char drivenamestr[32];
   strcpy(drivenamestr, "C:\\");
   DWORD sn=0, ignored1, ignored2;

   for (int drivename='C'; drivename<='Z'; drivename++) {
     drivenamestr[0]=drivename;
     if (GetVolumeInformation(drivenamestr, 0, 0, &sn, &ignored1, &ignored2,0, 0))
       break;
   };

   if (!sn) sn=0xE16E;
   sn^=0x35AF;
   srand(sn);

   volatile DWORD r32=0;
   for (int i=0; i<11; i++) {
     r32<<=15;
     r32|=rand();
   };

   DWORD generated_check=(rand()<<16) | rand();
   char gcheck[64];
   sprintf(gcheck, "%x", generated_check);