使用基于RT -Thread的W5500来写TCP客户端的程序

在applications文件下新建my_tcp.c文件
#include
#include /* 使用BSD socket，需要包含socket.h头文件 */
#include
#include
#include
#define BUFSZ 1024
static const char send_data[] = "This is TCP Client from RT-Thread."; /* 发送用到的数据 */
void tcpclient(int argc, char **argv)
{
int ret;
char *recv_data;
struct hostent *host;
int sock, bytes_received;
struct sockaddr_in server_addr;
const char *url;
int port;
if (argc < 3)
{
      rt_kprintf("Usage: tcpclient URL PORTn");
      rt_kprintf("Like: tcpclient 192.168.12.44 5000n");
      return ;
}
url = argv[1];
port = strtoul(argv[2], 0, 10);
/* 通过函数入口参数url获得host地址（如果是域名，会做域名解析） */
host = gethostbyname(url);
/* 分配用于存放接收数据的缓冲 */
recv_data = rt_malloc(BUFSZ);
if (recv_data == RT_NULL)
{
      rt_kprintf("No memoryn");
      return;
}
/* 创建一个socket，类型是SOCKET_STREAM，TCP类型 */
if ((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1)
{
      /* 创建socket失败 */
      rt_kprintf("Socket errorn");
      /* 释放接收缓冲 */
      rt_free(recv_data);
      return;
}
/* 初始化预连接的服务端地址 */
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port);
server_addr.sin_addr = *((struct in_addr *)host->h_addr);
rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
/* 连接到服务端 */
if (connect(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)) == -1)
{
      /* 连接失败 */
      rt_kprintf("Connect fail!n");
      closesocket(sock);
      /*释放接收缓冲 */
      rt_free(recv_data);
      return;
}
while (1)
{
      /* 从sock连接中接收最大BUFSZ - 1字节数据 */
      bytes_received = recv(sock, recv_data, BUFSZ - 1, 0);
      if (bytes_received < 0)
      {
         /* 接收失败，关闭这个连接 */
         closesocket(sock);
         rt_kprintf("nreceived error,close the socket.rn");
         /* 释放接收缓冲 */
         rt_free(recv_data);
         break;
      }
      else if (bytes_received == 0)
      {
         /* 默认 recv 为阻塞模式，此时收到0认为连接出错，关闭这个连接 */
         closesocket(sock);
         rt_kprintf("nreceived error,close the socket.rn");
         /* 释放接收缓冲 */
         rt_free(recv_data);
         break;
      }
      /* 有接收到数据，把末端清零 */
      recv_data[bytes_received] = '';
      if (strncmp(recv_data, "q", 1) == 0 || strncmp(recv_data, "Q", 1) == 0)
      {
         /* 如果是首字母是q或Q，关闭这个连接 */
         closesocket(sock);
         rt_kprintf("n got a 'q' or 'Q',close the socket.rn");
         /* 释放接收缓冲 */
         rt_free(recv_data);
         break;
      }
      else
      {
         /* 在控制终端显示收到的数据 */
         rt_kprintf("nReceived data = %s ", recv_data);
      }
      /* 发送数据到sock连接 */
      ret = send(sock, send_data, strlen(send_data), 0);
      if (ret < 0)
      {
         /* 接收失败，关闭这个连接 */
         closesocket(sock);
         rt_kprintf("nsend error,close the socket.rn");
         rt_free(recv_data);
         break;
      }
      else if (ret == 0)
      {
         /* 打印send函数返回值为0的警告信息 */
         rt_kprintf("n Send warning,send function return 0.rn");
      }
}
return;
}
MSH_CMD_EXPORT(tcpclient, a tcp client sample);
我也是直接复制过来的
然后在电脑上建立一个TCP服务器，电脑需要和W5500的网络在同一个局域网内
我的电脑IP地址是192.168.1.80服务器端口号是8000