MODHDCB Back to Index page
 
Prolog 
Control Block Contents 
   MODHDCB 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.


  MODHDCB Prolog Top of page
 
 NAME       : MODHDCB
 DESCRIPTION: Module Header Control Block
 DSECT      : MODHDCB
 NOTES      : This macro describes the first record,
              called the header record, in a CMS Module file.
              This header is 80 bytes long and exists in
              variable format record file system module files
              and all byte file system module files.
 
 
  MODHDCB Control Block Content Top of page
 

 MODHDCB DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure MODHDCB Module Header Control Block 0000 0 Character 40 NUCONMAP 1st 40 bytes mapped by NUCON 0000 0 Signed 4 STARTADR Start Location 0004 4 Signed 4 XFRSTLOC Beginning location in storage 0008 8 Signed 4 XLASTLOC Ending location in storage 000C 12 Signed 4 XLOCCNT Location counter 0010 16 Character 16 RSVD0 Reserved 0020 32 Bitstring 4 XLDRFLGS Module flag 0020 32 Bitstring 1 XLDRNOER .... .1.. NOERASE X'04' NOERASE .... ...1 SYSTEM X'01' SYSTEM 0021 33 Bitstring 1 XLDRSTRN 1... .... STRINIT X'80' STRINIT 0022 34 Bitstring 2 RESERVED 0024 36 Character 4 RSVD1 Reserved and must be zero 0028 40 Bitstring 2 TABLENT # Loader Table Entries 002A 42 Character 1 POFLAG X'80' nucon uses as UNRES flag .1.. .... ISAPO X'40' ISAPO Module is a program object 002B 43 Bitstring 1 MODFLAG Module flag 1... .... NOLOADMF X'80' NOLOADMF Indicates 'No Load Map' .1.. .... CLEAROPT X'40' CLEAROPT CLEAR option flag ..1. .... MODDOS X'20' MODDOS Generated with DOS option ...1 .... MODALL X'10' MODALL Generated with ALL option .... ..1. MAP24BYT X'02' MAP24BYT Map entries are 24 bytes .... ...1 POSTXA X'01' POSTXA Module gen'd by CMS 5.5 or later 002C 44 Bitstring 1 MODEFLAG AMODE/RMODE flag 1... .... AMODE31 X'80' AMODE31 Indicates an AMODE of 31 .1.. .... AMODE24 X'40' AMODE24 Indicates an AMODE of 24 11.. .... AMODEANY X'C0' AMODEANY Indicates an AMODE of ANY ..1. .... RMODEANY X'20' RMODEANY Indicates an RMODE of ANY ...1 .... RMODE24 X'10' RMODE24 Indicates an RMODE of 24 002D 45 Bitstring 1 RLDFLAG Relocation flag 1... .... RELODATA X'80' RELODATA RLD data does exist .1.. .... FORMAT31 X'40' FORMAT31 31 bit RLD entries ..1. .... TWORLD X'20' TWORLD 2 RLD recs in file ...1 .... CLEANMOD X'10' CLEANMOD Cleanup module at end of svc .... 1... FIXDTRNS X'08' FIXDTRNS Fixed transient area module 002E 46 Bitstring 1 ARCFLAG Architecture flag 1... .... INVLD370 X'80' INVLD370 370 architecture is invalid .1.. .... INVALXA X'40' INVALXA XA architecture is invalid ..1. .... INVALXC X'20' INVALXC XC architecture is invalid 002F 47 Bitstring 1 * Reserved 0030 48 Bitstring 2 RLDRECS Number of RLD records in the module 0032 50 Bitstring 2 LRLDBYTS Number of bytes in last rld record - bfs files only 0034 52 Signed 4 HISTSIZE Size of the history data in bytes - bfs files only 0038 56 Bitstring 2 ICATCH Module eye catcher for DMSEXC 003A 58 Bitstring 2 POREC First PO record number 0040 64 Dbl-Word 8 * (0) 00000040 MODHDLEN *-MODHDCB MODHDCB length in bytes 00000008 MODDBLEN (MODHDLEN+7)/8 MODHDCB length in dw
 
 
  MODHDCB Storage Layout Top of page
 
          
*** MODHDCB - Module Header Control Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       NUCONMAP                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  28
*
*** MODHDCB - Module Header Control Block
          
*** Overlay for NUCONMAP in MODHDCB
*
*     +---------------------------+---------------------------+
*   0 |         STARTADR          |         XFRSTLOC          |
*     +---------------------------+---------------------------+
*   8 |         XLASTLOC          |         XLOCCNT           |
*     +---------------------------+---------------------------+
*  10 |                        RSVD0                          |
*     |                                                       |
*     +---------------------------+---------------------------+
*  20 |         XLDRFLGS          | 24
*     +---------------------------+
*
*** Overlay for NUCONMAP in MODHDCB
          
*** Overlay for XLDRFLGS in MODHDCB
*
*     +------+------+-------------+---------------------------+
*  20 |:RNOER|:RSTRN|/////////////|          RSVD1            |
*     +------+------+------+------+------+------+------+------+
*  28 |  TABLENT    |POFLAG|:FLAG |:EFLAG|:FLAG |:FLAG |//////|
*     +-------------+------+------+------+------+------+------+
*  30 |  RLDRECS    |  LRLDBYTS   |         HISTSIZE          |
*     +-------------+-------------+---------------------------+
*  38 |   ICATCH    |   POREC     |///////////////////////////|
*     +-------------+-------------+---------------------------+
*  40
*
*** Overlay for XLDRFLGS in MODHDCB
 
 
  MODHDCB Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
AMODEANY       002C C0
AMODE24        002C 40
AMODE31        002C 80
ARCFLAG        002E
CLEANMOD       002D 10
CLEAROPT       002B 40
FIXDTRNS       002D 08
FORMAT31       002D 40
HISTSIZE       0034
ICATCH         0038
INVALXA        002E 40
INVALXC        002E 20
INVLD370       002E 80
ISAPO          002A 40
LRLDBYTS       0032
MAP24BYT       002B 02
MODALL         002B 10
MODDBLEN       0040 00000008
MODDOS         002B 20
MODEFLAG       002C
MODFLAG        002B
MODHDLEN       0040 00000040
NOERASE        0020 04
NOLOADMF       002B 80
NUCONMAP       0000
POFLAG         002A
POREC          003A
POSTXA         002B 01
RELODATA       002D 80
RESERVED       0022
RLDFLAG        002D
RLDRECS        0030
RMODEANY       002C 20
RMODE24        002C 10
RSVD0          0010
RSVD1          0024
STARTADR       0000
STRINIT        0021 80
SYSTEM         0020 01
TABLENT        0028
TWORLD         002D 20
XFRSTLOC       0004
XLASTLOC       0008
XLDRFLGS       0020
XLDRNOER       0020
XLDRSTRN       0021
XLOCCNT        000C
 
This information is based on z/VM 6.3.0.
Last updated on 22 May 2013 at 13:50:08 EDT.
Copyright IBM Corporation, 1990, 2013