Question

基本上我想要做的是获取连接到服务器的客户端列表。我想

设置客户名称
在服务器中获取客户端名称

以下是代码： -

Server.c代码

/*A simple server. The port number is passed as an argument */

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

void error(char *msg)
{
    perror(msg);
    exit(1);
}

int main(int argc, char *argv[])
{
    int sockfd, newsockfd, portno, clilen;
    char buffer[256];
    struct sockaddr_in serv_addr, cli_addr;
    int n;

    if (argc < 2)
    {
        fprintf(stderr, "ERROR, no port provided\n");
        exit(1);    
    }

    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    if (sockfd < 0)
    {
        error("ERROR OPENING SOCKET");
    }

    bzero((char *) &serv_addr, sizeof(serv_addr));

    portno = atoi(argv[1]);

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = INADDR_ANY;
    serv_addr.sin_port = htons(portno);

    if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
    {
        error("ERROR ON BINDING");
    }

    listen(sockfd, 5);
    clilen = sizeof(cli_addr);  

    newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);



    if (newsockfd < 0)
    {
        error("ERROR ON ACCEPT");
    }


    bzero (buffer, 256);

    n = read(newsockfd, buffer, 255);

    if (n < 0)
    {
        error("ERROR READING FROM SOCKET");
    }
    printf("Following clients are connected:\n");

    printf("Here is the message: %s\n", buffer);


    n = write(newsockfd, "I got your message", 18);

    if (n < 0)
    {
        error("ERROR WRITING TO SOCKET");
    }



    return 0;
}

Client.c代码

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

void error(char *msg)
{
    perror(msg);
    exit(0);
}

int main(int argc, char *argv[])
{
    int sockfd, portno, n;
    struct sockaddr_in serv_addr;
    struct hostent *server;

/*
    int option = 0;
    char clientname[100];

    while( option != 3)
    {
        printf("If you want to see the list of clients press 1.\n");
        printf("If you want to chat with a certain client press 2 & enter its Name with message: ");

        scanf("%d", &option);

        if( option == 2)
        {   
            printf("Enter client name: ");
            scanf("%s", &clientname);
            option = 3;
        }
    }
*/


    char buffer[256];

    if (argc < 3)
    {
        fprintf(stderr,"usage %s hostname port\n", argv[0]);
        exit(0);    
    }

    portno = atoi(argv[2]);

    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    if (sockfd < 0)
    {
        error("ERROR OPENING SOCKET");
    }

    server = gethostbyname(argv[1]);
    if (server == NULL)
    {
        fprintf(stderr, "ERROR, no such host\n");
        exit(0);
    }

    bzero((char *) &serv_addr, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;

    bcopy((char *)server->h_addr,(char *)&serv_addr.sin_addr.s_addr, server->h_length);

    serv_addr.sin_port = htons(portno);

    if (connect(sockfd,&serv_addr,sizeof(serv_addr)) < 0)
    {
        error("ERROR CONNECTING");
    }

    printf("Please Enter a message: ");
    bzero(buffer,256);
    fgets(buffer,255,stdin);
    n = write(sockfd, buffer, strlen(buffer));
    if (n < 0)
    {
        error("ERROR writing to SOCKET");
    }
    bzero(buffer,256);
    n = read(sockfd,buffer,255);
    if (n < 0)
    {
        error("ERROR reading from SOCKET");
    }
    printf("%s\n", buffer);

    return 0;
}

我尝试在server.c中添加以下代码，但没有发生任何事情

    getpeername(newsockfd, (struct sockaddr*)&cli_addr, &clilen);

    struct sockaddr_in *newsockfd = (struct sockaddr_in *)&cli_addr;
    portno = ntohs(newsockfd->sin_port);
    inet_ntop(AF_INET, &newsockfd->sin_addr, ipstr, sizeof ipstr);


    printf("Peer IP address: %s\n", ipstr);
    printf("Peer port      : %d\n", portno);

在C中设置客户端名称和服务器中的客户端名称

0 个答案: