宣告：大部分程式碼來自這篇部落格http://www.cnblogs.com/diligenceday/p/6241021.html， 感謝博主

 思路：

思路很重要呦~~~

socket詳細資訊，思路：http://www.cnblogs.com/renfanzi/p/5713054.html

基礎知識 

一個簡單的socket服務端和客戶端

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

#define PORT 7000
#define QUEUE 20
int conn;

using namespace std;

int main() {
    
 
//例項化socket物件：
    // AF_INET為地址簇，預設IPV4;
    // SOCK_STREAM為型別，預設為tcp
    // 0為協議，預設自動選擇合適協議
    int ss = socket(AF_INET, SOCK_STREAM, 0);
    // 建立一個struct
    struct sockaddr_in server_sockaddr;
    //結構體加入引數：埠和地址
    server_sockaddr.sin_family = AF_INET;
    server_sockaddr.sin_port = htons(PORT);
    server_sockaddr.sin_addr.s_addr 
 
= htonl(INADDR_ANY);
    //bind()
    if (bind(ss, (struct sockaddr *) &server_sockaddr, sizeof(server_sockaddr)) == -1) {
        perror("bind");
        exit(1);
    }
    //listen()
    if (listen(ss, QUEUE) == -1) {
        perror("listen");
        exit(1);
    }

    struct sockaddr_in client_addr;
    socklen_t length = sizeof(client_addr);
    
    //accept()
    //成功返回非負描述字，出錯返回-1
    conn = accept(ss, (struct sockaddr *) &client_addr, &length);
    
    if (conn < 0) {
        perror("connect");
        exit(1);
    }

    char buffer[1024];
    while (1) {
        memset(buffer, 0, sizeof(buffer));
        
        //read()
        int len = recv(conn, buffer, sizeof(buffer), 0);
        if (strcmp(buffer, "exit\n") == 0) break;
        printf("buffer: %s", buffer);
        //send()
        //必須要有返回資料， 這樣才算一個完整的請求
        send(conn, buffer, len, 0);
    }
    close(conn);
    close(ss);
    return 0;
}

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

#define MYPORT  7000
#define BUFFER_SIZE 1024

int main() {
    ///定義sockfd
    int sock_cli = socket(AF_INET, SOCK_STREAM, 0);

    ///定義sockaddr_in
    struct sockaddr_in servaddr;
    memset(&servaddr, 0, sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(MYPORT);  ///伺服器埠
    servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");  ///伺服器ip

    //連線伺服器，成功返回0，錯誤返回-1
    if (connect(sock_cli, (struct sockaddr *) &servaddr, sizeof(servaddr)) < 0) {
        perror("connect");
        exit(1);
    }

    char sendbuf[BUFFER_SIZE];
    char recvbuf[BUFFER_SIZE];
    while (fgets(sendbuf, sizeof(sendbuf), stdin) != NULL) {
        send(sock_cli, sendbuf, strlen(sendbuf), 0); ///傳送
        if (strcmp(sendbuf, "exit\n") == 0)
            break;
        recv(sock_cli, recvbuf, sizeof(recvbuf), 0); ///接收
        fputs(recvbuf, stdout);

        memset(sendbuf, 0, sizeof(sendbuf));
        memset(recvbuf, 0, sizeof(recvbuf));
    }

    close(sock_cli);
    return 0;
}

還沒寫完呢，下一步，1對多，多執行緒，非同步，開源庫，框架，等等...