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

#### DMSCCB

Prolog

Control Block Contents
DMSCCB DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### DMSCCB Prolog

     Name       : DMSCCB
     Description: Command Control Block
     DSECT      : DMSCCB
     Function   : DMSCCB describes all fields of a VSE command
                  control block (CCB). This DSECT is used by
                  DMSXCP to map the CCB specified by a user for
                  an SVC 0 (EXCP). DMSCCB passes the address of
                  CCB to DMSXCP. DMSCCB is called by the DMSCCB
                  macro.

#### DMSCCB Control Block Content

#### DMSCCB DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      DMSCCB
              00000000       CCBST          * START CCB THIS IS THE
                                            DESCRIPTION OF THE CCB BLOCK
              00000000       CCBD           * COMMAND CONTROL BLOCK
    0000    0 Character   16 CCBLEN (0)     MAP OF THE DOS CCB
    0000    0 Bitstring    2 CCBCNT         RESIDUAL COUNT
    0002    2 Bitstring    4 CCBERMAP (0)   4 BYTES USED TO CHECK ERRORS
    0002    2 Bitstring    1 CCBCOM1        COMMUNICATIONS BYTE NO. 1
              1... ....      CCBWAIT        X'80' TRAFFIC BIT(SET AT CE)
              .1.. ....      CCBEOF         X'40' END-OF-FILE
              ..1. ....      CCBIOERR       X'20' UNRECOVERABLE I/O ERROR
              ...1 ....      CCBERROK       X'10' ACCEPT UNRECOVERABLE ERR
              .... 1...      CCBRDC         X'08' RETURN DATA CHECKS
              .... .1..      CCBPDE         X'04' POST AT DEVICE END
              .... ..1.      CCBDCV         X'02' RETURN DATA CHECK RD/CHK
              .... ...1      CCBUERR        X'01' USER ERROR ROUTINE
    0003    3 Bitstring    1 CCBCOM2        COMMUNICATIONS BYTE NO. 2
              1... ....      CCBDCCNT       X'80' DATA CHECK IN COUNT AREA
              .1.. ....      CCBTRKOV       X'40' TRACK OVERRUN
              ..1. ....      CCBEOC         X'20' END-OF-CYLINDER
              ...1 ....      CCBDC          X'10' DATA CHECK
              .... 1...      CCBNOREC       X'08' NO-RECORD-FOUND
              .... .1..      CCBRETRY       X'04' RETRY NO RECORD FOUND
              .... ..1.      CCBVER         X'02' VERIFY ERROR
              .... ...1      CCBCC          X'01' COMMAND CHAIN(RETRY)
    0004    4 Bitstring    1 CCBCSW1        CSW STATUS BIT NO. 1
              1... ....      CCBATTN        X'80' ATTENTION
              .1.. ....      CCBSTMOD       X'40' STATUS MODIFIER
              ..1. ....      CCBCUE         X'20' CONTROL UNIT END
              ...1 ....      CCBBUSY        X'10' BUSY
              .... 1...      CCBCE          X'08' CHANNEL END
              .... .1..      CCBDE          X'04' DEVICE END
              .... ..1.      CCBUC          X'02' UNIT CHECK
              .... ...1      CCBUE          X'01' UNIT EXCEPTION
    0005    5 Bitstring    1 CCBCSW2        CSW STATUS BIT NO. 2
              1... ....      CCBPCI         X'80' PROGRAM-CONTROLLED
                                            INTERRUPT
              .1.. ....      CCBILEN        X'40' INCORRECT LENGTH
              ..1. ....      CCBPROGM       X'20' PROGRAM CHECK
              ...1 ....      CCBPROT        X'10' PROTECTION CHECK
              .... 1...      CCBCHAND       X'08' CHANNEL DATA CHECK
              .... .1..      CCBCHANC       X'04' CHANNEL CONTROL CHECK
              .... ..1.      CCBICTRL       X'02' INTERFACE CONTROL CHECK
              .... ...1      CCBCHAIN       X'01' CHAINING CHECK
    0006    6 Bitstring    2 CCBSYMU (0)    SYMBOLIC UNIT(SYSUN)
    0006    6 Bitstring    1 CCBSUCLS       U - LUB CLASS
    0007    7 Bitstring    1 CCBSUNUM       N - LUB NUMBER WITHIN CLASS
    0008    8 Bitstring    1 CCBLIOBS       RESERVED FOR LIOBS
    0009    9 Bitstring    3 CCBCCW         PT TO START OF CHANNEL PROGRAM
    000C   12 Bitstring    1 CCBCOM3        COMMUNICATION BYTE NO. 3
              .1.. ....      CCBAPEND       X'40' APPENDAGE EXIT AT INTERRUPT
              .... ...1      CCBCCWF1       X'01' Format-1 CCWs present
    000D   13 Bitstring    3 CCBCSW         PT TO CSW OR PT APPENDAGE RTN
    0010   16 Address      4 CCBLDATB       ADDRESS OF LAST DATA BLOCK
    0014   20 Address      4 CCBLCCWB       ADDRESS OF LAST CCW BLOCK
    0018   24 Signed       4 *              AVAILABLE
    001C   28 Bitstring    1 CCBUFLGS       I/O MANAGER CCB FLAGS
              1... ....      CCBUEAIC       X'80' ERROR ANALYSIS IN CONTROL
              .1.. ....      CCBUEAC        X'40' ERROR ANALYSIS COMPLETE
              ..1. ....      CCBURDCW       X'20' READ CCW ACTIVE
              ...1 ....      CCBRPS         X'10' RPS CHAN PGM CANDIDATE
    001D   29 Bitstring    3 CCBFSCCW       SAVE AREA FOR FIRST CCW ADDR
    0020   32 Signed       4 CCBRDCCW       ADDRESS OF FIRST READ CCW
    0024   36 Signed       4 CCBWTCCW       ADDRESS OF FIRST WRITE CCW
    0028   40 Signed       4 CCBLWCCW       ADDRESS OF THE LAST WRITE CCW
    002C   44 Signed       4 * (3)          AVAILABLE THIS CHAIN FIELD MUST
                                            HAVE SAME DISPLACEMENT AS
                                            FCBCHAIN IN FCDB AND BKPFSTBK IN
                                            BKPHD
    0038   56 Address      4 CCBNCCB        ADDRESS OF NEXT CCB BLOCK
    003C   60 Signed       4 *              AVAILABLE

#### DMSCCB Storage Layout

    *** DMSCCB - Control Block in DMSCCB
    *
    *     +-------------+------+------+------+------+------+------+
    *   0 |   CCBCNT    |:COM1 |:COM2 |:CSW1 |:CSW2 |:SUCLS|:SUNUM|
    *     +------+------+------+------+------+------+------+------+
    *   8 |:LIOBS|      CCBCCW        |:COM3 |      CCBCSW        |
    *     +------+--------------------+------+--------------------+
    *  10 |         CCBLDATB          |         CCBLCCWB          |
    *     +---------------------------+------+--------------------+
    *  18 |///////////////////////////|:UFLGS|     CCBFSCCW       |
    *     +---------------------------+------+--------------------+
    *  20 |         CCBRDCCW          |         CCBWTCCW          |
    *     +---------------------------+---------------------------+
    *  28 |         CCBLWCCW          |///////////////////////////|
    *     +---------------------------+///////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     +---------------------------+---------------------------+
    *  38 |         CCBNCCB           |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  40
    *
    *** DMSCCB - Control Block in DMSCCB

#### DMSCCB Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    CCBAPEND       000C 40
    CCBATTN        0004 80
    CCBBUSY        0004 10
    CCBCC          0003 01
    CCBCCW         0009
    CCBCCWF1       000C 01
    CCBCE          0004 08
    CCBCHAIN       0005 01
    CCBCHANC       0005 04
    CCBCHAND       0005 08
    CCBCNT         0000
    CCBCOM1        0002
    CCBCOM2        0003
    CCBCOM3        000C
    CCBCSW         000D
    CCBCSW1        0004
    CCBCSW2        0005
    CCBCUE         0004 20
    CCBD           0000 00000000
    CCBDC          0003 10
    CCBDCCNT       0003 80
    CCBDCV         0002 02
    CCBDE          0004 04
    CCBEOC         0003 20
    CCBEOF         0002 40
    CCBERMAP       0002
    CCBERROK       0002 10
    CCBFSCCW       001D
    CCBICTRL       0005 02
    CCBILEN        0005 40
    CCBIOERR       0002 20
    CCBLCCWB       0014
    CCBLDATB       0010
    CCBLEN         0000
    CCBLIOBS       0008
    CCBLWCCW       0028
    CCBNCCB        0038
    CCBNOREC       0003 08
    CCBPCI         0005 80
    CCBPDE         0002 04
    CCBPROGM       0005 20
    CCBPROT        0005 10
    CCBRDC         0002 08
    CCBRDCCW       0020
    CCBRETRY       0003 04
    CCBRPS         001C 10
    CCBST          0000 00000000
    CCBSTMOD       0004 40
    CCBSUCLS       0006
    CCBSUNUM       0007
    CCBSYMU        0006
    CCBTRKOV       0003 40
    CCBUC          0004 02
    CCBUE          0004 01
    CCBUEAC        001C 40
    CCBUEAIC       001C 80
    CCBUERR        0002 01
    CCBUFLGS       001C
    CCBURDCW       001C 20
    CCBVER         0003 02
    CCBWAIT        0002 80
    CCBWTCCW       0024

This information is based on z/VM V4R4.0.
Last updated on 28 Jul 2003 at 08:14:21 EDT.
Copyright IBM Corporation, 1990, 2003