NAME       : HCPRSSBK
 DESCRIPTION: RECORDING SYSTEM SERVICE BLOCK
 DSECT      : RSSBK
 FUNCTION   : MAPS OUT THE HEADER OF SYSTEM RECORDS ON THE
              RECORDING QUEUE.
 LOCATED BY : RTHQUE
              RSSNEXT CHAINED
 DELETED BY : HCPREC
 RELOCATION CONSIDERATIONS : None
 COMPATIBILITY AND MIGRATION CONCERNS : This control block gets checkpointed during SHUTDOWN and
              will be read back in during a WARM start.  Therefore, if
              the format of the block changes due to service being
              applied before the warm start, code should be in place to
              distinguish between the old and new format.  (See the
              note below describing the RSSVERS field.)

 RSSBK DSECT
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Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      RSSBK          RECORDING SYSTEM SERVICE BLOCK
0000    0 Address      4 RSSNEXT        Pointer to next RSSBK
0004    4 Signed       2 RSSUSCNT       SYSTEM RECORD USE COUNT
0006    6 Signed       2 RSSVN00M (0)   PLACE HOLDER (VERSION 00 INFO)
0006    6 Signed       2 *              RESERVED
0008    8 Bitstring    1 *              RESERVED
0009    9 Bitstring    1 RSSRID         SYSTEM RECORD ID
          00000001       RSSRACNT       X'01' RSSRACNT Accounting record
          00000002       RSSRIOER       X'02' RSSRIOER EREP (LOGREC)
                                        record
          00000003       RSSRSYMP       X'03' RSSRSYMP Sympton record
          00000004       RSSRCNFG       X'04' RSSRCNFG Configuration
                                        record
          000000FF       RSSRTAB        X'FF' RSSRTAB Recording table (if
                                        set block mapped by the RTHBK not
                                        the RSSBK, RSSRID must remain at
                                        the same offset as RTHRID)
000A   10 Signed       2 RSSFRESZ       RSSBK BLOCK SIZE IN DOUBLE WORDS
000C   12 Bitstring    1 RSSFLAG        FLAGS DEFINED FOR RECORDING
                                        SYSTEM SERVICES
          1... ....      RSSRINIT       X'80' RSSRINIT RECORD INITIALIZED
                                        TO RECORDING TABLE
          .1.. ....      RSSRINC        X'40' RSSRINC RECORD INCOMPLETE
          ..1. ....      RSSNOMON       X'20' RSSNOMON Record not
                                        monitored by Free Storage Limit
                                        Detection function NOTES : The
                                        following field is used to
                                        indicate when the RSSBK format
                                        has changed and what that change
                                        was due to. Any code defined here
                                        should be checked in HCPRECKP
                                        when old format RSSBKs are read
                                        from the checkpoint cylinders.
                                        The old format RSSBKs should then
                                        be updated appropriately to the
                                        new format. Code should also be
                                        added to HCPRIUCF and HCPRECRI to
                                        set the code for any RSSBKs that
                                        are being newly created AFTER the
                                        format change. A new code should
                                        only need to be defined here when
                                        a change to the RSSBK causes it
                                        to be incompatible with a
                                        previous format (as in the case
                                        of the RSSMSGN field being
                                        expanded from a halfword to a
                                        fullword). Due to compatibility,
                                        the displacement of RSSVERS
                                        should NEVER change. Previous
                                        versions of this control block
                                        had this field marked 'RESERVED'
                                        and the field was known to be
                                        zero. Therefore, previous
                                        versions were version X'00'. In
                                        addition, RSSFLAG should never be
                                        moved. This field is used without
                                        regard to the version of the
                                        RSSBK.
000D   13 Bitstring    1 RSSVERS        RSSBK VERSION INDICATOR
          00000000       RSSVN00        X'00' RSSVN00 For version 00,
                                        original format
          00000001       RSSVN01        X'01' RSSVN01 For version 01, the
                                        RSSMSGN field was expanded from a
                                        halfword to fullword
000E   14 Signed       2 RSSDCNT        LENGTH OF RSSDATA IN BYTES
0010   16 Signed       4 RSSMSGN        SYSTEM RECORD MESSAGE NUMBER
0014   20 Signed       4 *              RESERVED
0018   24 Character    1 RSSDATA (0)    START OF VARIABLE LENGTH SYSTEM
                                        RECORD DATA
          00000018       RSSBLEN        *-RSSBK RSSBK HEADER LENGTH IN
                                        BYTES
          00000003       RSSSIZE        (*-RSSBK+7)/8 RSSBK ENTRY IN
                                        DOUBLEWORDS
      The following mapping shows what the fields changed for the
      Version 01 RSSBK looked like in Version 00.  The following
      fields are used when updating Version 00 RSSBKs to Version
      01.
0006    6 Signed       2 RSSV00MN       RSSMSGN FIELD (Version 00 Format)
0010   16 Character    1 RSSV00DA (0)   RSSDATA FIELD (Version 00 Format)
          00000010       RSSV00HL       *-RSSBK Length of a Version 00
                                        Header

          
*** RSSBK - RECORDING SYSTEM SERVICE BLOCK
*
*     +---------------------------+-------------+-------------+
*   0 |         RSSNEXT           |  RSSUSCNT   |/////////////|
*     +------+------+-------------+------+------+-------------+
*   8 |//////|RSSRID|  RSSFRESZ   |:FLAG |:VERS |  RSSDCNT    |
*     +------+------+-------------+------+------+-------------+
*  10 |         RSSMSGN           |///////////////////////////|
*     +---------------------------+---------------------------+
*
*** RSSBK - RECORDING SYSTEM SERVICE BLOCK
          
*** Overlay for RSSVN00M in RSSBK
*
*                                               +-------------+
*   0 ...                                     6 |  RSSV00MN   |
*                                               +-------------+
*   8
*
*** Overlay for RSSVN00M in RSSBK
          
*** Overlay for RSSMSGN in RSSBK
*
*
*** Overlay for RSSMSGN in RSSBK

 
Symbol         Dspl Value
-------------- ---- -----
RSSBLEN        0018 00000018
RSSDATA        0018
RSSDCNT        000E
RSSFLAG        000C
RSSFRESZ       000A
RSSMSGN        0010
RSSNEXT        0000
RSSNOMON       000C 20
RSSRACNT       0009 00000001
RSSRCNFG       0009 00000004
RSSRID         0009
RSSRINC        000C 40
RSSRINIT       000C 80
RSSRIOER       0009 00000002
RSSRSYMP       0009 00000003
RSSRTAB        0009 000000FF
RSSSIZE        0018 00000003
RSSUSCNT       0004
RSSVERS        000D
RSSVN00        000D 00000000
RSSVN00M       0006
RSSVN01        000D 00000001
RSSV00DA       0010
RSSV00HL       0010 00000010
RSSV00MN       0006