*/
  public void make_current (GLXDrawable drawable) {
    RequestOutputStream o = display.out;
    synchronized (o) {
      o.begin_request (glx.major_opcode, 5, 4);
      o.write_int32 (drawable.id ());
      o.write_int32 (id);
      o.write_int32 (tag);
      ResponseInputStream i = display.in;
      synchronized (i) {
        i.read_reply (o);
        i.skip (8);
        tag = i.read_int32 ();
        i.skip (20);
      }
    }
  }