Question

抱歉，我知道过去一天我一直在发布与同一主题相关的帖子，但我遇到了另一个问题。

server.cpp

/*Server */
#define _WIN32_WINNT 0x501
#include <iostream>
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
using namespace std;

const int winsock_version = 2;
#define PORT "3490"
#define MAX_NUM_CONNECTIONS 10

int main(void){

    WSADATA wsadata;

    if (WSAStartup(MAKEWORD(winsock_version,0),&wsadata) == 0){
        cout<<"-WSAStartup Initialized." << endl;

        struct addrinfo hints,*res;
        int sock_fd;

        memset(&hints,0,sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        hints.ai_flags = AI_PASSIVE;

        if (getaddrinfo(NULL,PORT,&hints,&res) != 0){
            cout<<"-Call to getaddress was unsucceful." << endl;
        }

        if( (sock_fd = socket(res->ai_family,res->ai_socktype,res->ai_protocol)) == -1){
            cout<<"-Unable to Create socket." << endl;
        }

        if ( (bind(sock_fd, res->ai_addr, res->ai_addrlen)) != -1 ){
            cout<<"-binding successful." << endl;
        }

        if ( (listen(sock_fd,MAX_NUM_CONNECTIONS)) != -1){
            cout<<"-Listening for incoming connections." << endl;
        }
        //-------------------------------------------------------------

        struct sockaddr_storage incming_info;
        socklen_t sin_size;
        sin_size = sizeof incming_info;

        int new_fd;

        new_fd = accept(sock_fd, (struct sockaddr*)&incming_info,&sin_size);
        if (new_fd == -1){
            cout<<"-Accepting error." << endl;
        }
        if(new_fd == INVALID_SOCKET){
            cout<<"-INVALID SOCKET ERROR." << endl;
        }
        //-------------------------------------------------------------

        cout<<"Connected?" << endl;
        char buffer[128];
        while(true){
            int ret_val;

            ret_val = recv(new_fd,buffer,sizeof(buffer),0);
            if(ret_val == -1){
                cout<<"Receiving Error." << endl;
                break;
            }else if(ret_val == 0){
                cout<<"Connection has been closed!." << endl;
                break;
            }else if(ret_val > 0){
                cout<<"Server: " << buffer<< endl;
            }
        }

        cout<<"-Closing connection" << endl;
        closesocket(new_fd);
    }else{
        cout<<"-WSAStartup Initialization failed." << endl;
        if(WSACleanup()!=0){
            cout<<"-WSACleanup Successful." << endl;
        }else{
            cout<<"-WSACleanup Failed." << endl;
        }
    }
    return 0;
}

client.cpp

/*client*/
#define _WIN32_WINNT 0x501
#include <iostream>
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
using namespace std;

#define PORT "3490"
#define SERVER "localhost"
const int winsockVersion = 2;


int main(void){

    WSADATA wsadata;
    if ( (WSAStartup(MAKEWORD(2,0),&wsadata)) == 0){
        cout<<"-WSAStartup Initialized." << endl;

        struct addrinfo hints, *res;
        int sockfd;

        memset(&hints,0,sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;

        if (getaddrinfo(SERVER,PORT,&hints,&res) != 0){
            cout<<"-getaddrinfo unsuccessful." << endl;
        }

        if ( (sockfd = socket(res->ai_family,res->ai_socktype,res->ai_protocol)) == -1 ){
            cout<<"-Unable to create socket." << endl;
        }

        if ( (connect(sockfd,res->ai_addr,res->ai_addrlen)) != -1 ){
            cout<<"-Connection Established." << endl;
        }

        cout<<"-Client connecting to: " << res->ai_addr << endl;

        while(true){
            char text_buff[128];
            cout<<"Enter text: ";
            cin>>text_buff;
            if( (send(sockfd,text_buff,sizeof(text_buff),0)) != -1 ){
                cout<<"-text_buff sent!." << endl;
                break;
            }
        closesocket(sockfd);

        }

    }else{
        cout<<"-WSAStartup Initialization failed." << endl;
        if(WSACleanup()!=0){
            cout<<"-WSACleanup Successful." << endl;
        }else{
            cout<<"-WSACleanup Failed." << endl;
        }
    }

    return 0;
}

我可以很好地运行服务器和客户端，但是我只能从客户端发送一个单词（由于某种原因无法发送一个句子），这个单词在服务器控制台上打印出来但是只要在服务器上打印出来控制台输出“接收错误”并关闭。

Answer 1

您不能认为对send()的单次调用就足够了（recv()也是如此）。您需要循环数据，直到发送/接收所有数据。

此外，您可能不希望总是发送128个字符，而应该只发送所需的长度（并在消息中设置终结符或前缀长度）。

Answer 2

尝试使用带有std :: string和std :: getline的char text_buff替换输入。

while( true )
{
   std::string line;
   std::cout << "Enter text: ";
   std::getline( cin, line );
   if( send( sockfd, text_buff.c_str(), text_buff.size(), 0 ) ) != -1 )
   {
      std::cout << "-text_buff sent!." << std::endl;
      break;
   }
   closesocket( sockfd );
}

我不确定你的循环，因为你似乎只是在第一次成功发送任何内容时退出。

Answer 3

两个问题
1. cin>>text_buff;只读到第一个空格。你可以使用std :: string 2. send(sockfd,text_buff,sizeof(text_buff),0)使用strlen(text_buff) + 1代替sizeof(text_buff) 如果使用std :: string，请尝试

string line;  
send(sockfd, line.c_str(),line.length()+1,0)

winsock客户端和服务器通信

3 个答案: