Server

#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include "conio.h"

#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")

#define SERVER_PORT 27016
#define BUFFER_SIZE 256

// TCP server that use blocking sockets
int main()
{
    // Socket used for listening for new clients
    SOCKET listenSocket = INVALID_SOCKET;

    // Socket used for communication with client
    SOCKET acceptedSocket = INVALID_SOCKET;
	int n=0;
    // Variable used to store function return value
    int iResult;

    // Buffer used for storing incoming data
    char dataBuffer[BUFFER_SIZE];

	// WSADATA data structure that is to receive details of the Windows Sockets implementation
    WSADATA wsaData;

	// Initialize windows sockets library for this process
    if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0)
    {
        printf("WSAStartup failed with error: %d\n", WSAGetLastError());
        return 1;
    }


	// Initialize serverAddress structure used by bind
	sockaddr_in serverAddress;
    memset((char*)&serverAddress,0,sizeof(serverAddress));
    serverAddress.sin_family = AF_INET;				// IPv4 address family
    serverAddress.sin_addr.s_addr = INADDR_ANY;		// Use all available addresses
    serverAddress.sin_port = htons(SERVER_PORT);	// Use specific port


    // Create a SOCKET for connecting to server
    listenSocket = socket(AF_INET,      // IPv4 address family
                          SOCK_STREAM,  // Stream socket
                          IPPROTO_TCP); // TCP protocol

	// Check if socket is successfully created
    if (listenSocket == INVALID_SOCKET)
    {
        printf("socket failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    // Setup the TCP listening socket - bind port number and local address to socket
	iResult = bind(listenSocket,(struct sockaddr*) &serverAddress,sizeof(serverAddress));


	// Check if socket is successfully binded to address and port from sockaddr_in structure
    if (iResult == SOCKET_ERROR)
    {
        printf("bind failed with error: %d\n", WSAGetLastError());
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

	unsigned long mode = 1; //non-blocking mode
	iResult = ioctlsocket(listenSocket, FIONBIO, &mode);

    // Set listenSocket in listening mode
    iResult = listen(listenSocket, SOMAXCONN);
    if (iResult == SOCKET_ERROR)
    {
        printf("listen failed with error: %d\n", WSAGetLastError());
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

	printf("Server socket is set to listening mode. Waiting for new connection requests.\n");



    do
    {
		// Struct for information about connected client
		sockaddr_in clientAddr;

		int clientAddrSize = sizeof(struct sockaddr_in);

        // Accept new connections from clients
        acceptedSocket = accept(listenSocket, (struct sockaddr *)&clientAddr, &clientAddrSize);

		// Check if accepted socket is valid
        if (acceptedSocket == INVALID_SOCKET)
        {
            printf("accept failed with error: %d\n", WSAGetLastError());
            closesocket(listenSocket);
            WSACleanup();
            return 1;
        }

		printf("\nNew client request accepted. Client address: %s : %d\n", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));

		do
		{
			// Receive data until the client shuts down the connection
			iResult = recv(acceptedSocket, dataBuffer, BUFFER_SIZE, 0);

			if (iResult != SOCKET_ERROR) {
				// Neblokirajuca operacija koja je uspesno izvrsena
				dataBuffer[iResult] = '\0';

				// Log message text
				printf("Client sent: %s.\n", dataBuffer);
				n=0;
				}
				else
				{
				if (WSAGetLastError() == WSAEWOULDBLOCK) {
					printf("Cekam.Broj pokusaja je:%d\n",n);
					n++;
					Sleep(1000);

				// U pitanju je blokirajuca operacija koja zbog rezima
				// soketa nece biti izvrsena
				}
				else {
					return 0;
				// Desila se neka druga greska prilikom poziva operacije
				}
				}
			if(n==15){
			break;
			}
			/*if (iResult > 0)	// Check if message is successfully received
			{


			}
			else if (iResult == 0)	// Check if shutdown command is received
			{
				// Connection was closed successfully
				printf("Connection with client closed.\n");
				closesocket(acceptedSocket);
			}
			else	// There was an error during recv
			{

				printf("recv failed with error: %d\n", WSAGetLastError());
				closesocket(acceptedSocket);
			}*/

		}while(iResult > 0);

        // Here is where server shutdown loguc could be placed

    } while (true);

    // Shutdown the connection since we're done
    iResult = shutdown(acceptedSocket, SD_BOTH);

	// Check if connection is succesfully shut down.
    if (iResult == SOCKET_ERROR)
    {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket(acceptedSocket);
        WSACleanup();
        return 1;
    }

    //Close listen and accepted sockets
    closesocket(listenSocket);
    closesocket(acceptedSocket);

	// Deinitialize WSA library
    WSACleanup();

    return 0;
}