C语言网络编程客户端和服务器之间的通信（tcp）_mfc 客户端和服务器传送文件

客户端

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <string.h>
 
#define SERVPORT 5000
 
 
int main(int argc,char ** argv)
{
    int sockfd,n;
    struct sockaddr_in servaddr,cliaddr;
    char sendline[1000];//发送缓冲区大小
    char recvline[1000];
 
    if(argc != 2)
    {
        printf("usage:server address!\n");
        exit(0);
    }
 
    sockfd = socket(AF_INET,SOCK_STREAM,0);
 
    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(SERVPORT);
    servaddr.sin_addr.s_addr = inet_addr(argv[1]);
    
 
    connect(sockfd,(struct sockaddr *)&servaddr,sizeof(servaddr));
 
    while(fgets(sendline,1000,stdin) != NULL)
   
    {
        sendto(sockfd,sendline,strlen(sendline),0,
                      (struct sockaddr *)&servaddr,sizeof(servaddr));
        
 
        n = recvfrom(sockfd,recvline,1000,0,NULL,NULL);
        
 
        recvline[n] = '\0';
 
        fputs(recvline,stdout);
    }
    close(sockfd);
 
    return 0;
}

服务器

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>
 
#define SERVPORT 5000
 
int main()
{
    int listenfd, connfd, n;
    struct sockaddr_in servaddr, cliaddr;
    socklen_t clilen;
    char msg[1000];
 
    listenfd = socket(AF_INET, SOCK_STREAM, 0);
 
    bzero(&servaddr, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(SERVPORT);
    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
 
    bind(listenfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
 
    listen(listenfd, 100);
 
    while (1)  //多个客户端
    {
        clilen = sizeof(cliaddr);
 
        connfd = accept(listenfd, (struct sockaddr *)&cliaddr, &clilen);
 
        for (;;) //多次会话
        {
            n = recvfrom(connfd, msg, 1000, 0, (struct sockaddr *)&cliaddr, &clilen);
 
            if (0 == n)
            {
                printf("client offline!\n");
                break;
            }
 
            sendto(connfd, msg, n, 0, (struct sockaddr *)&cliaddr, sizeof(cliaddr));
 
            printf("--------------------------------\n");
 
            msg[n] = '\0';
 
            printf("received the following:\n");
 
            printf("%s\n", msg);
 
            printf("--------------------------------------\n");
        }
 
        close(connfd);
    }
 
    close(listenfd);
 
    return 0;
}