NAME       : HCPSNTBK
 DESCRIPTION: System Name Table Block
 DSECT      : SNTBK
 FUNCTION   : This block is used to keep track of a system data
              file that is brought into the system.
 LOCATED BY : The pointer to this chain of blocks is located in
              HCPNSU, using NSUNSYAN for NSSs, NSUNSGAN for
              DCSSs, NSUIMGAN for images, and NSUNLSAN for
              NLS files.
              - In HCPSHRBK, pointer SHRSNTPT will point to the
              associated HCPSNTBK.
              Pointer SHRLSSA will point to the segment space
              through which the shared segment was loaded.
              - In HCPPGMBK, using the PGMVM pointer will point to the
              associated HCPSNTBK.
              - SNTFWDPT will point to the next HCPSNTBK in the chain.
              - The end of chain is located when the SNTFWDPT equals
              the address of NSUNSYAN, NSUNSGAN OR NSUIMGAN.
              - In HCPIMGBK, IMGSNTBK will point to the
              associated HCPSNTBK.
 CREATED BY : HCPNSL when loading the NSS or DCSS for the first
              time.
              - HCPNSD will build this block for the duration of the
              processing of the DEFSEG and DEFSYS commands.
              - HCPNSS will build this block for the duration of the
              processing of the SAVESEG and SAVESYS commands.
              - HCPNSI will build this block for the duration
              of processing of the diagnose X'74' instruction
              to save or load an image, and the diagnose
              X'CC' instruction to create an NLS message
              repository.
              - HCPNSR will build this block when opening an
              image library or NLS message repository file.
 DELETED BY : HCPNSP will delete this block when the count fields
              of an NSS or DCSS go to zero. The fields are
              SNTUSRSH and SNTUSREX.
              - HCPNSD will delete this block after processing
              the DEFSEG or DEFSYS command.
              - HCPNSS will delete this block after processing the
              SAVESEG or SAVESYS command.
              - HCPNSI will delete this block after processing
              diagnose X'74' to save or load an image, or
              diagnose X'CC' to create an NLS message
              repository.
              - HCPNSR will delete this block when closing the
              image library or NLS message repository.
 RELOCATION CONSIDERATIONS : None
 COMMENTS   :
              - The size of this block is 4K, a page of storage.
              - *****NOTE***** This control block maps the
              descriptor page for certain system data files.
              Extreme care must be exercised when updating this
              block, to avoid causing files created prior to
              the update to break. Changes must be made in an
              upward-compatible way
              - Two formats (31-bit and 64-bit) of the SNTBK are
              defined here.  The 31-bit format is an old format
              that exists only on spool for a below-2G NSS,
              DCSS, NLS, or IMG. When a 31-bit format SNTBK is
              read-in it is converted to 64-bit format by
              HCPNSBTG. Similarly, when a below-2G file is
              written out, HCPNSBGT converts it from 64-bit
              format to 31-bit format before the write is done.
              All in-storage accesses of the SNTBK block by CP
              are done using the 64-bit format. When converting
              between the 31-bit and 64-bit formats, HCPNSB
              uses only a subset of the original 31-bit field
              names (specifically those defined at the
              higher-level encapsulating several smaller
              fields). As a result, some of the 31-bit field
              names are no longer referenced by CP and have
              been "removed" or "reserved" as indicated in the
              list below.  See PITS 2U00987 for more details.
              Reserved --> points to labels that have been
              removed, but their corresponding DS statements
              are still used as "Reserved" declarations to
              preserve SNTBK offsets.
              Removed --> points to labels and EQUates that
              have been completely removed, for doing so
              does not disrupt SNTBK offsets.
              31-bit format      64-bit format
              SNTMEMSR(3-word)   SNTMSRG(5-word)
              SNTSTPAG(32-bit)   SNTSTPGG(64-bit)_
              SNTENPAG(32-bit)   SNTENPGG(64-bit)
  eserved --> SNTLODCT(32-bit)   SNTLODCG(32-bit)
              SNTCPNTL(32-bit)   SNTCPNTG(32-bit)
              SNTNOTAM(32-bit)   SNTNOTAG(32-bit)
              SNTMENVF(1-byte)   SNTMENVG(1-byte)
              SNTRANGE(2-word)   SNTRANGG(4-word)
              SNTPRMAX(=128)     SNTPRMXG(=64)
              SNTRANS (32-bit)   SNTRANSG(64-bit)
              Removed --> SNTRSNOF(3-byte)   SNTRSNOG(7-byte)
              Removed --> SNTRNGFG(1-byte)   SNTRGFGG(1-byte)
              SNTRANE (32-bit)   SNTRANEG(64-bit)
              SNTMEMDA(4-word)   SNTMEMDG(6-word)
              SNTMSSNM(2-word)   SNTMSSNG(2-word)
              SNTMEMST(32-bit)   SNTMEMSG(64-bit)
              Removed --> SNTMEMSP(3-byte)   SNTMSPG (7-byte)
              Removed --> SNTMSTAT(1-byte)   SNTMSTAG(1-byte)
              SNTMSSA (32-bit)   SNTMSSAG(32-bit)

 SNTBK DSECT
Top of page

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      SNTBK          System Name Table Block
0000    0 Dbl-Word     8 SNTASM0 (128)  General Information SNTBK/SHRBK
                                        queue lock (SNTSHRLK)
0400 1024 Dbl-Word     8 SNTASM1 (128)  Reserved
0800 2048 Dbl-Word     8 SNTASM2 (128)  Page Range Information Segment
                                        Space Member List
0C00 3072 Dbl-Word     8 SNTASM3 (128)  Member's Segment Space List
                                        Variable list of ASAs for Image
                                        Files
     |                                                          |
     |        SNTASM0 - General Information                     |
     |                - SNTBK/SHRBK queue lock (SNTSHRLK)       |
     |                                                          |
0000    0 Address      4 SNTFWDPT       Forward pointer to the next
                                        SNTBK.
0004    4 Address      4 SNTBCKPT       Backward pointer to the next
                                        SNTBK.
0008    8 Character   12 SNTNAMFL (0)   This field used to move the
                                        following two fields in HCPNSBWD.
0008    8 Character    8 SNTNAME        Name of the NSS, DCSS, image, or
                                        NLS.
0010   16 Signed       4 SNTFLAGS (0)   Flags for the SNTBK.
0010   16 Bitstring    1 SNTTYPFG       Type information flag.
          1... ....      SNTRSTD        X'80' SNTRSTD Indicates that this
                                        NSS or DCSS has restricted use
                                        and must have a NAMESAVE entry in
                                        the user's directory.
          .1.. ....      SNTCPUSE       X'40' SNTCPUSE Indicates that
                                        this is a CP NSS/DCSS - meaning
                                        CP will write to the parts of
                                        this NSS/DCSS with ranges defined
                                        as 'SC'.
          ..1. ....      SNTLSS         X'20' SNTLSS This bit indicates
                                        that this is a segment space
                                        definition that contains member
                                        saved segments.
          ...1 ....      SNTMSS         X'10' SNTMSS This bit indicates
                                        that this is a member saved
                                        segment definition. NOTES : If
                                        both SNTLSS and SNTMSS are off
                                        then this is a named saved
                                        segment.
          .... 1...      SNTNLS         X'08' SNTNLS This is an NLS.
          .... .1..      SNTIMG         X'04' SNTIMG This is an Image.
          .... ..1.      SNTSYS         X'02' SNTSYS This is an NSS.
          .... ...1      SNTSEG         X'01' SNTSEG This is a DCSS.
          1... ....      SNTRSTD        X'80' SNTRSTD Indicates that this
                                        NSS or DCSS has restricted use
                                        and must have a NAMESAVE entry in
                                        the user's directory.
          .1.. ....      SNTCPUSE       X'40' SNTCPUSE Indicates that
                                        this is a CP NSS/DCSS - meaning
                                        CP will write to the parts of
                                        this NSS/DCSS with ranges defined
                                        as 'SC'.
          ..1. ....      SNTLSS         X'20' SNTLSS This bit indicates
                                        that this is a segment space
                                        definition that contains member
                                        saved segments.
          ...1 ....      SNTMSS         X'10' SNTMSS This bit indicates
                                        that this is a member saved
                                        segment definition. NOTES : If
                                        both SNTLSS and SNTMSS are off
                                        then this is a named saved
                                        segment.
          .... 1...      SNTNLS         X'08' SNTNLS This is an NLS.
          .... .1..      SNTIMG         X'04' SNTIMG This is an Image.
          .... ..1.      SNTSYS         X'02' SNTSYS This is an NSS.
          .... ...1      SNTSEG         X'01' SNTSEG This is a DCSS.
0011   17 Bitstring    1 SNTSTAFG       Status information flag.
          .... .1..      SNTABEND       X'04' SNTABEND This bit indicates
                                        that an abend should be issued
                                        when the Auxiliary Storage
                                        Manager or Real Storage Manager
                                        in use counts are not the same.
          .... ...1      SNTPENDP       X'01' SNTPENDP This bit indicates
                                        that the NSS, DCSS, image, or NLS
                                        file should be purged when the
                                        total user count goes to zero.
          The following are the flags that indicate status.
       The field below, SNTENVFG, is kept in this block for
       compatibility only. It has been superceded by SNTMENVG.
       The values in this field should not be used in code other
       than the compatibility code currently referencing it.
       This field is defined to contain the virtual machine mode
       in which the NSS was saved. It therefore can have only
       one value.
       The field that supercedes this one, SNTMENVF/SNTMENVG,
       was defined as indicating which virtual machine modes
       were specified on the DEFSYS command. It now is defined
       as indicating in which mode(s) the NSS can be IPLed.
0012   18 Bitstring    1 SNTENVFG       Flag information byte
          00000001       SNT370MD       X'01' SNT370MD Indicates a 370
                                        mode machine
          00000002       SNTESAMD       X'02' SNTESAMD Indicates an
                                        ESA-370 mode machine
          00000004       SNTXCMD        X'04' SNTXCMD Indicates an ESA/XC
                                        mode machine
0013   19 Bitstring    1 SNTTYPF2       Type information byte 2.
          1... ....      SNTSHWRT       X'80' SNTSHWRT Indicates that
                                        there at least one shared
                                        writeable page range (SW or SN).
          .1.. ....      SNTVMGRP       X'40' SNTVMGRP Indicates that a
                                        VMGROUP attribute is assigned to
                                        this NSS.
          ..1. ....      SNTLNSHR       X'20' SNTLNSHR Indicates that any
                                        user is allowed to load an
                                        exclusive version of this saved
                                        segment. Note that this bit is
                                        only valid for DCSS and segment
                                        space SNTBKs.
        To update the SNTUSRSH or SNTUSREX count for NSSs or
        saved segments the SNTBK-SHRBK Queue lock (SNTSHRLK)
        must be held exclusively.
0014   20 Signed       4 SNTUSRSH       Count of NSS or DCSS users in
                                        shared mode or count of all users
                                        of an image library.
0018   24 Signed       4 SNTUSREX       Count of NSS or DCSS users in
                                        exclusive mode. NOTES : SNTUSRSH
                                        + SNTUSREX = The number of loads
                                        of this name. This is the number
                                        of SHRBKs on this SNTBK's SHRBK
                                        chain.
001C   28 Address      4 SNTSTLPT       Pointer to the STLBK. It contains
                                        PGMBK info
0020   32 Address      4 SNTSDFBK       Pointer to the SDFBK. Used to
                                        communicate with the SDF system.
             The following field SNTCOUNT is used to allow a move
      of the following fields in HCPNSBWD:
       SNTMINSZ, SNTRNGCT, SNTDESCT, SNTENVCT, SNTKEYCT, SNTSTRCT,
       SNTNDTCT, SNTPRFLG, Reserved byte, SNTPREGS
0024   36 Character   32 SNTCOUNT (0)
0024   36 Signed       4 SNTMINSZ       Indicates the minimum size in
                                        which the NSS can be IPLed.
0028   40 Signed       4 SNTRNGCT       Count of valid page range entries
                                        for an NSS or DCSS.
002C   44 Signed       4 SNTDESCT       Count of descriptor pages defined
                                        for an NSS, DCSS, image, or NLS
                                        file.
0030   48 Signed       4 SNTENVCT       Count of environment pages for an
                                        NSS.
0034   52 Signed       4 SNTKEYCT       Count of key pages for an NSS or
                                        DCSS.
0038   56 Signed       4 SNTSTRCT       Count of storage pages saved for
                                        an NSS, DCSS, image, or NLS file.
003C   60 Signed       4 SNTNDTCT       Count of storage pages defined
                                        with the no-data-saved attribute.
                                        This count is not calculated
                                        until the NSS or DCSS is saved.
                                        The total number of pages defined
                                        is SNTSTRCT+SNTNDTCT
0040   64 Bitstring    1 SNTPRFLG       PARMREGS flags
          1... ....      SNTPRDEF       X'80' SNTPRDEF PARMREGS OPTION
                                        SPECIFIED ON DEFSYS
          .1.. ....      SNTPRNO        X'40' SNTPRNO PARMREGS=NONE
                                        SPECIFIED ON DEFSYS
          1... ....      SNTPRDEF       X'80' SNTPRDEF PARMREGS OPTION
                                        SPECIFIED ON DEFSYS
          .1.. ....      SNTPRNO        X'40' SNTPRNO PARMREGS=NONE
                                        SPECIFIED ON DEFSYS
0041   65 Bitstring    1 *              Reserved for IBM use
0042   66 Bitstring    2 SNTPREGS (0)   PARMREGS registers
0042   66 Signed       1 SNTPRBEG       PARMREGS beginning register
0043   67 Signed       1 SNTPREND       PARMREGS ending register
0044   68 Address      4 SNTSHRPT       Forward anchor for SHRBK chain.
0048   72 Address      4 SNTCPNTE       CP Notification Address - this
                                        address will be called each time
                                        a virtual machine releases the
                                        system data file.
          The following definition of SNTMEMSR is for the
                          31-bit format
004C   76 Character   12 SNTMEMSR (0)
004C   76 Signed       2 SNTMEMCT       Count of member saved segments
                                        within this segment space. This
                                        field is only valid if SNTLSS is
                                        on. This field indicates the
                                        number of member saved segment
                                        directory entries located in the
                                        directory area (SNTASM2 &
                                        SNTASM3). It may not be larger
                                        than SNTMAXCT.
004E   78 Signed       2 *              Reserved for IBM use
0050   80 Signed       4 SNTSTPAG       The lowest page defined for this
                                        segment. This page number has not
                                        been rounded down to the nearest
                                        megabyte boundary for segment
                                        spaces.
0054   84 Signed       4 SNTENPAG       The highest page defined for this
                                        segment. This page number has not
                                        been rounded up to the nearest
                                        megabyte boundary for segment
                                        spaces.
0058   88 Signed       4 *              Reserved for IBM use
005C   92 Address      4 SNTCPNTL       CP Notification Address - this
                                        address will be called when the
                                        last virtual machine releases the
                                        system data file.
0060   96 Address      4 SNTNOTAM       CP Notification Address - this
                                        address will be called when a
                                        saved segment is purged.
0064  100 Signed       4 *              Reserved for IBM use.
0068  104 Bitstring    1 SNTMENVF       Flag used to indicate the virtual
                                        machine environments in which the
                                        NSS can be IPLed.
0069  105 Bitstring    1 * (7)          Reserved for IBM use.
          Redefinition of SNTMEMSR for 64-bit format SNTBK
      SNTMSRG is used to move the following fields in HCPNSBWD:
             SNTMEMCT, Reserved field, SNTSTPGG, SNTENPGG
004C   76 Character   20 SNTMSRG (0)
004C   76 Signed       2 *              SNTMEMCT
004E   78 Signed       2 *              Reserved for IBM use
0050   80 Dbl-Word     8 SNTSTPGG       Lowest page for this segment
0058   88 Dbl-Word     8 SNTENPGG       Highest page for this segment
        To update the SNTLODCG count for NSSs or saved segments
        the SNTBK-SHRBK Queue lock (SNTSHRLK) must be held
        exclusively.
0060   96 Signed       4 SNTLODCG       The number of loads via this
                                        segment space. This is the number
                                        of SHRBKs that point to this
                                        segment space. This count is only
                                        valid if SNTLSS is on.
0064  100 Address      4 SNTCPNTG       CP Notification Address - this
                                        address will be called when the
                                        last virtual machine releases the
                                        system data file
0068  104 Address      4 SNTNOTAG       CP Notification Address - this
                                        address will be called when a
                                        saved segment is purged
006C  108 Bitstring    1 SNTMENVG       Flag used to indicate the virtual
                                        machine environments in which the
                                        NSS can be IPLed
          1... ....      SNTMULT        X'80' SNTMULT This NSS can be
                                        IPLed in more than one virtual
                                        machine mode.
          .... 1...      SNTZMM         X'08' SNTZMM This bit indicates
                                        the z-arch virtual machine can
                                        IPL this NSS.
          .... .1..      SNTXCMM        X'04' SNTXCMM This bit indicates
                                        the ESA/XC virtual machine can
                                        IPL this NSS.
          .... ..1.      SNTESAMM       X'02' SNTESAMM This bit indicates
                                        the ESA-370 virtual machine can
                                        IPL this NSS.
          .... ...1      SNT370MM       X'01' SNT370MM This bit indicates
                                        the System/370 virtual machine
                                        can IPL this NSS.
006D  109 Bitstring    1 * (3)          Reserved for IBM use
            End of redefinitions for 64-bit format SNTBK
                    SNTBK/SHRBK queue lock (SNTSHRLK)
                    ******************************---
         Lock type: This is a formal shared or exclusive lock
         Resource serialized: This lock manages the SHRBK queue
         chained from the SNTBK. The lock will be obtained
         shared when scanning the queue and exclusive when
         adding to, or deleting from, the queue. This lock is
         also used to serialize the following SNTBK
         'use-counts': SNTUSRSH, SNTUSREX, SNTLODCG. The lock
         must be obtained exclusive when updating these counts.
         Notes      : If the Saved Segment SNTBK queue or Named Saved
         System SNTBK queue lock is held exclusively then the
         SNTBK/SHRBK lock does not need to be obtained to add/
         remove a SHRBK or increment/decrement the
         'use-counts'.
         See the general comments in HCPNSUBK COPY file for
         detailed Saved Segment or NSS locking information.
0070  112 Dbl-Word     8 SNTSHRLK (3)   SNTBK/SHRBK queue defer lock
0088  136 Dbl-Word     8 SNTPURID       User id who issued PURGE command
                                        while SAVESEG/SAVESYS command is
                                        processing.
0090  144 Address      4 *              Reserved for IBM use
0094  148 Address      4 SNTXBLBK       Address of XBLBK for NSSs
0098  152 Address      4 SNTENVPG       Address of environment page. This
                                        is a System Virtual address.
009C  156 Address      4 SNTASCBK       Address of ASCBK for this space
00A0  160 Bitstring    4 SNTTODLD       TOD(0-31) when image was loaded
00A4  164 Bitstring    4 *              Reserved for IBM use
00A8  168 Character    8 SNTMARKR       Eye-catcher
                                        C'>>SNT<<<'
004C   76 Signed       2 SNTLOGCT       Count of segment spaces
                                        containing this member save
                                        segment. This field is only valid
                                        if SNTMSS is on. This field
                                        indicates the number of segment
                                        space directory entries located
                                        in the directory area (SNTASM3).
                                        It may not be larger than
                                        SNTMAXCT.
                          End of SNTASM0
     |                                                          |
     | SNTASM2 - Page Range Information                         |
     |                    OR                                    |
     |           Segment Space Member List                      |
     |                                                          |
          Redefinition of SNTRANGE for 31-bit Page Range
          The page range will be in the form SSSPP0FF
                where  SSS  = segment number
                        PP  = page number
                        0   = always 0
                        FF  = flag byte
0800 2048 Dbl-Word     8 SNTRANGE       A pair of start/end page ranges.
0800 2048 Signed       4 SNTRANS        First page of range. This field
                                        for NSSs and DCSSs will contain a
                                        flag in the rightmost byte.
0804 2052 Signed       4 SNTRANE        Last page of range.
               Redefinitions for 64-bit Page Range
          The page range will be in the form RRRRRRRRSSSPP0FF
                where  RRRRRRRR  = region number
                            SSS  = segment number
                             0   = always 0
                             FF  = flag byte
0800 2048 Bitstring   16 SNTRANGG       A pair of start/end page ranges.
          .1.. ....      SNTPRMXG       64 SNTPRMXG The maximum number of
                                        page range entries plus one entry
                                        for the fence for NSSs and DCSSs.
                                        Images have only one page range.
0800 2048 Dbl-Word     8 SNTRANSG       First page of range. This field
                                        for NSSs and DCSSs will contain a
                                        flag in the rightmost byte.
0808 2056 Dbl-Word     8 SNTRANEG       Last page of range.
0800 2048 Bitstring    7 SNTRSNOG       The start page range minus the
                                        flag byte. The page range will be
                                        in the form RRRRRRRRSSSPP0FF:
                                        where RRRRRRRR = region number
                                        SSS = segment number 0 = always 0
                                        FF = flag byte
0807 2055 Bitstring    1 SNTRGFGG       Page range storage type flag for
                                        NSSs and DCSSs.
          .... ...1      SNTEXCL        X'01' SNTEXCL This bit indicates
                                        segments that may not be shared
                                        among several users. Each user
                                        gets a separate copy of this
                                        segment.
          .... ..1.      SNTPROT        X'02' SNTPROT This bit indicates
                                        page ranges that are page
                                        protected. Users may access these
                                        pages only in read-only mode.
          .... .1..      SNTNDAT        X'04' SNTNDAT This bit indicates
                                        page ranges whose data is not
                                        saved into the SDF (no data).
         The following describes how page descriptor codes
              correspond to settings of SNTRGFGG.
 CODE SNTRGFGG SNTNDAT  SNTPROT                    SNTEXCL
 ---- -------- -------  -------                    -------
 SW   000     0=data   0=unprotected (read/write) 0=shared
 EW   001     0=data   0=unprotected (read/write) 1=exclusive
 SR   010     0=data   1=protected   (read-only)  0=shared
 ER   011     0=data   1=protected   (read-only)  1=exclusive
 SN   100     1=nodata 0=unprotected (read/write) 0=shared
 EN   101     1=nodata 0=unprotected (read/write) 1=exclusive
 SC   110     1=nodata 1=protected   (read-only)  0-shared
      111     (reserved)
          00000000       SNTRNGSW       0 Range flag value for 'SW'
          00000001       SNTRNGEW       SNTEXCL Range flag value for 'EW'
          00000002       SNTRNGSR       SNTPROT Range flag value for 'SR'
          00000003       SNTRNGER       SNTPROT+SNTEXCL Range flag value
                                        for 'ER'
          00000004       SNTRNGSN       SNTNDAT Range flag value for 'SN'
          00000005       SNTRNGEN       SNTNDAT+SNTEXCL Range flag value
                                        for 'EN'
          00000006       SNTRNGSC       SNTNDAT+SNTPROT Range flag value
                                        for 'SC'
          00000007       SNTRNGR2       SNTNDAT+SNTPROT+SNTEXCL Reserved
            End of redefinitions for 64-bit Page Range
     |                                                          |
     |              Segment Space Member List                   |
     |                                                          |
                      Individual Member Entry
      Notes      : This is a list of entries that can overlay both
                        SNTASM2 and SNTASM3.
0800 2048 Character   32 SNTMEMBR       Member entry
              Redefinition of Member Entry (SNTMEMBR)
                       for 31-bit format
0800 2048 Character   16 SNTMEMDA (0)   Used to move the next three
                                        fields
0800 2048 Character    8 SNTMSSNM       Name of the member saved segment
0808 2056 Signed       4 SNTMEMST       First page of range. This field
                                        will contain status information
                                        in the rightmost byte. The page
                                        number will be in form:
                    SSSPP0FF, where SSS = segment number
                                    PP  = page number
                                    0   = always 0
                                    FF  = status byte
080C 2060 Signed       4 SNTMEMEN       Last page of range
0810 2064 Address      4 SNTMSSA        Address of the SNTBK defining the
                                        member saved segment.
0814 2068 Signed       4 *              Reserved for IBM use
0818 2072 Dbl-Word     8 *              Reserved for IBM use
          00000020       SNTNTSZM       *-SNTMSSNM Length of a member
                                        saved seg entry
               Redefinition of Member Entry (SNTMEMBR)
                        for 64-bit format
0800 2048 Character   24 SNTMEMDG (0)   Used to move the next 3 fields in
                                        HCPNSBWD
0800 2048 Character    8 SNTMSSNG       Name of the member saved segment
0808 2056 Dbl-Word     8 SNTMEMSG       First page of range. This field
                                        will contain status information
                                        in the rightmost byte. The page
                                        number will be in form:
                    RRRRRRRRSSSPP0FF:
                        where RRRRRRRR  = region number
                                   SSS  = segment number
                                    PP  = page number
                                    0   = always 0
                                    FF  = status byte
0810 2064 Dbl-Word     8 SNTMEMEG       Last page of range
0818 2072 Address      4 SNTMSSAG       Address of the SNTBK defining the
                                        member saved segment.
081C 2076 Signed       4 *              Reserved for IBM use
0808 2056 Bitstring    7 SNTMSPG        Starting page number for the
                                        member
080F 2063 Bitstring    1 SNTMSTAG       Member saved segment status byte.
          .... .1..      SNTMQNTF       X'04' SNTMQNTF Flag to indicate
                                        this entry not found during QUERY
                                        NAMES command processing
          .... ..1.      SNTMSAVD       X'02' SNTMSAVD This member saved
                                        segment has been saved
          .... ...1      SNTMPENP       X'01' SNTMPENP This member saved
                                        segment is in pending
                           End of SNTASM2
     |                                                          |
     | SNTASM3 - Member's Segment Space List                    |
     |         - Variable list of ASAs for Image Files          |
     |                                                          |
0C00 3072 Character   16 SNTLGSEG       Segment Space Entry
                   Individual Segment Space Entry
0C00 3072 Character    8 SNTLSSNM       Name of the segment space
0C08 3080 Address      4 SNTLSSA        Address of the segment space's
                                        SNTBK. This field is zero if the
                                        segment space is not being used.
                                        WARNING - this field may be
                                        inaccurate under certain
                                        circumstances (like SNTBKs of
                                        members that were defined using
                                        the 'SAME' option). It is
                                        recommended that the segment
                                        space be located through SHRLSSA
                                        and compared be done on the SNTBK
                                        names, not with this address.
0C0C 3084 Bitstring    1 SNTLSTAT       Segment space status byte
          .... .1..      SNTLQNTF       X'04' SNTLQNTF Flag to indicate
                                        this entry not found during QUERY
                                        NAMES command processing.
          .... ..1.      SNTLOPEN       X'02' SNTLOPEN Segment space
                                        found open don't compress.
          .... ...1      SNTLPENP       X'01' SNTLPENP This segment space
                                        is in pending purge status.
0C0D 3085 Bitstring    3 SNTLSSCT       Number of segment space SNTBKs by
                                        this name pointing to this member
                                        SNTBK. Note 3 bytes are enough as
                                        each SNTBK occupies a full page
                                        and we can never have X'FFFFFF'
                                        SNTBKs.
          00000010       SNTNTSZL       *-SNTLSSNM The size of a segment
                                        space directory entry.
                  End of Member's Segment Space List
                 Variable list of ASAs for Image Files
          0000000A       SNTAPMAX       10 The maximum number of address
                                        entries in this ASA/virtual
                                        address table for an image or NLS
                                        file.
0C00 3072 Address      4 SNTASALT       Address of the next page in the
                                        ASA/virtual address table. This
                                        field applies only to image and
                                        NLS files.
          00000C04       SNTNASA        * Next ASA in the table for image
                                        files.
             End of Variable List of ASAs for Image Files
                           End of SNTASM3

          
*** SNTBK - System Name Table Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       SNTASM0                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 400 |                                                       |
*     =                       SNTASM1                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 800 |                                                       |
*     =                       SNTASM2                         =
*     |                                                       |
*     +-------------------------------------------------------+
* C00 |                                                       |
*     =                       SNTASM3                         =
*     |                                                       |
*     +-------------------------------------------------------+
*1000
*
*** SNTBK - System Name Table Block
          
*** Overlay for SNTASM0 in SNTBK
*
*     +---------------------------+---------------------------+
*   0 |         SNTFWDPT          |         SNTBCKPT          |
*     +---------------------------+---------------------------+
*   8 |                       SNTNAME                         |
*     +------+------+------+------+---------------------------+
*  10 |:TYPFG|:STAFG|:ENVFG|:TYPF2|         SNTUSRSH          |
*     +------+------+------+------+---------------------------+
*  18 |         SNTUSREX          |         SNTSTLPT          |
*     +---------------------------+---------------------------+
*  20 |         SNTSDFBK          |         SNTMINSZ          |
*     +---------------------------+---------------------------+
*  28 |         SNTRNGCT          |         SNTDESCT          |
*     +---------------------------+---------------------------+
*  30 |         SNTENVCT          |         SNTKEYCT          |
*     +---------------------------+---------------------------+
*  38 |         SNTSTRCT          |         SNTNDTCT          |
*     +------+------+------+------+---------------------------+
*  40 |:PRFLG|//////|:PRBEG|:PREND|         SNTSHRPT          |
*     +------+------+------+------+-------------+-------------+
*  48 |         SNTCPNTE          |  SNTMEMCT   |/////////////|
*     +---------------------------+-------------+-------------+
*  50 |         SNTSTPAG          |         SNTENPAG          |
*     +---------------------------+---------------------------+
*  58 |///////////////////////////|         SNTCPNTL          |
*     +---------------------------+---------------------------+
*  60 |         SNTNOTAM          |///////////////////////////|
*     +------+--------------------+---------------------------+
*  68 |:MENVF|////////////////////////////////////////////////|
*     +------+------------------------------------------------+
*  70
*
*** Overlay for SNTASM0 in SNTBK
          
*** Overlay for SNTMEMSR in SNTBK
*
*                                 +-------------+-------------+
*  48 ...                      4C |/////////////|/////////////|
*                                 +-------------+-------------+
*  50
*
*** Overlay for SNTMEMSR in SNTBK
          
*** Overlay for SNTSTPAG in SNTBK
*
*     +-------------------------------------------------------+
*  50 |                       SNTSTPGG                        |
*     +-------------------------------------------------------+
*  58 |                       SNTENPGG                        |
*     +---------------------------+---------------------------+
*  60 |         SNTLODCG          |         SNTCPNTG          |
*     +---------------------------+------+--------------------+
*  68 |         SNTNOTAG          |:MENVG|////////////////////|
*     +---------------------------+------+--------------------+
*  70 |                                                       |
*     =                       SNTSHRLK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  88 |                       SNTPURID                        |
*     +---------------------------+---------------------------+
*  90 |///////////////////////////|         SNTXBLBK          |
*     +---------------------------+---------------------------+
*  98 |         SNTENVPG          |         SNTASCBK          |
*     +---------------------------+---------------------------+
*  A0 |         SNTTODLD          |///////////////////////////|
*     +---------------------------+---------------------------+
*  A8 |                       SNTMARKR                        |
*     +-------------------------------------------------------+
*  B0
*
*** Overlay for SNTSTPAG in SNTBK
          
*** Overlay for SNTMEMCT in SNTBK
*
*                                 +-------------+
*  48 ...                      4C |  SNTLOGCT   | 4E
*                                 +-------------+
*
*** Overlay for SNTMEMCT in SNTBK
          
*** Overlay for SNTASM2 in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                       SNTRANGE                        |
*     +-------------------------------------------------------+
* 808
*
*** Overlay for SNTASM2 in SNTBK
          
*** Overlay for SNTRANGE in SNTBK
*
*     +---------------------------+---------------------------+
* 800 |         SNTRANS           |         SNTRANE           |
*     +---------------------------+---------------------------+
* 808
*
*** Overlay for SNTRANGE in SNTBK
          
*** Overlay for SNTASM2 in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                       SNTRANGG                        |
*     |                                                       |
*     +-------------------------------------------------------+
* 810
*
*** Overlay for SNTASM2 in SNTBK
          
*** Overlay for SNTRANGG in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                       SNTRANSG                        |
*     +-------------------------------------------------------+
* 808 |                       SNTRANEG                        |
*     +-------------------------------------------------------+
* 810
*
*** Overlay for SNTRANGG in SNTBK
          
*** Overlay for SNTRANSG in SNTBK
*
*     +------------------------------------------------+------+
* 800 |                   SNTRSNOG                     |:RGFGG|
*     +------------------------------------------------+------+
* 808
*
*** Overlay for SNTRANSG in SNTBK
          
*** Overlay for SNTASM2 in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                                                       |
*     =                       SNTMEMBR                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 820
*
*** Overlay for SNTASM2 in SNTBK
          
*** Overlay for SNTMEMBR in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                       SNTMSSNM                        |
*     +---------------------------+---------------------------+
* 808 |         SNTMEMST          |         SNTMEMEN          |
*     +---------------------------+---------------------------+
* 810 |         SNTMSSA           |///////////////////////////|
*     +---------------------------+---------------------------+
* 818 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
* 820
*
*** Overlay for SNTMEMBR in SNTBK
          
*** Overlay for SNTMEMBR in SNTBK
*
*     +-------------------------------------------------------+
* 800 |                       SNTMSSNG                        |
*     +-------------------------------------------------------+
* 808 |                       SNTMEMSG                        |
*     +-------------------------------------------------------+
* 810 |                       SNTMEMEG                        |
*     +---------------------------+---------------------------+
* 818 |         SNTMSSAG          |///////////////////////////|
*     +---------------------------+---------------------------+
* 820
*
*** Overlay for SNTMEMBR in SNTBK
          
*** Overlay for SNTMEMSG in SNTBK
*
*     +------------------------------------------------+------+
* 808 |                    SNTMSPG                     |:MSTAG|
*     +------------------------------------------------+------+
* 810
*
*** Overlay for SNTMEMSG in SNTBK
          
*** Overlay for SNTASM3 in SNTBK
*
*     +-------------------------------------------------------+
* C00 |                       SNTLGSEG                        |
*     |                                                       |
*     +-------------------------------------------------------+
* C10
*
*** Overlay for SNTASM3 in SNTBK
          
*** Overlay for SNTLGSEG in SNTBK
*
*     +-------------------------------------------------------+
* C00 |                       SNTLSSNM                        |
*     +---------------------------+------+--------------------+
* C08 |         SNTLSSA           |:LSTAT|     SNTLSSCT       |
*     +---------------------------+------+--------------------+
* C10
*
*** Overlay for SNTLGSEG in SNTBK
          
*** Overlay for SNTASM3 in SNTBK
*
*     +---------------------------+
* C00 |         SNTASALT          | C04
*     +---------------------------+
*
*** Overlay for SNTASM3 in SNTBK

 
Symbol         Dspl Value
-------------- ---- -----
SNTABEND       0011 04
SNTAPMAX       0C0D 0000000A
SNTASALT       0C00
SNTASCBK       009C
SNTASM0        0000
SNTASM1        0400
SNTASM2        0800
SNTASM3        0C00
SNTBCKPT       0004
SNTCOUNT       0024
SNTCPNTE       0048
SNTCPNTG       0064
SNTCPNTL       005C
SNTCPUSE       0010 40
SNTCPUSE       0010 40
SNTDESCT       002C
SNTENPAG       0054
SNTENPGG       0058
SNTENVCT       0030
SNTENVFG       0012
SNTENVPG       0098
SNTESAMD       0012 00000002
SNTESAMM       006C 02
SNTEXCL        0807 01
SNTFLAGS       0010
SNTFWDPT       0000
SNTIMG         0010 04
SNTIMG         0010 04
SNTKEYCT       0034
SNTLGSEG       0C00
SNTLNSHR       0013 20
SNTLODCG       0060
SNTLOGCT       004C
SNTLOPEN       0C0C 02
SNTLPENP       0C0C 01
SNTLQNTF       0C0C 04
SNTLSS         0010 20
SNTLSS         0010 20
SNTLSSA        0C08
SNTLSSCT       0C0D
SNTLSSNM       0C00
SNTLSTAT       0C0C
SNTMARKR       00A8
SNTMEMBR       0800
SNTMEMCT       004C
SNTMEMDA       0800
SNTMEMDG       0800
SNTMEMEG       0810
SNTMEMEN       080C
SNTMEMSG       0808
SNTMEMSR       004C
SNTMEMST       0808
SNTMENVF       0068
SNTMENVG       006C
SNTMINSZ       0024
SNTMPENP       080F 01
SNTMQNTF       080F 04
SNTMSAVD       080F 02
SNTMSPG        0808
SNTMSRG        004C
SNTMSS         0010 10
SNTMSS         0010 10
SNTMSSA        0810
SNTMSSAG       0818
SNTMSSNG       0800
SNTMSSNM       0800
SNTMSTAG       080F
SNTMULT        006C 80
SNTNAME        0008
SNTNAMFL       0008
SNTNASA        0C00 00000C04
SNTNDAT        0807 04
SNTNDTCT       003C
SNTNLS         0010 08
SNTNLS         0010 08
SNTNOTAG       0068
SNTNOTAM       0060
SNTNTSZL       0C0D 00000010
SNTNTSZM       0818 00000020
SNTPENDP       0011 01
SNTPRBEG       0042
SNTPRDEF       0040 80
SNTPRDEF       0040 80
SNTPREGS       0042
SNTPREND       0043
SNTPRFLG       0040
SNTPRMXG       0800 40
SNTPRNO        0040 40
SNTPRNO        0040 40
SNTPROT        0807 02
SNTPURID       0088
SNTRANE        0804
SNTRANEG       0808
SNTRANGE       0800
SNTRANGG       0800
SNTRANS        0800
SNTRANSG       0800
SNTRGFGG       0807
SNTRNGCT       0028
SNTRNGEN       0807 00000005
SNTRNGER       0807 00000003
SNTRNGEW       0807 00000001
SNTRNGR2       0807 00000007
SNTRNGSC       0807 00000006
SNTRNGSN       0807 00000004
SNTRNGSR       0807 00000002
SNTRNGSW       0807 00000000
SNTRSNOG       0800
SNTRSTD        0010 80
SNTRSTD        0010 80
SNTSDFBK       0020
SNTSEG         0010 01
SNTSEG         0010 01
SNTSHRLK       0070
SNTSHRPT       0044
SNTSHWRT       0013 80
SNTSTAFG       0011
SNTSTLPT       001C
SNTSTPAG       0050
SNTSTPGG       0050
SNTSTRCT       0038
SNTSYS         0010 02
SNTSYS         0010 02
SNTTODLD       00A0
SNTTYPFG       0010
SNTTYPF2       0013
SNTUSREX       0018
SNTUSRSH       0014
SNTVMGRP       0013 40
SNTXBLBK       0094
SNTXCMD        0012 00000004
SNTXCMM        006C 04
SNTZMM         006C 08
SNT370MD       0012 00000001
SNT370MM       006C 01