server.cpp

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#include <stdio.h>
#include <stdlib.h>
#include <WINSOCK2.H>
#pragma comment (lib, "WS2_32")

void showcontent(char *buff);

int main(int argc, char **argv)
{
	WSADATA wsaData;
	if( WSAStartup(0x101, &wsaData) != 0 )
	{
		printf("Failed Initialization.\n");
		return 0;
	}

	if(argc!=2)
	{
		printf("Usage: server.exe [port]\n");
		return 0;
	}

	int port = atoi(argv[1]);

	SOCKET sListen = ::socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	if (sListen == INVALID_SOCKET)
	{
		printf("Failed socket()\n");
		return 0;
	}

	sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_port = htons(port);
	sin.sin_addr.S_un.S_addr = INADDR_ANY;

	if (::bind(sListen, (LPSOCKADDR)&sin, sizeof(sin)) == SOCKET_ERROR)
	{
		printf("Failed bind()\n");
		return 0;
	}

	if (::listen(sListen, 2) == SOCKET_ERROR)
	{
		printf("Failed listen()\n");
		return 0;
	}

	sockaddr_in remoteAddr;
	int nAddrLen = sizeof(remoteAddr);
	SOCKET sClient;
	char szText[] = "TCP Server is Connected!\n\n";
	char buff[1024] = {0};
	char toSend[1024] = {0};

	while (TRUE)
	{
		sClient = ::accept(sListen, (SOCKADDR*)&remoteAddr, &nAddrLen);
		if (sClient == INVALID_SOCKET)
		{
			printf("Failed accept()\n");
			continue;
		}
		printf("Somebody is connecting: %s\n", inet_ntoa(remoteAddr.sin_addr));

		::send(sClient, szText, strlen(szText), 0);
		

		int nRecv = ::recv(sClient, buff, sizeof(buff), 0);
		if (nRecv > 0)
		{

				buff[nRecv] = '\0';
				::closesocket(sClient);
				break;
		

		}

	}

	::closesocket(sListen);
 	showcontent(buff);
	return 0;

}

void showcontent(char *buff)
{
	char content[8];
	strcpy(content, buff);
	printf("%s", content);
}