PeteTCPClient

#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")

#pragma pack(1)

#define SERVER_IP_ADDRESS "127.0.0.1"
#define SERVER_PORT 27016
#define BUFFER_SIZE 256


struct studentInfo{
    char ime [15];
    char prezime [20];
    short poeni;
};

// TCP client that use non-blocking sockets
int main()
{
    // Socket used to communicate with server
    SOCKET connectSocket = INVALID_SOCKET;

    // Variable used to store function return value
    int iResult;

    // Buffer we will use to store message
    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;
    }

    // create a socket
    connectSocket = socket(AF_INET,
                           SOCK_STREAM,
                           IPPROTO_TCP);

    if (connectSocket == INVALID_SOCKET)
    {
        printf("socket failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    // Create and initialize address structure
    sockaddr_in serverAddress;
    serverAddress.sin_family = AF_INET;                             // IPv4 protocol
    serverAddress.sin_addr.s_addr = inet_addr(SERVER_IP_ADDRESS);   // ip address of server
    serverAddress.sin_port = htons(SERVER_PORT);                    // server port

    // Connect to server specified in serverAddress and socket connectSocket
    iResult = connect(connectSocket, (SOCKADDR*)&serverAddress, sizeof(serverAddress));
    if (iResult == SOCKET_ERROR)
    {
        printf("Unable to connect to server.\n");
        closesocket(connectSocket);
        WSACleanup();
        return 1;
    }

        //promenljiva tipa studentInfo cija ce se polja popunuti i cela struktira poslati u okviru jedne poruke
        studentInfo student;
    short poeni;

    while(true)
    {
        // Unos potrebnih podataka koji ce se poslati serveru
        printf("Unesite ime studenta: ");
        gets_s(student.ime, 15);

        printf("Unesite prezime studenta: ");
        gets_s(student.prezime, 20);

        printf("Unesite osvojene poene na testu: ");
        scanf("%d", &poeni);
        student.poeni=htons(poeni);  //obavezna funkcija htons() jer cemo slati podatak tipa short
        getchar();    //pokupiti enter karakter iz bafera tastature


        // Slanje pripremljene poruke zapisane unutar strukture studentInfo
        //prosledjujemo adresu promenljive student u memoriji, jer se na toj adresi nalaze podaci koje saljemo
        //kao i velicinu te strukture (jer je to duzina poruke u bajtima)
        iResult = send( connectSocket, (char*) &student, (int)sizeof(studentInfo), 0 );

        // Check result of send function
        if (iResult == SOCKET_ERROR)
        {
            printf("send failed with error: %d\n", WSAGetLastError());
            closesocket(connectSocket);
            WSACleanup();
            return 1;
        }

        printf("Message successfully sent. Total bytes: %ld\n", iResult);

        printf("\nPress 'x' to exit or any other key to continue: ");
        if(getch() == 'x')
            break;
    }

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

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

    Sleep(1000);

    // Close connected socket
    closesocket(connectSocket);

    // Deinitialize WSA library
    WSACleanup();

    return 0;
}