STPBK

Prolog  

Control Block Contents  
   STPBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

STPBK Prolog

 NAME       : SHARED TAPE DRIVE CONTROL BLOCK
 DESCRIPTION: SHARED-TAPE CONTROL BLOCK
 DSECT      : STPBK
 FUNCTION   : THIS CONTROL BLOCK MAPS SHARED TAPE DRIVE
              INFORMATION WHEN MULTIUSER IS SPECIFIED ON
              THE ATTACH CMD OR DEDICATE DIRECTORY STATEMENT.
 LOCATED BY : RDEVSTAP   SHARED TAPE BLOCK
 CREATED BY : HCPATDEV, HCPVRJDD
 DELETED BY : HCPDTDEV, HCPVRJLF, HCPVRJRL

STPBK Control Block Content

STPBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      STPBK          SHARED-TAPE CONTROL BLOCK
     ** FIELDS FOR ATTACH / DETACH
0000    0 Dbl-Word     8 STPALOCK (3)   Lock for field STPASIGN
0018   24 Signed       4 STPASIGN       Guest VDEV holding the Assign
001C   28 Bitstring   48 *              Reserved for future IBM use
004C   76 Bitstring    1 STPFLAG        Shared Tape miscellaneous bits
          1... ....      STPGSBIN       X'80' This guest survival block
                                        in use
004D   77 Bitstring    3 *              Reserved for future IBM use
0050   80 Signed       4 STPNGSBK       Next STPBK for V=R guest survival
0054   84 Signed       4 STPVDEV        USERS VDEV
          0000000B       STPDWSIZ       ((*-STPBK+7)/8) SIZE IN DWS FOR
                                        FREE/FRET

STPBK Storage Layout

          
*** STPBK - SHARED-TAPE CONTROL BLOCK
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       STPALOCK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  18 |         STPASIGN          |///////////////////////////|
*     +---------------------------+///////////////////////////|
*  20 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////+------+--------------------+
*  48 |///////////////////////////|:FLAG |////////////////////|
*     +---------------------------+------+--------------------+
*  50 |         STPNGSBK          |         STPVDEV           |
*     +---------------------------+---------------------------+
*  58
*
*** STPBK - SHARED-TAPE CONTROL BLOCK

STPBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
STPALOCK       0000
STPASIGN       0018
STPDWSIZ       0054 0000000B
STPFLAG        004C
STPGSBIN       004C 80
STPNGSBK       0050
STPVDEV        0054