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

int main(int argc, char *argv[])
{
    /*取得main函数参数*/
    struct sockaddr_in address;//socket地址
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = inet_addr("127.0.0.1");
    address.sin_port = htons(6666);
    int len = sizeof(address);
    char send_buf[30] = "大家好，我是发送内容";//发送内容
    /*如果有参数，则以参数里的内容作为IP连接，如果无参数，则使用默认值*/
    if (argc != 4)
    {
        printf("*******************************************\r\n");
        printf("你输入的参数不全，正确的格式应该为：\r\n");
        printf("./sc_eth_com \"ip地址\" \"端口\" \"发送内容\"\r\n");
        printf("未输入的参数将使用默认值连接\r\n");
        printf("*******************************************\r\n");
    }
    if (argc > 1)
    {
        address.sin_addr.s_addr = inet_addr(argv[1]);
        if (address.sin_addr.s_addr == INADDR_NONE)
        {
            printf("IP地址格式错误，参数被强制转换为127.0.0.1\r\n");
            address.sin_addr.s_addr = inet_addr("127.0.0.1");
        }
    }
    if (argc > 2)
    {
        address.sin_port = htons((unsigned short)atoi(argv[2]));
    }
    if (argc > 3)
    {
        strncpy(send_buf, argv[3], 29);
        send_buf[29] = '\0';
    }

    /*展示所有参数*/
    char port_str[6] = {0};
    sprintf(port_str, "%d", ntohs(address.sin_port));
    printf("参数值 >>> IP地址：%s\r\n", inet_ntoa(address.sin_addr));
    printf("参数值 >>> 端口号：%s\r\n", port_str);
    printf("参数值 >>> 发送内容：[%s]\r\n", send_buf);

    #if 1
    if (write(5, send_buf, strlen(send_buf)+1) < 0)
    {
        perror("随便一个write");//这里不会退出
    }
    #endif

    /*打开一个套接字*/
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0)
    {
        perror("创建socket套接字失败");
    }
    printf("创建的套接字sockfd的值为[%d]\r\n", sockfd);

    #if 1
    int retval;
    retval = write(sockfd, send_buf, 20);//程序在这里退出了
    if (retval < 1)
    {
        printf("发送内容失败\r\n");
    }
    else
    {
        printf("发送内容成功\r\n");
    }
    #endif

    /*开始连接*/
    retval = connect(sockfd, (struct sockaddr *)&address, len);
    if (retval == -1)
    {
        perror("连接服务器失败");
        printf("sockfd 为 [%d]\r\n", sockfd);
        //exit(-1);
    }

    printf("开始发送\r\n");
    while (1)
    {
        retval = write(sockfd, send_buf, 20);
        if (retval < 1)
        {
            printf("发送内容失败\r\n");
        }
        else
        {
            printf("发送内容成功\r\n");
        }
        sleep(1);
    }
    
    char recv_buf[20] = {0};
    while (1)
    {
        retval = recv(sockfd, recv_buf, 20, MSG_DONTWAIT);
        printf("接收内容 <<< [%s]\r\n长度为[%d]字节\r\n", recv_buf, retval);
        sleep(1);
    }
    close(sockfd);
    exit(0);
}

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#include <string.h>
#include <time.h>
#include <s