WinSock_UDP_Broadcast

// Klient.cpp : Defines the entry point for the console application.
// 2018-04-13-udp-broadcast-kilent.cpp : Defines the entry point for the console application.
#include "stdafx.h"
#include <winsock.h>
#include <conio.h>
#include <locale.h>

#pragma comment(lib, "ws2_32")

int main() {
    setlocale(LC_ALL, "Polish");
    WSAData ws;
    if (WSAStartup(MAKEWORD(1, 0), &ws) != 0)
    {
        printf("Błąd inicjalizacji biblioteki WinSock.\n");
        _getch();
        return 0;
    }
    printf("Biblioteka WinSock utworzona pomyslnie.\n");
    SOCKET sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (sock == INVALID_SOCKET)
    {
        printf("Błąd utworzenia gniazda.\n");
        _getch();
        WSACleanup();
        return 0;
    }
    printf("Gniazdo utworzone pomyślnie.\n");
    sockaddr_in broadcast;
    broadcast.sin_addr.s_addr = INADDR_BROADCAST;
    broadcast.sin_port = htons(7602);
    broadcast.sin_family = AF_INET;
    int one = 1;
    setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char*)&one, sizeof(one));

    sockaddr_in address;
    int addrSize = sizeof(address);

    sockaddr_in serverUnicast;
    serverUnicast.sin_addr.s_addr = inet_addr("192.168.0.13");
    serverUnicast.sin_port = htons(7602);
    serverUnicast.sin_family = AF_INET;

    timeval time = { 0, 100000 };
    fd_set set;

    char recBuff[128];
    memset(recBuff, 0, sizeof(recBuff));

    char buff[128];
    memset(buff, 0, sizeof(buff));
    buff[0] = 0x30;
    buff[1] = 0x1D;
    strcat(buff, "Ulubiony język programowania?");
    buff[31] = 0x4;
    strcat(buff, "Java");
    buff[36] = 0x3;
    strcat(buff, "C++");
    buff[40] = 0x6;
    strcat(buff, "Python");
    buff[47] = 0x2;
    strcat(buff, "C#");
    sendto(sock, buff, sizeof(buff), 0, (SOCKADDR*)&broadcast, sizeof(broadcast));

    while (true)
    {
        FD_ZERO(&set);
        FD_SET(sock, &set);
        if (select(0, &set, 0, 0, &time) > 0)
        {
            if (FD_ISSET(sock, &set))
            {
                recvfrom(sock, recBuff, sizeof(recBuff), 0, (SOCKADDR*)&address, &addrSize);
            }
        }
        if (_kbhit())
        {
            char c = _getch();
            if (c == 27)
                break;
            if (c == 32)
            {
                memset(buff, 0, sizeof(buff));
                buff[0] = 0x30;
                buff[1] = 0x1D;
                strcat(buff, "Ulubiony język programowania?");
                buff[31] = 0x4;
                strcat(buff, "Java");
                buff[36] = 0x3;
                strcat(buff, "C++");
                buff[40] = 0x6;
                strcat(buff, "Python");
                buff[47] = 0x2;
                strcat(buff, "C#");
                sendto(sock, buff, sizeof(buff), 0, (SOCKADDR*)&broadcast, sizeof(broadcast));
            }
        }
    }
}