winsock vc学习-01-简单client-ECHO

uatlaosiji

记录最基础的socket-client代码
直接复制vs进入不用设置。

[C++] 纯文本查看 复制代码

// winsock_01.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <winsock2.h>
#include <ws2tcpip.h>



#pragma comment(lib, "Ws2_32.lib")

#define DEFAULT_PORT "27015"


int main(int argc,char **argv) {
        WSADATA wsaData;

        int iResult;

        // Initialize Winsock
        iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
        if (iResult != 0) {
                printf("WSAStartup failed: %d\n", iResult);
                return 1;
        }


        struct addrinfo *result = NULL,
                *ptr = NULL,
                hints;

        ZeroMemory(&hints, sizeof(hints));
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        hints.ai_protocol = IPPROTO_TCP;


        // Resolve the server address and port
        iResult = getaddrinfo(argv[1], DEFAULT_PORT, &hints, &result);
        if (iResult != 0) {
                printf("getaddrinfo failed: %d\n", iResult);
                WSACleanup();
                return 1;
        }

        SOCKET ConnectSocket = INVALID_SOCKET;


        // Attempt to connect to the first address returned by
        // the call to getaddrinfo
        ptr = result;

        // Create a SOCKET for connecting to server
        ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype,
                ptr->ai_protocol);

        if (ConnectSocket == INVALID_SOCKET) {
                printf("Error at socket(): %ld\n", WSAGetLastError());
                freeaddrinfo(result);
                WSACleanup();
                return 1;
        }

        // Connect to server.
        iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
        if (iResult == SOCKET_ERROR) {
                closesocket(ConnectSocket);
                ConnectSocket = INVALID_SOCKET;
        }

        // Should really try the next address returned by getaddrinfo
        // if the connect call failed
        // But for this simple example we just free the resources
        // returned by getaddrinfo and print an error message

        freeaddrinfo(result);

        if (ConnectSocket == INVALID_SOCKET) {
                printf("Unable to connect to server!\n");
                WSACleanup();
                return 1;
        }

#define DEFAULT_BUFLEN 512

        int recvbuflen = DEFAULT_BUFLEN;

        char *sendbuf = "this is a test";
        char recvbuf[DEFAULT_BUFLEN];

        
        // Send an initial buffer
        iResult = send(ConnectSocket, sendbuf, (int)strlen(sendbuf), 0);
        if (iResult == SOCKET_ERROR) {
                printf("send failed: %d\n", WSAGetLastError());
                closesocket(ConnectSocket);
                WSACleanup();
                return 1;
        }

        printf("Bytes Sent: %ld\n", iResult);

        // shutdown the connection for sending since no more data will be sent
        // the client can still use the ConnectSocket for receiving data
        iResult = shutdown(ConnectSocket, SD_SEND);
        if (iResult == SOCKET_ERROR) {
                printf("shutdown failed: %d\n", WSAGetLastError());
                closesocket(ConnectSocket);
                WSACleanup();
                return 1;
        }

        // Receive data until the server closes the connection
        do {
                iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
                if (iResult > 0)
                        printf("Bytes received: %d\n", iResult);
                else if (iResult == 0)
                        printf("Connection closed\n");
                else
                        printf("recv failed: %d\n", WSAGetLastError());
        } while (iResult > 0);

        // shutdown the send half of the connection since no more data will be sent
        iResult = shutdown(ConnectSocket, SD_SEND);
        if (iResult == SOCKET_ERROR) {
                printf("shutdown failed: %d\n", WSAGetLastError());
                closesocket(ConnectSocket);
                WSACleanup();
                return 1;
        }

        // cleanup
        closesocket(ConnectSocket);
        WSACleanup();

        return 0;
 
}

慵懒丶L先森

没有注释，不好的习惯