C语言中socket模块、线程

socket编程

windows下TCP协议

测试环境基于Win10 x64，Visual Studio

服务端代码1. 初始化Winsock库；2. 创建套接字；3. 配置服务端地址；4. 绑定套接字；5. 监听连接；6. 接收连接；7. 发送数据给客户端；8. 关闭连接。

#define _CRT_SECURE_NO_WARNINGS 1#define _WINSOCK_DEPRECATED_NO_WARNINGS#include #include #pragma comment(lib, "ws2_32.lib")// 因为用到了Winsock库，所以需要引入这个lib文件int main(){// 初始化Winsock库WSADATA wsaData;if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)// 初始化Winsock库，保证正确加载和卸载库{printf("初始化Winsock失败\n");return 0;}// 创建套接字SOCKET serverSocket = socket(AF_INET, SOCK_STREAM, 0);// 0代表默认协议if (serverSocket == INVALID_SOCKET){printf("创建套接字失败\n");WSACleanup();return 0;}// 配置服务端地址struct sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_addr.s_addr = INADDR_ANY;// INADDR_ANY为通配地址，0.0.0.0serverAddr.sin_port = htons(8080);// 绑定套接字if (bind(serverSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR){printf("绑定失败\n");closesocket(serverSocket);WSACleanup();return 0;}// 监听连接if (listen(serverSocket, 10) == SOCKET_ERROR){printf("监听失败\n");closesocket(serverSocket);WSACleanup();return 1;}// 接收连接SOCKET clientSocket = accept(serverSocket, NULL, NULL);if (clientSocket == INVALID_SOCKET){printf("连接失败\n");closesocket(serverSocket);WSACleanup();}printf("连接已建立\n");// 发送数据给客户端const char* message = "Hello, I'm Server!";send(clientSocket, message, (int)strlen(message), 0);// 关闭套接字closesocket(clientSocket);closesocket(serverSocket);WSACleanup();return 1;}

客户端代码1. 初始化Winsock库；2. 创建套接字；3. 配置服务端地址；4. 连接到服务器；5. 发送数据；6. 接收服务端返回数据；7. 关闭套接字。

#define _CRT_SECURE_NO_WARNINGS 1#define _WINSOCK_DEPRECATED_NO_WARNINGS#include #include #pragma comment(lib, "ws2_32.lib")// 因为用到了Winsock库，所以需要引入这个lib文件int main(){// 初始化Winsock库WSADATA wsaData;if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {printf("初始化Winsock失败\n");return 1;}// 创建套接字SOCKET clientSocket = socket(AF_INET, SOCK_STREAM, 0);if (clientSocket == INVALID_SOCKET) {printf("创建套接字失败\n");WSACleanup();return 1;}// 配置服务端地址struct sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); // 服务端IP地址serverAddr.sin_port = htons(8080); // 服务端端口号// 连接到服务端if (connect(clientSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {printf("连接失败\n");closesocket(clientSocket);WSACleanup();return 1;}// 发送数据printf("已成功连接至服务器\n");// 接收服务端发送的数据char buffer[1024];int bytesRead = recv(clientSocket, buffer, sizeof(buffer), 0);if (bytesRead > 0) {buffer[bytesRead] = '\0';printf("服务器: %s\n", buffer);}// 关闭套接字closesocket(clientSocket);WSACleanup();return 1;}

windows下UDP协议

服务端1. 初始化Winsock库；2. 创建套接字；3. 配置服务端地址；4. 绑定套接字；5. 接收数据；6. 返回数据给客户端；7. 关闭套接字。

#define _CRT_SECURE_NO_WARNINGS 1#define _WINSOCK_DEPRECATED_NO_WARNINGS#include #include #pragma comment(lib, "ws2_32.lib")// 因为用到了Winsock库，所以需要引入这个lib文件int main(){// 初始化Winsock库WSADATA wsaData;if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)// 初始化Winsock库，保证正确加载和卸载库{printf("初始化Winsock失败\n");return 0;}// 创建套接字SOCKET serverSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);if (serverSocket == INVALID_SOCKET){printf("创建套接字失败\n");WSACleanup();return 0;}// 配置服务端地址struct sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_addr.s_addr = INADDR_ANY;// INADDR_ANY为通配地址，0.0.0.0serverAddr.sin_port = htons(8080);// 绑定套接字if (bind(serverSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR){printf("绑定失败\n");closesocket(serverSocket);WSACleanup();return 0;}// 接收数据char buffer[1024];struct sockaddr_in clientAddr;int clientAddrSize = sizeof(clientAddr);int bytesRead = recvfrom(serverSocket, buffer, sizeof(buffer), 0, (struct sockaddr*)&clientAddr, &clientAddrSize);if (bytesRead > 0){buffer[bytesRead] = '\0';printf("客户端： %s\n", buffer);// 发送数据给客户端const char* message = "Hello from server!";sendto(serverSocket, message, (int)strlen(message), 0, (struct sockaddr*)&clientAddr, sizeof(clientAddr));}// 关闭套接字closesocket(serverSocket);WSACleanup();return 1;}

客户端1. 初始化Winsock库；2. 创建套接字；3. 配置服务端地址；4. 发送数据给服务端；5. 接收服务端发送的数据；6. 关闭套接字。

#define _CRT_SECURE_NO_WARNINGS 1#define _WINSOCK_DEPRECATED_NO_WARNINGS#include #include #pragma comment(lib, "ws2_32.lib")// 因为用到了Winsock库，所以需要引入这个lib文件int main(){// 初始化Winsock库WSADATA wsaData;if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {printf("初始化Winsock失败\n");return 1;}// 创建套接字SOCKET clientSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);if (clientSocket == INVALID_SOCKET) {printf("创建套接字失败\n");WSACleanup();return 1;}// 配置服务端地址struct sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1"); // 服务端IP地址// serverAddr.sin_addr.s_addr = INADDR_BROADCAST;// 如果给其他主机发消息，用这个serverAddr.sin_port = htons(8080); // 服务端端口号，这里最好只用htons，因为它针对16位的主机字节，端口一般都是16位// 发送数据给服务端const char* message = "服务端你好，我是客户端！\n";sendto(clientSocket, message, strlen(message), 0, (struct sockaddr*)&serverAddr, sizeof(serverAddr));// 接收服务端发送的数据char buffer[1024];struct sockaddr_in fromAddr;int fromAddrSize = sizeof(fromAddr);int bytesRead = recvfrom(clientSocket, buffer, sizeof(buffer), 0, (struct sockaddr*)&fromAddr, &fromAddrSize);if (bytesRead > 0) {buffer[bytesRead] = '\0';printf("服务器: %s\n", buffer);}// 关闭套接字closesocket(clientSocket);WSACleanup();return 1;}

贴一个自己项目当中用到的实例，该代码是用来和另一台主机通信的，通信要求如下1. 目标设备接收数据的端口是65001；2. 目标设备接收到数据后会有返回；3. 目标设备只接收18个字节的数据包；4. 目标设备只接收从65000端口发的数据，并且后续返回的数据也会返回到65000端口

#define _WINSOCK_DEPRECATED_NO_WARNINGS#include #include #pragma comment(lib, "ws2_32.lib") // 链接到Winsock库#define ENTER_CODE 0xEB90149Fint main() {WSADATA wsaData;SOCKET udpSocket;// 初始化Winsockif (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {printf("初始化 Winsock 失败.\n");return -1;}// 创建UDP套接字udpSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);if (udpSocket == INVALID_SOCKET) {printf("创建 socket 失败 : %d\n", WSAGetLastError());WSACleanup();return -1;}// 设置广播int on = 1;setsockopt(udpSocket, SOL_SOCKET, SO_BROADCAST, (char*)&on, sizeof(on));// 设置本地地址struct sockaddr_in localaddr;memset((char*)&localaddr, 0, sizeof(localaddr));localaddr.sin_family = AF_INET;localaddr.sin_port = htons(65000);localaddr.sin_addr.s_addr = inet_addr("192.168.10.1");// 将套接字绑定到本地地址if (bind(udpSocket, (struct sockaddr*)&localaddr, sizeof(localaddr)) == SOCKET_ERROR) {printf("绑定失败， error code : %d\n", WSAGetLastError());}// 设置服务器地址struct sockaddr_in serverAddr;int serverAddrSize = sizeof(serverAddr);memset((char*)&serverAddr, 0, sizeof(serverAddr));serverAddr.sin_family = AF_INET;serverAddr.sin_addr.s_addr = INADDR_BROADCAST;serverAddr.sin_port = htons(65001);// 将数据填充到buff中，注意网络字节序的转换unsigned char send_buff[200] = {0x00};int a = ENTER_CODE;memcpy(send_buff, &a, 4);// 为数据接收做准备unsigned char recv_buff[1072];struct sockaddr_in clientAddr;int clientAddrSize = sizeof(clientAddr);int recvSize;memset(recv_buff, 0, sizeof(recv_buff));while (1){// 发送数据sendto(udpSocket, (char*)send_buff, 18, 0, (struct sockaddr*)&serverAddr, serverAddrSize);if (sendto(udpSocket, (char *)send_buff, 18, 0, (struct sockaddr*)&serverAddr, serverAddrSize) == SOCKET_ERROR) {printf("数据发送失败， error code : %d\n", WSAGetLastError());}else { printf("发送成功 "); }for (int i = 0; i < 10; i++){printf(" %02X ", send_buff[i]);}printf("\n");Sleep(500);recvSize = recvfrom(udpSocket, (char*)recv_buff, sizeof(recv_buff), 0, (struct sockaddr*)&clientAddr, &clientAddrSize);if (recvSize == SOCKET_ERROR) {printf("接收数据失败， error code : %d\n", WSAGetLastError());}else if (recvSize > 0) {printf("接收到的数据: ");for (int i = 0; i < recvSize; i++) {printf("%02X ", recv_buff[i]);}printf("\n");}}// 清理closesocket(udpSocket);WSACleanup();return 0;}

进程和线程

Windows下多线程

#define _CRT_SECURE_NO_WARNINGS 1#include #include #include DWORD WINAPI threadFunction(LPVOID lpParam){int flag = 0;while (1){printf("线程功能\n");if (flag > 10) { break; }else { flag += 1; }Sleep(100);}return 0;}DWORD WINAPI threadFunction2(LPVOID lpParam){int flag = 0;while (1){printf("线程功能2222222\n");if (flag > 15) { break; }else { flag += 1; }Sleep(100);}return 0;}int main(){HANDLE t1;// 创建句柄HANDLE t2;// 创建句柄/*LPVOID pParam1;// 参数指针LPVOID pParam2;// 参数指针*/// 创建线程t1 = CreateThread(NULL,// 默认安全性,在大多数情况下，这个参数设置为NULL0,// 指定线程的堆栈大小,如果这个参数设为0，那么系统会为新线程分配默认的堆栈大小threadFunction,// 是一个函数指针，指向线程要执行的代码NULL,// 线程函数的参数0,// 指定如何创建线程,这个参数被设置为0，这意味着线程将立即开始执行NULL// 这个参数是一个输出参数，它接收新线程的ID);// 创建线程2t2 = CreateThread(NULL,// 默认安全性,在大多数情况下，这个参数设置为NULL0,// 指定线程的堆栈大小,如果这个参数设为0，那么系统会为新线程分配默认的堆栈大小threadFunction2,// 是一个函数指针，指向线程要执行的代码NULL,// 线程函数的参数0,// 指定如何创建线程,这个参数被设置为0，这意味着线程将立即开始执行NULL// 这个参数是一个输出参数，它接收新线程的ID);if (t1 == NULL | t2 == NULL){printf(stderr, "线程创建失败\n");return 0;}// 等待线程结束WaitForSingleObject(t1, INFINITE);WaitForSingleObject(t2, INFINITE);// 关闭线程句柄CloseHandle(t1);CloseHandle(t2);return 1;}