DTLBK Back to Index page
 
Prolog 
Control Block Contents 
   DTLBK 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.


  DTLBK Prolog Top of page
  
 NAME       : HCPDTLBK
 DESCRIPTION: DATALINK SOURCE
 DSECT      : DTLBK
 FUNCTION   : A VARIABLE LENGTH BUFFER CONTAINING THE
              DATALINK SOURCE FOR A TRACEID.  EACH BUFFER
              CONTAINS ONE DATALINK.  FOR MULTIPLE
              DATALINKS THE DTLBKS ARE CHAINED.
 LOCATED BY : TRCDTLBK
 CREATED BY : HCPTXF
              - HCPTXH
 DELETED BY : HCPTXD
              - HCPTXF
              - HCPTXP
 RELOCATION CONSIDERATIONS : None
 
 
  DTLBK Control Block Content Top of page
  




 DTLBK DSECT
Top of page


Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      DTLBK          DATALINK SOURCE
0000    0 Signed       4 DTLPTR         POINTER TO NEXT DTLBK
0004    4 Bitstring    1 DTLSIZE        SIZE (IN BYTES) OF THE DATALINK
0005    5 Bitstring    1 DTLIRSIZ       LENGTH OF DATALINK INTERNAL
                                        REPRESENTATION IN TRCBK
0006    6 Bitstring    1 DTLTYPE        Type of DTLBK
          1... ....      DTLDL          X'80' DTLDL DTLBK type is
                                        Datalink
          .1.. ....      DTLIF          X'40' DTLIF DTLBK type is IF
          ..1. ....      DTLTHEN        X'20' DTLTHEN DTLBK type is THEN
          ...1 ....      DTLELSE        X'10' DTLELSE DTLBK type is ELSE
          .... 1...      DTLENDIF       X'08' DTLENDIF DTLBK type is
                                        ENDIF
          .... .1..      DTLSNAP        X'04' DTLSNAP DTLBK type is SNAP
0007    7 Bitstring    1 *              Reserved For IBM Use
0008    8 Signed       2 DTLOFFST       Offset into TRCBK of the internal
                                        representation of this datalink.
000A   10 Bitstring    1 DTLSNCNT       SNAP count
000B   11 Bitstring    1 DTLSNREM       SNAPs remaining
000C   12 Signed       4 DTLDISP        DATALINK SOURCE
 
 
  DTLBK Storage Layout Top of page
  
          
*** DTLBK - DATALINK SOURCE
*
*     +---------------------------+------+------+------+------+
*   0 |          DTLPTR           |:SIZE |:IRSIZ|:TYPE |//////|
*     +-------------+------+------+------+------+------+------+
*   8 |  DTLOFFST   |:SNCNT|:SNREM|         DTLDISP           |
*     +-------------+------+------+---------------------------+
*  10
*
*** DTLBK - DATALINK SOURCE
 
 
  DTLBK Cross Reference Top of page
  
 
Symbol         Dspl Value
-------------- ---- -----
DTLDISP        000C
DTLDL          0006 80
DTLELSE        0006 10
DTLENDIF       0006 08
DTLIF          0006 40
DTLIRSIZ       0005
DTLOFFST       0008
DTLPTR         0000
DTLSIZE        0004
DTLSNAP        0006 04
DTLSNCNT       000A
DTLSNREM       000B
DTLTHEN        0006 20
DTLTYPE        0006
 
This information is based on z/VM 7.5.0 Last updated on 22 Jun 2026 at 11:13:07 EDT.
Copyright IBM Corporation, 1990, 2026