Techwiki:Ntoskrnl/DISPATCHER HEADER

  /*
   * NAME:           DISPATCHER_HEADER
   * DESCRIPTION:    Header for Dispatcher Objects
   * PORTABILITY:    Architecture Independent.
   * KERNEL VERSION: 5.2
   * DOCUMENTATION:  http://reactos.com/wiki/index.php/DISPATCHER_HEADER
   */

   union {
       struct {
           UCHAR         Type;            /* 000 */
           UCHAR         Absolute;        /* 001 */
           UCHAR         Size;            /* 002 */
           union {
               UCHAR     Inserted;        /* 003 */
               BOOLEAN   DebugActive;     /* 003 */
           };
       };
       volatile LONG     Lock;            /* 000 */
   };
   LONG                  SignalState;     /* 004 */
   LIST_ENTRY            WaitListHead;    /* 008 */