#include <WINSOCK2.H> #include <stdio.h> #define PORT 5150 #define MSGSIZE 1024 #pragma comment(lib, "ws2_32.lib") typedef struct { WSAOVERLAPPED overlap; WSABUF Buffer; char szMessage[MSGSIZE]; DWORD NumberOfBytesRecvd; DWORD Flags; SOCKET sClient; }PER_IO_OPERATION_DATA, *LPPER_IO_OPERATION_DATA; DWORD WINAPI WorkerThread(LPVOID); void CALLBACK CompletionROUTINE(DWORD, DWORD, LPWSAOVERLAPPED, DWORD); SOCKET g_sNewClientConnection; BOOL g_bNewConnectionArrived = FALSE; int main() { WSADATA wsaData; SOCKET sListen; SOCKADDR_IN local, client; DWORD dwThreadId; int iaddrSize = sizeof(SOCKADDR_IN); // Initialize Windows Socket library WSAStartup(0x0202, &wsaData); // Create listening socket sListen = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); // Bind local.sin_addr.S_un.S_addr = htonl(INADDR_ANY); local.sin_family = AF_INET; local.sin_port = htons(PORT); bind(sListen, (struct sockaddr *)&local, sizeof(SOCKADDR_IN)); // Listen listen(sListen, 3); // Create worker thread CreateThread(NULL, 0, WorkerThread, NULL, 0, &dwThreadId); while (TRUE) { // Accept a connection g_sNewClientConnection = accept(sListen, (struct sockaddr *)&client, &iaddrSize); g_bNewConnectionArrived = TRUE; printf("Accepted client:%s:%d ", inet_ntoa(client.sin_addr), ntohs(client.sin_port)); } } DWORD WINAPI WorkerThread(LPVOID lpParam) { LPPER_IO_OPERATION_DATA lpPerIOData = NULL; while (TRUE) { if (g_bNewConnectionArrived) { // Launch an asynchronous operation for new arrived connection lpPerIOData = (LPPER_IO_OPERATION_DATA)HeapAlloc( GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(PER_IO_OPERATION_DATA)); lpPerIOData->Buffer.len = MSGSIZE; lpPerIOData->Buffer.buf = lpPerIOData->szMessage; lpPerIOData->sClient = g_sNewClientConnection; WSARecv(lpPerIOData->sClient, &lpPerIOData->Buffer, 1, &lpPerIOData->NumberOfBytesRecvd, &lpPerIOData->Flags, &lpPerIOData->overlap, CompletionROUTINE); g_bNewConnectionArrived = FALSE; } SleepEx(1000, TRUE); //这里如果不sleep,根本不会进入完成例程的回调,第一个参数时间可以适当缩小 } return 0; } void CALLBACK CompletionROUTINE(DWORD dwError, DWORD cbTransferred, LPWSAOVERLAPPED lpOverlapped, DWORD dwFlags) { LPPER_IO_OPERATION_DATA lpPerIOData = (LPPER_IO_OPERATION_DATA)lpOverlapped; if (dwError != 0 || cbTransferred == 0) { // Connection was closed by client closesocket(lpPerIOData->sClient); HeapFree(GetProcessHeap(), 0, lpPerIOData); } else { lpPerIOData->szMessage[cbTransferred] = '