/**
 * TCP客户端通信基本流程
 * zhangyl 2018年12月13日
 */
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <iostream>
#include <string.h>

#define SERVER_ADDRESS "127.0.0.1"
#define SERVER_PORT 3000
#define SEND_DATA "helloworld"

int main(int argc, char* argv[])
{
 //1.创建一个socket
 int clientfd = socket(AF_INET, SOCK_STREAM, 0);
 if (clientfd == -1)
 {
 std::cout << "create client socket error." << std::endl;
 return -1;
 }

 //2.连接服务器
 struct sockaddr_in serveraddr;
 serveraddr.sin_family = AF_INET;
 serveraddr.sin_addr.s_addr = inet_addr(SERVER_ADDRESS);
 serveraddr.sin_port = htons(SERVER_PORT);
 if (connect(clientfd, (struct sockaddr *)&serveraddr, sizeof(serveraddr)) == -1)
 {
 std::cout << "connect socket error." << std::endl;
		close(clientfd);
 return -1;
 }

	//3. 向服务器发送数据
	int ret = send(clientfd, SEND_DATA, strlen(SEND_DATA), 0);
	if (ret != strlen(SEND_DATA))
	{
		std::cout << "send data error." << std::endl;
		close(clientfd);
		return -1;
	}
	
	std::cout << "send data successfully, data: " << SEND_DATA << std::endl;
	
	//4. 从客户端收取数据
	char recvBuf[32] = {0};
	ret = recv(clientfd, recvBuf, 32, 0);
	if (ret > 0) 
	{
		std::cout << "recv data successfully, data: " << recvBuf << std::endl;
	} 
	else 
	{
		std::cout << "recv data error, data: " << recvBuf << std::endl;
	}
	
	//5. 关闭socket
	//close(clientfd);
	//这里仅仅是为了让客户端程序不退出
	while (true) 
	{
		sleep(3);
	}

 return 0;
}