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

#### CCTBK

Prolog

Control Block Contents
CCTBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### CCTBK Prolog

     NAME       : HCPCCTBK
     DESCRIPTION: Communications Control Table
     DSECT      : CCTBK
     FUNCTION   : THIS CONTROL BLOCK DEFINES THE COMMUNICATION CONTROL
                  TABLE FOR AN IUCV USER.
     LOCATED BY : IUCVCCT FIELD OF HCPIUCVB
     CREATED BY : HCPIUJDB - IUCV DECLARE BUFFER FUNCTION
     DELETED BY : HCPIUERB - IUCV RETRIEVE BUFFER FUNCTION

#### CCTBK Control Block Content

#### CCTBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      CCTBK          Communications Control Table
    0000    0 Signed       2 CCTMXPID       CURRENT MAX PATH ID FOR THIS CCT
    0002    2 Bitstring    1 *              Reserved
    0003    3 Bitstring    1 CCTFLAG2       IUCV INTERRUPTS PENDING
              1... ....      CCTPNDSN       X'80' IUCV NON-PRIORITY MSGS
                                            PENDING
              .1.. ....      CCTPNDSP       X'40' IUCV PRIORITY MESSAGES
                                            PENDING
              ..1. ....      CCTPNDRN       X'20' IUCV NON-PRIORITY REPLIES
                                            PENDING
              ...1 ....      CCTPNDRP       X'10' IUCV PRIORITY REPLIES
                                            PENDING
              .... 1...      CCTPNDCT       X'08' IUCV CONTROL INTERRUPT
                                            PENDING
    0004    4 Address      4 CCTIUCV        POINTER TO THE USER'S IUCVBK
    0008    8 Address      4 CCTSNDHD       SEND QUEUE HEAD
    000C   12 Address      4 CCTSNDTL       SEND QUEUE TAIL
    0010   16 Address      4 CCTSNDPR       SEND PRIORITY QUEUE TAIL
    0014   20 Address      4 CCTRCVHD       RECEIVE QUEUE HEAD
    0018   24 Address      4 CCTRCVTL       RECEIVE QUEUE TAIL
    001C   28 Address      4 CCTRPYHD       REPLY QUEUE HEAD
    0020   32 Address      4 CCTRPYTL       REPLY QUEUE TAIL
    0024   36 Address      4 CCTRPYPR       REPLY PRIORITY QUEUE TAIL
    0028   40 Signed       4 CCTMSGCT       TOTAL MSGS SENT ON ALL PATHS
    002C   44 Bitstring    1 *              Reserved
    002D   45 Bitstring    1 CCTCPSYS       CP SYSTEM SERVICE CODE
          NOTES      : SYSTEM SERVICE CODES MUST MATCH WITH THE SAME VALUES
                LISTED IN CSSTABLE ENTRIES IN HCPIUG AND VALUES USED
                TO INITIALIZE IPCPSYS IN THE IUCV MACRO
              .... .111      CCTSSCCS       X'07' CODE FOR *CCS SYSTEM
                                            SERVICE
    002E   46 Bitstring    1 CCTSTAT        STATUS
              1... ....      CCTRTVBF       X'80' RETRIEVE BUFFER IN PROGRESS
              .1.. ....      CCTSYNC        X'40' ABLE TO PROCESS SYNC SENDS
              ..1. ....      CCTCPINT       X'20' CP server interrupt in
                                            progress
              ...1 ....      CCTSTKED       X'10' IUCV INTERRUPT IS STACKED
    002F   47 Bitstring    1 *              RESERVED
    0030   48 Signed       4 *              Reserved for future use
    0034   52 Signed       4 *              Reserved for future use
           THE CCTDESCT FIELD HAS BEEN ADDED TO KEEP TRACK OF THE
           NUMBER OF MESSAGE PENDING INTERRUPTS THAT NEED TO BE
           REFLECTED.  THIS COUNT IS INCREMENTED WHEN A MESSAGE IS
           PLACED ON THE SEND QUEUE AND IS DECREMENTED WHEN EITHER THE
           INTERRUPT IS REFLECTED OR THE MESSAGE IS DESCRIBED.
    0038   56 Signed       4 CCTDESCT       SEND QUEUE MSGS TO BE DESCRIBED
           ADD A RESERVED FIELD TO FORCE A DOUBLEWORD BOUNDARY FOR
           THE CCTPDSEG FIELD SO BLOCKDEF WILL WORK PROPERLY.
    003C   60 Signed       4 *              RESERVED
           START OF PATH DESCRIPTION SEGMENT POINTERS (DWD ALIGNED)
    0040   64 Dbl-Word     8 * (0)          ALIGNMENT
    0040   64 Signed       4 CCTPDSEG (0)   N (1<=N<=256) PDSEG
                                            POINTERS
              .1.. ..11      CCTPDSLO       CCTPDSEG+3 BYTE FOR INVALID PDSEG
                                            TEST
              .... ...1      CCTSINV        X'01' PDSEG INVALID BIT
              00000008       CCTSIZE        (*-CCTBK+7)/8 CCTBK SIZE IN
                                            DOUBLEWORDS

#### CCTBK Storage Layout

    *** CCTBK - Communications Control Table
    *
    *     +-------------+------+------+---------------------------+
    *   0 |  CCTMXPID   |//////|:FLAG2|         CCTIUCV           |
    *     +-------------+------+------+---------------------------+
    *   8 |         CCTSNDHD          |         CCTSNDTL          |
    *     +---------------------------+---------------------------+
    *  10 |         CCTSNDPR          |         CCTRCVHD          |
    *     +---------------------------+---------------------------+
    *  18 |         CCTRCVTL          |         CCTRPYHD          |
    *     +---------------------------+---------------------------+
    *  20 |         CCTRPYTL          |         CCTRPYPR          |
    *     +---------------------------+------+------+------+------+
    *  28 |         CCTMSGCT          |//////|:CPSYS|:STAT |//////|
    *     +---------------------------+------+------+------+------+
    *  30 |///////////////////////////|///////////////////////////|
    *     +---------------------------+---------------------------+
    *  38 |         CCTDESCT          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *
    *** CCTBK - Communications Control Table

#### CCTBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    CCTCPINT       002E 20
    CCTCPSYS       002D
    CCTDESCT       0038
    CCTFLAG2       0003
    CCTIUCV        0004
    CCTMSGCT       0028
    CCTMXPID       0000
    CCTPDSEG       0040
    CCTPDSLO       0040 43
    CCTPNDCT       0003 08
    CCTPNDRN       0003 20
    CCTPNDRP       0003 10
    CCTPNDSN       0003 80
    CCTPNDSP       0003 40
    CCTRCVHD       0014
    CCTRCVTL       0018
    CCTRPYHD       001C
    CCTRPYPR       0024
    CCTRPYTL       0020
    CCTRTVBF       002E 80
    CCTSINV        0040 01
    CCTSIZE        0040 00000008
    CCTSNDHD       0008
    CCTSNDPR       0010
    CCTSNDTL       000C
    CCTSSCCS       002D 07
    CCTSTAT        002E
    CCTSTKED       002E 10
    CCTSYNC        002E 40

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 16:43:20 EDT.
Copyright IBM Corporation, 1990, 2005