DNXBK Back to Index page
 
Prolog 
Control Block Contents 
   DNXBK DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.


  DNXBK Prolog Top of page
 
 NAME       : HCPDNXBK
 DESCRIPTION: Directory index block
 DSECT      : DNXBK
 FUNCTION   : The directory index block maps the header
              and entries for the various directory indices.
 LOCATED BY : DHDRUSER field of HCPDHDR
              DHDRUID  field of HCPDHDR
              DHDRGID  field of HCPDHDR
              DNXHDAD  field of HCPDHDR
 CREATED BY : HCPDIR
              HCPUDTBI
 DELETED BY : HCPUDSAT
              HCPUDSDS
              HCPUDSIN
 RELOCATION CONSIDERATIONS : None
 COMMENTS   : This DSECT references fields in
              HCPDUNDX, so any module using this DSECT must
              also COPY HCPDUNDX.
              This DSECT is used to map the various directory
              indices.  Each mapping consists of a header portion
              and a variable number of index entries.  A given
              DNXBK will only contain a single type of entry;
              that is, entry types are never mixed in a single
              DNXBK.  This DSECT is used to map both levels of
              the 2-level indices.
 
 
  DNXBK Control Block Content Top of page
 

 DNXBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure DNXBK Directory index block 0000 0 Bitstring 24 DNXHDR (0) Header portion of index block 0000 0 Signed 4 DNXHDAD DASD address of the next DNXBK for this index 0004 4 Signed 2 DNXHCNT Count of entries in this block 0006 6 Signed 2 * Reserved 0008 8 Character 16 DNXHLABL Label for this index 00000018 DNXHDRSZ *-DNXHDR Length of header portion in bytes 0018 24 Bitstring 1 DNXENTRY (0) First entry starts here ORG DNXENTRY Map an entry 0018 24 Bitstring 1 DNXGIDNT (0) GID index entry 0018 24 Bitstring 12 DNXGIPT1 (0) Part 1 of GID index entry 0018 24 Signed 4 DNXGID POSIX group ID (GID) 001C 28 Character 8 DNXGINAM POSIX group name 0024 36 Bitstring 10 DNXGIPT2 (0) Part 2 of GID index entry 0024 36 Signed 4 DNXGICNT Count of members in this group 0028 40 Signed 4 DNXGIDAD DASD address of first DGRPM block 002C 44 Signed 2 DNXGIDSP Displacement to first DGRPM block 00000016 DNXGINSZ *-DNXGIDNT GID entry size in bytes 0018 24 Bitstring 1 DNXUSRNT (0) Userid index entry 0018 24 Character 8 DNXUSBIG Largest userid in the page pointed to by DNXUSDAD 0020 32 Signed 4 DNXUSDAD DASD address of index page 0000000C DNXUSNSZ *-DNXUSRNT Userid entry size in bytes 0018 24 Bitstring 1 DNXUIDNT (0) UID index entry 0018 24 Signed 4 DNXUIBIG Largest UID in the page pointed to by DNXUIDAD 001C 28 Signed 4 DNXUIDAD DASD address of index page 00000008 DNXUINSZ *-DNXUIDNT UID entry size in bytes 0018 24 Character 8 * This field makes up the difference between the normal header above and the DUNDX page header (which is the same size as a DUNDX). 0020 32 Bitstring 1 DNXDUNDX (0) DUNDX page entry (see HCPDUNDX COPY for mapping).
 
 
  DNXBK Storage Layout Top of page
 
          
*** DNXBK - Directory index block
*
*     +---------------------------+-------------+-------------+
*   0 |         DNXHDAD           |  DNXHCNT    |/////////////|
*     +---------------------------+-------------+-------------+
*   8 |                       DNXHLABL                        |
*     |                                                       |
*     +---------------------------+---------------------------+
*  18 |          DNXGID           |        DNXGINAM-          |
*     +---------------------------+---------------------------+
*  20 |          -(01C)           |         DNXGICNT          |
*     +---------------------------+-------------+-------------+
*  28 |         DNXGIDAD          |  DNXGIDSP   | 2E
*     +---------------------------+-------------+
*
*** DNXBK - Directory index block
          
*** Overlay for DNXENTRY in DNXBK
*
*     +-------------------------------------------------------+
*  18 |                       DNXUSBIG                        |
*     +---------------------------+---------------------------+
*  20 |         DNXUSDAD          | 24
*     +---------------------------+
*
*** Overlay for DNXENTRY in DNXBK
          
*** Overlay for DNXENTRY in DNXBK
*
*     +---------------------------+---------------------------+
*  18 |         DNXUIBIG          |         DNXUIDAD          |
*     +---------------------------+---------------------------+
*  20
*
*** Overlay for DNXENTRY in DNXBK
          
*** Overlay for DNXENTRY in DNXBK
*
*     +-------------------------------------------------------+
*  18 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*
*** Overlay for DNXENTRY in DNXBK
 
 
  DNXBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
DNXDUNDX       0020
DNXENTRY       0018
DNXGICNT       0024
DNXGID         0018
DNXGIDAD       0028
DNXGIDNT       0018
DNXGIDSP       002C
DNXGINAM       001C
DNXGINSZ       002C 00000016
DNXGIPT1       0018
DNXGIPT2       0024
DNXHCNT        0004
DNXHDAD        0000
DNXHDR         0000
DNXHDRSZ       0008 00000018
DNXHLABL       0008
DNXUIBIG       0018
DNXUIDAD       001C
DNXUIDNT       0018
DNXUINSZ       001C 00000008
DNXUSBIG       0018
DNXUSDAD       0020
DNXUSNSZ       0020 0000000C
DNXUSRNT       0018
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:49:43 EDT.
Copyright IBM Corporation, 1990, 2022