Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

#### QUEBK

Prolog

Control Block Contents
QUEBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### QUEBK Prolog

     NAME       : HCPQUEBK
     DESCRIPTION: Queue Control Block
     DSECT      : QUEBK
     FUNCTION   : Control block used for inter-process communications via
                  queues.
     LOCATED BY : HCPCMSDQ  contains the static QUEBK for the ISFC Deliver queue.
                  HCPCMSRQ  contains the static QUEBK for the ISFC Resume queue.
                  LNKQUEBK  contains the QUEBK for a Link queue.
                  LNKIOQBK  contains the QUEBK for Link I/O.
                  HCPAAKIQ  contains the QUEBK for the CPAP mailbox
     CREATED BY : Operation of the ACTIVATE ISLINK command.
     DELETED BY : Operation of the DEACTIVE ISLINK command.
     SERIALIZED : LNKBK lock or ISFC Global Lock.

#### QUEBK Control Block Content

#### QUEBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      QUEBK          Queue Control Block
          QUEBK management.
    0000    0 Address      4 QUESTACK       Stack of LIFO work
    0004    4 Address      4 QUEREADR       Address of reader routine to call
    0008    8 Signed       4 * (2)          Reserve space for future routines
    0010   16 Dbl-Word     8 QUEPTRS (0)    Queue of FIFO work (head||tail)
    0010   16 Address      4 QUEHEAD        Address of first work element
                                            (FIFO)
    0014   20 Address      4 QUETAIL        Address of last work element
                                            (FIFO)
    0018   24 Signed       4 QUECHAIN       Offset to be used for chaining
                                            work
    001C   28 Signed       4 *              Reserved
    0020   32 Signed       4 QUEUWORD       Word reserved for use by queue
                                            owner
    0024   36 Signed       4 QUEUWRD2       Another word for use by owner
    0028   40 Signed       4 * (2)          Reserved
              00000006       QUESIZE        (*-QUEBK+7)/8 Size, in
                                            doublewords, of QUEBK

#### QUEBK Storage Layout

    *** QUEBK - Queue Control Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         QUESTACK          |         QUEREADR          |
    *     +---------------------------+---------------------------+
    *   8 |///////////////////////////////////////////////////////|
    *     +---------------------------+---------------------------+
    *  10 |         QUEHEAD           |         QUETAIL           |
    *     +---------------------------+---------------------------+
    *  18 |         QUECHAIN          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  20 |         QUEUWORD          |         QUEUWRD2          |
    *     +---------------------------+---------------------------+
    *  28 |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  30
    *
    *** QUEBK - Queue Control Block

#### QUEBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    QUECHAIN       0018
    QUEHEAD        0010
    QUEPTRS        0010
    QUEREADR       0004
    QUESIZE        0028 00000006
    QUESTACK       0000
    QUETAIL        0014
    QUEUWORD       0020
    QUEUWRD2       0024

This information is based on z/VM V6R1.0. Last updated on 18 Feb 2010 at 08:59:20 EDT.
Copyright IBM Corporation, 1990, 2008