TPCBK - 64-bit CP - V4R4.0

Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

#### TPCBK

Prolog

Control Block Contents
TPCBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### TPCBK Prolog

     NAME       : HCPTPCBK
     DESCRIPTION: TAPE PATHING CONTROL BLOCK
     DSECT      : TPCBK
     FUNCTION   : CONTAINS TAPE PATHING INFORMATION
     LOCATED BY : VDEVDYPT IN VIRTUAL DEVICE BLOCK
     CREATED BY : HCPVDSAT (DURING ATTACH OR DEDICATE PROC)
     DELETED BY : HCPDTDEV (DURING DETACH COMMAND PROCESSING)
     SERIALIZED : BEING ACCESSED FOR A UNIQUE TASK

#### TPCBK Control Block Content

#### TPCBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      TPCBK          TAPE PATHING CONTROL BLOCK
    0000    0 Bitstring   12 TPCBLOCK (8)   EIGHT ENTRIES OF PATHING
                                            INFORMATION
              0000000C       TPCSIZE        (*-TPCBK+7)/8 TPCBK SIZE IN
                                            DOUBLE WORDS
    0000    0 Bitstring   12 TPCENTRY (0)   ONE ENTRY OF TAPE PATHING BLOCK
    0000    0 Bitstring   11 TPCGROUP       TAPE PATH GROUP ID
    000B   11 Bitstring    1 TPCFLAGS       TAPE PATHING FLAGS
              1... ....      TPCFGRP        X'80' PATH IS GROUPED
              0000000C       TPCNXTEN       *-TPCENTRY

#### TPCBK Storage Layout

    *** TPCBK - TAPE PATHING CONTROL BLOCK
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       TPCBLOCK                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  60
    *
    *** TPCBK - TAPE PATHING CONTROL BLOCK

    *** Overlay for TPCBLOCK in TPCBK
    *
    *     +-------------------------------------------------------+
    *   0 |                       TPCGROUP                        |
    *     |                    +------+---------------------------+
    *   8 |                    |:FLAGS| C
    *     +--------------------+------+
    *
    *** Overlay for TPCBLOCK in TPCBK

#### TPCBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    TPCBLOCK       0000
    TPCENTRY       0000
    TPCFGRP        000B 80
    TPCFLAGS       000B
    TPCGROUP       0000
    TPCNXTEN       000B 0000000C
    TPCSIZE        0000 0000000C

This information is based on z/VM V4R4.0. Last updated on 30 Jul 2003 at 13:23:05 EDT.
Copyright IBM Corporation, 1990, 2003