Listen&Eject: Ejecter

import std.stdio;
import std.socket;
import std.conv;
import std.process;

enum MAX_ATTEMPTS = 5;
enum TIMEOUT = 5;
enum MAX_WAIT_REBOOT_TIME = 300; //5 минут

void main(string[] argv) {
  if (argv.length < 2) { argv ~= "4455"; }
  ushort port = parse!ushort(argv[1]);
  auto addr = new InternetAddress(InternetAddress.ADDR_ANY, 4455);
  auto s = new UdpSocket();
  s.bind(addr);
  void[] buf = new void[1];
  writeln("Receiving datagrams on port ",port);

  s.setOption(SocketOptionLevel.SOCKET, SocketOption.RCVTIMEO, dur!"seconds"(TIMEOUT));
  auto attempts = MAX_ATTEMPTS;
  auto attemptsMultiplier = 1;
  while (true) {
    while (attempts > 0) {
      if (s.receiveFrom(buf) != Socket.ERROR) {
        write("\b",progressChar); stdout.flush;
        attempts = MAX_ATTEMPTS;
        attemptsMultiplier = 1;
      }
      else {
        attempts--;
        writeln(" [", currentDateTime, ": FAILED! ", to!string(attempts*TIMEOUT), "s. before eject CD]");
      }
    }
    writeln("[Ejecting CD-ROM]");
    system(`powershell $cds = (New-Object -ComObject "WMPlayer.OCX").cdromCollection; for($i=0;$i -lt $cds.Count;$i++) { $cds.Item($i).Eject() }`);
    attempts = attemptsMultiplier * (MAX_WAIT_REBOOT_TIME / TIMEOUT); //достаточное количество попыток для запуска компа
    attemptsMultiplier++;
  }
}

string currentDateTime() {
  import std.datetime;
  import std.algorithm;
  return findSplit(Clock.currTime().toString, ".")[0];
}

char progressChar() {
  static char[] chars = [ '-', '\\', '|', '/', ];
  static int index = 0;
  if (index == chars.length) index = 0;
  return chars[index++];
}