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Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM. |
DGDBK
Control Block Contents
DGDBK DSECT
Cross Reference (Contains links to field and bit definitions)
DGDBK Prolog
Name : HCPDGDBK
Description: Directory generic data block
DSECT : DGDBK
Function : The directory generic data block maps a block
written by the generic write routine in HCPDIR.
Located by : DGRPNDAD/DGRPNDSP fields of HCPDGRPM
DVMDWDAD/DVMDWDSP fields of HCPDVMD
DVMDUDAD/DVMDUDSP fields of HCPDVMD
DVMDRDAD/DVMDRDSP fields of HCPDVMD
DVMDSDAD/DVMDSDSP fields of HCPDVMD
DNXGIDAD/DNXGIDSP fields of HCPDNXBK
Created by : HCPDIR
Deleted by : None
Comments : A directory generic data block can be
considered to consist of 2 overlapping entities.
The "generic block" is the entire block and includes
the generic header and a variable length "data
block". The data block is identified by the DGDID
field and is usually mapped by its own DSECT.
These blocks are written to the directory DASD
by HCPDIR's generic write routine, and they are
read and handled by the directory generic read
routine, HCPUDPRD.
DGDBK Control Block Content
DGDBK DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure DGDBK Directory generic data block 0000 0 Signed 4 DGDLEN Total length of the generic block (generic header + data block) 0004 4 Bitstring 1 * (3) Reserved for IBM use 0007 7 Bitstring 1 DGDID ID number that identifies the specific type of the data block 00000001 DGDIDGRP 1 ID number for DGRPM 00000002 DGDIDDGS 2 ID number for DGSBK 00000003 DGDIDSGR 3 ID number for DSGR 00000000 * 00000008 DGDHDRSZ *-DGDBK Generic header size, in bytes 0008 8 Bitstring 1 DGDDBLOK (0) The data block starts here
DGDBK Storage Layout
*** DGDBK - Directory generic data block
*
* +---------------------------+--------------------+------+
* 0 | DGDLEN |////////////////////|DGDID |
* +---------------------------+--------------------+------+
*
*** DGDBK - Directory generic data block
DGDBK Cross Reference
Symbol Dspl Value -------------- ---- ----- * 0007 00000000 DGDDBLOK 0008 DGDHDRSZ 0007 00000008 DGDID 0007 DGDIDDGS 0007 00000002 DGDIDGRP 0007 00000001 DGDIDSGR 0007 00000003 DGDLEN 0000
Last updated on 5 Jun 2001 at 13:19:36 EDT.
Copyright IBM Corporation, 1990, 2001