C-socket編程-客戶端服務端通信模型

服務端代碼

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>

int main()
{
    //創建套接字
    int serv_sock = socket(AF_INET,SOCK_STREAM,0);
    //將套接字與IP,PORT綁定

    //創建sokaddr_in結構體，並經行本地字節序和網絡字節序的轉換
    struct sockaddr_in serv_addr;
    memset(&serv_addr,0,sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
    serv_addr.sin_port = htons(1234);

    bind(serv_sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr));

    //進入監聽狀態，等待用戶發起請求
    listen(serv_sock,20);

    //接收客戶端請求
    struct sockaddr_in clnt_addr;
    socklen_t clnt_addr_size =sizeof(clnt_addr);
    int clnt_sock=accept(serv_sock,(struct sockaddr *)&clnt_addr,&clnt_addr_size);

    char buf[4096];
    int n,i;
    while(1)
    {
        n=read(clnt_sock,buf,sizeof(buf));
        for(i=0;i<n;i++)
        {
            buf[i]=toupper(buf[i]);
        }
        write(clnt_sock,buf,n);
    }

    //關閉套接字
    close(clnt_sock);
    close(serv_sock);

    return 0;






}

客戶端代碼

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

int main(){
    //創建套接字
    int sock = socket(AF_INET, SOCK_STREAM, 0);
    //向服務器（特定的IP和端口）發起請求
    struct sockaddr_in serv_addr;
    memset(&serv_addr, 0, sizeof(serv_addr));  //每個字節都用0填充
    serv_addr.sin_family = AF_INET;  //使用IPv4地址
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");  //具體的IP地址
    serv_addr.sin_port = htons(1234);  //端口
    connect(sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr));


    char buf[4096];
    int n;
    while(1)
    {
    fgets(buf,sizeof(buf),stdin);
    write(sock,buf,strlen(buf));
    n=read(sock,buf,sizeof(buf));
    printf("Message form server: %s\n", buf);
    }

    //關閉套接字
    close(sock);
    return 0;
}