IHADECB Back to Index page
 
Prolog 
Control Block Contents 
   IHADECB DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This page documents intended Programming Interfaces that
allow the customer to write programs to obtain the services of z/VM.


  IHADECB Prolog Top of page
 
 NAME       : CMSCB
 DESCRIPTION: DATA EVENT CONTROL BLOCKS FOR
              BSAM, BISAM, BDAM, QTAM, BTAM.
 DSECT      : IHADECB
 FUNCTION   : IHADECB is the simulated data event control
              block used for CMS processing of OS macros and
              OS access methods. The IOBECBPT field in
              FCBSECT points to IHADECB.
 
 
  IHADECB Control Block Content Top of page
 

 IHADECB DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure IHADECB DATA EVENT CONTROL BLOCKS FOR 0000 0 Signed 4 DECSDECB - EVENT CONTROL BLOCK 0004 4 Signed 2 DECTYPE - TYPE OF I/O REQUEST 1... .... DECBRD X'80' DECBRD - READ SF ..1. .... DECBWR X'20' DECBWR - WRITE SF 0006 6 Signed 2 DECLNGTH - LENGTH OF KEY & DATA 0008 8 Address 4 DECDCBAD - V(DATA CONTROL BLOCK) 000C 12 Address 4 DECAREA - V(KEY & DATA, BUFFER) 0010 16 Address 4 DECIOBPT - V(IOB) BDAM EXTENSION 0014 20 Address 4 DECKYADR - V(KEY) 0018 24 Address 4 DECRECPT - V(BLOCK REFERENCE FIELD) SOME FREQUENTLY USED EQUATES 00000020 DDNAM FCBDSTYP - FILETYPE = DATA SET NAME ...1 .... BLK X'10' - RECFM=BLOCKED RECORDS ..1. .... BS X'20' - MACRF=BSAM ..1. .... DA X'20' - DSORG=DIRECT ACCESS 1... .... FXD X'80' - RECFM=FIXED LENGTH RECORDS 1... .... IS X'80' - DSORG=INDEXED SEQUENTIAL .... 1... LOC X'08' - MACRF=LOCATE MODE ...1 .... MOV X'10' - MACRF=MOVE MODE .1.. .... PS X'40' - DSORG=PHYSICAL SEQUENTIAL .... ..11 POU X'03' - DSORG=PARTITIONED UNMOVEABLE .... ..1. PO X'02' - DSORG=PARTIONED ORGANIZATION 1... .... PREVIOUS X'80' - OFLGS=PREVIOUS I/O OPERATION .1.. .... QS X'40' - MACRF=QSAM 11.. .... UND X'C0' - RECFM=UNDEFIN FORMAT RECORDS .1.. .... VAR X'40' - RECFM=VARIABLE LENGTH RECORDS ..1. .... ANSID X'20' - RECFM=VARIABLE LENGTH RECS (ANSI) .... 1... SPANNED X'08' - RECFM=SPANNED
 
 
  IHADECB Storage Layout Top of page
 
          
*** IHADECB - DATA EVENT CONTROL BLOCKS FOR
*
*     +---------------------------+-------------+-------------+
*   0 |         DECSDECB          |  DECTYPE    |  DECLNGTH   |
*     +---------------------------+-------------+-------------+
*   8 |         DECDCBAD          |         DECAREA           |
*     +---------------------------+---------------------------+
*  10 |         DECIOBPT          |         DECKYADR          |
*     +---------------------------+---------------------------+
*  18 |         DECRECPT          | 1C
*     +---------------------------+
*
*** IHADECB - DATA EVENT CONTROL BLOCKS FOR
 
 
  IHADECB Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
ANSID          0018 20
BLK            0018 10
BS             0018 20
DA             0018 20
DDNAM          0018 00000020
DECAREA        000C
DECBRD         0004 80
DECBWR         0004 20
DECDCBAD       0008
DECIOBPT       0010
DECKYADR       0014
DECLNGTH       0006
DECRECPT       0018
DECSDECB       0000
DECTYPE        0004
FXD            0018 80
IS             0018 80
LOC            0018 08
MOV            0018 10
PO             0018 02
POU            0018 03
PREVIOUS       0018 80
PS             0018 40
QS             0018 40
SPANNED        0018 08
UND            0018 C0
VAR            0018 40
 
This information is based on z/VM 7.1.0 Last updated on 22 Jun 2018 at 11:58:17 EDT.
Copyright IBM Corporation, 1990, 2018