/* 00001D8C */
u_long OpenEvent(u_long class, u_long spec, u_long mode, long (*func)())
{
      EvCB *block;
      int slot = get_free_EvCB_slot();
      if(slot == -1) return -1;

      block = *0x00000120 + slot*sizeof(EvCB);
      
      block->class = class;
      block->spec = spec;
      block->mode = mode;
      block->used = 0x1000;
      block->func = func;

      return (slot | 0xf1000000);
}