VFCBK | Back to Index page

| Prolog Control Block Contents VFCBK 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.

VFCBK Prolog | Top of page

     NAME       : HCPVFCBK
     DESCRIPTION: VIRTUAL FORMS BUFFER CONTROL BLOCK
     DSECT      : VFCBK
     FUNCTION   : CONTAINS THE FORMS CONTROL BUFFER DATA AND CONTROL
                  INFORMATION FOR A VIRTUAL SPOOLING DEVICE.
     LOCATED BY : VDSVFC    FIELD OF HCPVDSBK
     CREATED BY : HCPSCB - FOR PROCESSING THE LOADBUF COMMAND
     DELETED BY : HCPDTD - WHEN THE DEVICE IS DETACHED
     RELOCATION CONSIDERATIONS : This control block is relocated as part of a live
                  guest relocation (LGR).  The bits and fields that
                  need to be relocated are defined in the
                  corresponding LGRVFCBK COPY file.  Whenever changes
                  are made to this control block, consideration must
                  be given to any effects these changes will have on
                  a relocation.  If any new fields or bits are
                  defined, they may need to be relocated.  If
                  existing bits or fields are changed, corresponding
                  modifications may be required in the LGR version of
                  this control block.  Consider also the effects of
                  these changes on a relocation involving a back-level
                  release of CP.

VFCBK Control Block Content | Top of page

     VFCBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      VFCBK          VIRTUAL FORMS BUFFER CONTROL BLOCK
    0000    0 Character    4 VFCBNAME       FCB'S NAME
    0004    4 Bitstring    1 VFCBFLAG       STATUS FLAGS
              1... ....      VFCBEOF        X'80' VFCBEOF END OF FORMS PASSED
                                            ONCE
              .1.. ....      VFCBDIAG       X'40' VFCBDIAG USED IN 'READ
                                            BUFFER' SUPPORT
              ..1. ....      VFCBFCBV       X'20' VFCBFCBV FCB DATA VALID
              ...1 ....      VFCBREP        X'10' VFCBREP FCB DATA HAS JUST
                                            BEEN REPLACED
    0005    5 Bitstring    1 VFCBNUM        CHANNEL NUMBER OR SPACE COUNT
    0006    6 Signed       2 VFCBPOSN       CURRENT LINE NUMBER
    0008    8 Signed       4 VFCBWORK (0)   WORK WORD
    0008    8 Bitstring    1 VFCBPRED       THE LAST CCW ISSUED
    0009    9 Bitstring    1 * (3)          SPACE
    000C   12 Signed       4 VFCBRSV1       RESERVED FOR FUTURE IBM USE
    0010   16 Signed       2 VFCBLEN        LENGTH OF FCB DATA
    0012   18 Bitstring    1 VFCBINDX       FCB INDEX BYTE VALUE
    0013   19 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
    0014   20 Character  260 VFCBLOAD       FORMS CONTROL BUFFER DATA
    0118  280 Bitstring    1 * (2)          RESERVED FOR FUTURE IBM USE
    011A  282 Signed       2 VFCBPGCT       CURRENT PAGE COUNT
    011C  284 Character    4 VFCBIBUF       'SENSE INTERMEDIATE BUFFER' INFO
    0120  288 Dbl-Word     8 VFCBEND (0)    END OF VFC BUFFER BLOCK
              00000024       VFCBSIZE       (*-VFCBK)/8 BLOCK SIZE IN DBLWDS
    0014   20 Character  130 VFCBLOD1       FOR CLEARING: FCB 1ST HALF
    0096  150 Character  130 VFCBLOD2       FOR CLEARING: FCB 2ND HALF
    0014   20 Bitstring  256 VFCBNDAT       NORMAL FCB DATA
    0114  276 Character    1 VFCBENCH       END-OF-FCB FENCE
    0115  277 Bitstring    3 *              (UNUSED PORTION OF EXTENDED FCB)
    0014   20 Bitstring    1 VFCBFMT        FCB FORMAT INDICATOR
              0000007E       VFCBXTND       X'7E' VFCBXTND EXTENDED FCB
                                            FORMAT
    0015   21 Bitstring    1 VFCBFFLG       FCB FLAGS
              ...1 ....      VFCBXDUP       X'10' VFCBXDUP DUPLICATE COPY
                                            ENABLED
              1... ....      VFCBZERO       X'80' VFCBZERO BIT ZERO MUST BE 0
                                            BY DEFINITION
    0016   22 Bitstring    1 VFCBCOPY       COPY COUNT
    0017   23 Bitstring  256 VFCBXDAT       EXTENDED FCB: ACTUAL FCB DATA
    0117  279 Bitstring    1 VFCBEOFF       EXTENDED FCB END-OF-FORMS MARKER
              000000FE       VFCBXEOF       X'FE' VFCBXEOF EXTENDED FCB
                                            END-OF-FORMS CODE
    011C  284 Signed       2 VFCBFCBP       CURRENT FCB POINTER
    011E  286 Signed       2 VFCBCPGC       CURRENT PAGE COUNTER

VFCBK Storage Layout | Top of page

    *** VFCBK - VIRTUAL FORMS BUFFER CONTROL BLOCK
    *
    *     +---------------------------+------+------+-------------+
    *   0 |         VFCBNAME          |:BFLAG|:BNUM |  VFCBPOSN   |
    *     +------+--------------------+------+------+-------------+
    *   8 |:BPRED|////////////////////|         VFCBRSV1          |
    *     +------+------+------+------+---------------------------+
    *  10 |  VFCBLEN    |:BINDX|//////|                           |
    *     +-------------+------+------+                           |
    *  18 |                                                       |
    *     =                       VFCBLOAD                        =
    *     |                                                       |
    *     +-------------+-------------+---------------------------+
    * 118 |/////////////|  VFCBPGCT   |         VFCBIBUF          |
    *     +-------------+-------------+---------------------------+
    *
    *** VFCBK - VIRTUAL FORMS BUFFER CONTROL BLOCK

    *** Overlay for VFCBLOAD in VFCBK
    *
    *                                 +---------------------------+
    *     ...                      14 |                           |
    *     +---------------------------+                           |
    *  18 |                                                       |
    *     =                       VFCBLOD1                        =
    *     |                                         +-------------+
    *     |                                         |             |
    *     +-----------------------------------------+             |
    *  98 |                                                       |
    *     =                       VFCBLOD2                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    * 118
    *
    *** Overlay for VFCBLOAD in VFCBK

    *** Overlay for VFCBLOAD in VFCBK
    *
    *                                 +---------------------------+
    *     ...                      14 |                           |
    *     +---------------------------+                           |
    *  18 |                                                       |
    *     =                       VFCBNDAT                        =
    *     |                           +------+--------------------+
    * 110 |                           |:BENCH|////////////////////|
    *     +---------------------------+------+--------------------+
    * 118
    *
    *** Overlay for VFCBLOAD in VFCBK

    *** Overlay for VFCBLOAD in VFCBK
    *
    *                                 +------+------+------+------+
    *  10 ...                      14 |:BFMT |:BFFLG|:BCOPY|      |
    *     +---------------------------+------+------+------+      |
    *  18 |                                                       |
    *     =                       VFCBXDAT                        =
    *     |                                                +------+
    * 110 |                                                |:BEOFF|
    *     +------------------------------------------------+------+
    * 118
    *
    *** Overlay for VFCBLOAD in VFCBK

    *** Overlay for VFCBIBUF in VFCBK
    *
    *                                 +-------------+-------------+
    * 118 ...                     11C |  VFCBFCBP   |  VFCBCPGC   |
    *                                 +-------------+-------------+
    * 120
    *
    *** Overlay for VFCBIBUF in VFCBK

VFCBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    VFCBCOPY       0016
    VFCBCPGC       011E
    VFCBDIAG       0004 40
    VFCBENCH       0114
    VFCBEND        0120
    VFCBEOF        0004 80
    VFCBEOFF       0117
    VFCBFCBP       011C
    VFCBFCBV       0004 20
    VFCBFFLG       0015
    VFCBFLAG       0004
    VFCBFMT        0014
    VFCBIBUF       011C
    VFCBINDX       0012
    VFCBLEN        0010
    VFCBLOAD       0014
    VFCBLOD1       0014
    VFCBLOD2       0096
    VFCBNAME       0000
    VFCBNDAT       0014
    VFCBNUM        0005
    VFCBPGCT       011A
    VFCBPOSN       0006
    VFCBPRED       0008
    VFCBREP        0004 10
    VFCBRSV1       000C
    VFCBSIZE       0120 00000024
    VFCBWORK       0008
    VFCBXDAT       0017
    VFCBXDUP       0015 10
    VFCBXEOF       0117 000000FE
    VFCBXTND       0014 0000007E
    VFCBZERO       0015 80

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:31:33 EDT.
Copyright IBM Corporation, 1990, 2020