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

#### HDRBK

Prolog

Control Block Contents
HDRBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### HDRBK Prolog

     NAME       : DMSHDRBK
     DESCRIPTION: Free storage element header
     DSECT      : HDRBK
     FUNCTION   : Mapping macro which maps unallocated
                  pieces of storage within a page.

#### HDRBK Control Block Content

#### HDRBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      HDRBK          Free storage element header
    0000    0 Signed       4 HDRFORWD       Pointer to next piece of free
                                            storage
    0004    4 Signed       4 HDRLEN         Size of this piece of free
                                            storage

#### HDRBK Storage Layout

    *** HDRBK - Free storage element header
    *
    *     +---------------------------+---------------------------+
    *   0 |         HDRFORWD          |          HDRLEN           |
    *     +---------------------------+---------------------------+
    *   8
    *
    *** HDRBK - Free storage element header

#### HDRBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    HDRFORWD       0000
    HDRLEN         0004

This information is based on z/VM V6R1.0.
Last updated on 23 Oct 2009 at 10:58:17 EDT.
Copyright IBM Corporation, 1990, 2008