANY; address.sin_port = htons(PORT); // Forcefully attaching socket to the port 8080 if (bind(server_fd, (struct sockaddr*)&address, sizeof(address)) < 0) { perror("bind failed"); exit(EXIT_FAILURE); } if (listen(server_fd, 3) < 0) { perror("listen"); exit(EXIT_FAILURE); } if ((new_socket = accept(server_fd, (struct sockaddr*)&address, (socklen_t*)&addrlen)) < 0) { perror("accept"); exit(EXIT_FAILURE); } read(new_socket, buffer, 1024); std::cout << buffer << std::endl; send(new_socket, hello, strlen(hello), 0); std::cout << "Hello message sent\n"; close(new_socket); close(server_fd); return 0; } 创建一个名为tcp_client.cpp的文件，并添加以下代码：
#include <iostream> #include <sys/socket.h> #include <arpa/inet.h> #include <unistd.h> #include <string.h> #define PORT 8080 int main() { struct sockaddr_in serv_addr; int sock = 0; const char* hello = "Hello from client"; char buffer[1024] = {0}; if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) { std::cout << "\n Socket creation error \n"; return -1; } serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(PORT); // Convert IPv4 and IPv6 addresses from text to binary form if (inet_pton(AF_INET, "127.0.0.1", &serv_addr.sin_addr) <= 0) { std::cout << "\nInvalid address/ Address not supported \n"; return -1; } if (connect(sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0) { std::cout << "\nConnection Failed \n"; return -1; } send(sock, hello, strlen(hello), 0); std::cout << "Hello message sent\n"; read(sock, buffer, 1024); std::cout << "Server: " << buffer << std::endl; close(sock); return 0; } 使用g++编译服务器和客户端代码：
g++ -o tcp_server tcp_server.cpp g++ -o tcp_client tcp_client.cpp 运行服务器：
./tcp_server 在另一个终端运行客户端：
./tcp_client 你应该会看到服务器和客户端之间的通信。
如果你对UDP感兴趣，可以参考以下简单的UDP服务器和客户端示例。
#include <iostream> #include <sys/socket.h> #include <netinet/in.h> #include <unistd.h> #define PORT 8080 int main() { int sockfd; struct sockaddr_in servaddr, cliaddr; char buffer[1024] = {0}; if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { std::cout << "\n Socket creation error \n"; return -1; } memset(&servaddr, 0, sizeof(servaddr)); memset(&cliaddr, 0, sizeof(cliaddr)); servaddr.sin_family = AF_INET; servaddr.sin_addr.s_addr = INADDR_ANY; servaddr.sin_port = htons(PORT); bind(sockfd, (const struct sockaddr*)&servaddr, sizeof(servaddr)); int n; socklen_t len = sizeof(cliaddr); n = recvfrom(sockfd, (char*)buffer, 1024, MSG_WAITALL, (struct sockaddr*)&cliaddr, &len); buffer[n] = '\0'; std::cout << "Client message: " << buffer << std::endl; sendto(sockfd, (const char*)buffer, strlen(buffer), MSG_CONFIRM, (const struct sockaddr*)&cliaddr, len); close(sockfd); return 0; } #include <iostream> #include <sys/socket.h> #include <arpa/inet.h> #include <unistd.h> #include <string.h> #define PORT 8080 int main() { int sockfd; struct sockaddr_in servaddr; if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { std::cout << "\n Socket creation error \n"; return -1; } memset(&servaddr, 0, sizeof(servaddr)); servaddr.sin_family = AF_INET; servaddr.sin_port = htons(PORT); const char* hello = "Hello from UDP client"; sendto(sockfd, (const char*)hello, strlen(hello), MSG_CONFIRM, (const struct sockaddr*)&servaddr, sizeof(servaddr)); char buffer[1024] = {0}; int n = recvfrom(sockfd, (char*)buffer, 1024, MSG_WAITALL, (struct sockaddr*)&servaddr, NULL); buffer[n] = '\0'; std::cout << "Server reply: " << buffer << std::endl; close(sockfd); return 0; } 编译和运行UDP服务器和客户端的方法与TCP示例相同。
通过这些示例，你应该能够在Ubuntu环境下使用C++进行基本的网络编程。
