    // ------------------------------- //
    // -------- Start of File -------- //
    // ------------------------------- //
    // ----------------------------------------------------------- //
    // C++ Source Code File Name: server.cpp
    // C++ Compiler Used: MSVC, BCC32, GCC, HPUX aCC, SOLARIS CC
    // Produced By: DataReel Software Development Team
    // File Creation Date: 10/30/2001
    // Date Last Modified: 06/17/2016
    // Copyright (c) 2001-2025 DataReel Software Development
    // ----------------------------------------------------------- //
    // ------------- Program Description and Details ------------- //
    // ----------------------------------------------------------- //
    /*
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
    USA

    Simple multicast server demo using the gxSocket class. This
    test program uses a UDP socket to join a IP multicast group
    and send/receive datagrams from a multicast group. Multicast
    addresses range from 224.0.0.0 to 239.255.255.255 with addresses
    from 224.0.0.0 to 224.0.0.255 reserved for multicast routing
    information. A multicast address identifies a set of receivers
    for multicast messages. A sender can send datagrams to any group
    without being a member of that group. Clients must be member of
    the multicast group in order to receive the multicast datagram
    message.

    NOTE: The Multicast examples programs will not compile using
    BCC32 5.5.1. The compiler complains about the IP_MULTICAST_TTL
    definition, the ip_mreq multicast address join structure, and the
    IP_ADD_MEMBERSHIP definition. These items are part of the Winsock
    library yet the BCC compiler will not recognize them.
    */
    // ----------------------------------------------------------- //
    #include "gxdlcode.h"

    #if defined (__USE_ANSI_CPP__) // Use the ANSI Standard C++ library
    #include <iostream>
    using namespace std; // Use unqualified names for Standard C++ library
    #else // Use the old iostream library by default
    #include <iostream.h>
    #endif // __USE_ANSI_CPP__

    #include <string.h>
    #include <stdlib.h>
    #include "gxsocket.h"

    #ifdef __BCC32__
    int main() { return 0; }
    #else
    int main(int argc, char **argv)
    {
      // Check arguments. Should be only one: the port number to bind to.
      if(argc != 3) {
        cerr << "Usage: " << argv[0] << " <Multicast IP> <Multicast Port>"
    	 << "\n" << flush;
        cerr << "Example: " << argv[0] << " 225.0.0.39 12345" << "\n" << flush;
        return 1;
      }

      char *multicast_ip = argv[1];
      unsigned short port = (unsigned short) atoi(argv[2]);
      int rv;

      cout << "Construcing datagram socket..." << "\n" << flush;
      gxSocket server(SOCK_DGRAM, SOCK_DGRAM, IPPROTO_UDP, port, multicast_ip);
      if(!server) {
        cout << server.SocketExceptionMessage() << "\n" << flush;
        return 1;
      }

      // Set the TTL of multicast packet to limit the number of hops a
      // multicast packet can traverse from the sender. As the TTL values
      // increase a router will expand the number of hops they will forward a
      // multicast packet:
      // 0:   Restricted to the same host
      // 1:   Restricted to the same subnet
      // 32:  Restricted to the same site
      // 64:  Restricted to the same region
      // 128: Restricted to the same continent
      // 255: Unrestricted
      unsigned char multicast_TTL = 1; // Restricted to the same subnet
      rv = server.SetSockOpt(IPPROTO_IP, IP_MULTICAST_TTL,
    			 (void *)&multicast_TTL, sizeof(multicast_TTL));
      if(rv < 0) {
        cout << "Could not change the default IP packet TTL" << "\n" << flush;
        cout <<  server.SocketExceptionMessage() << "\n" << flush;
        cout << "\n" << flush;
      }

      cout << "Sending multicast messages to group " << multicast_ip << "\n"
           << flush;
      cout << "Sending datagrams on port " << port << "\n" << flush;
      cout << "Press Ctrl-C to exit" << "\n" << flush;

      const char *message = "The quick brown fox jumps over the lazy dog \
    0123456789\n";

      while(1) {
        rv = server.SendTo((char *)message, strlen(message));
        if(rv < 0) {
          cout << server.SocketExceptionMessage() << "\n" << flush;
          break;
        }
    #ifdef __WIN32__
        Sleep(1000);
    #else
        sleep(1);
    #endif
      }

      cout << "Exiting..." << "\n" << flush;
      server.Close(); // Close the socket connection
      server.ReleaseSocketLibrary();
      return 0;
    }
    #endif // __BCC32__
    // ----------------------------------------------------------- //
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    // ------------------------------- //