FORBK Back to Index page
 
Prolog 
Control Block Contents 
   FORBK DSECT
   FORCTBL 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.


  FORBK Prolog Top of page
 
 NAME       : HCPFORBK
 DESCRIPTION: The FOR control block.
 DSECT      : FORBK
 FUNCTION   : Provides a mapping of the FORBK control block containing
              the *ASYNCMD connection table for a virtual configuration.
 LOCATED BY : The VMDFORBK field in the base VMDBK points to the FORBK
 CREATED BY : Entry point HCPASYCN will create the FORBK on the first connection
              to the *ASYNCMD system service.
 DELETED BY : The following entry points:
              HCPFORSP - End of FOR command handler
              HCPFORRT - Reset handler
 REFERENCES : FORCTBL - mapping of a single *ASYNCMD connection table entry
 SERIALIZED : When accessing the FORBK, the lock hierarchy is
              as follows: first obtain the IUCV lock, then
              get the FORBK lock.
 RELOCATION CONSIDERATIONS : None
 COMPATIBILITY AND MIGRATION CONCERNS : None
 
 
  FORBK Control Block Content Top of page
 

 FORBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure FORBK The FOR control block. 0000 0 Dbl-Word 8 FORLOCK (3) FORBK Lock 0018 24 Bitstring 1 FORFLAG Flag byte 1... .... FORORPHN X'80' FORORPHN This FORBK is orphaned .1.. .... FORALLSP X'40' FORALLSP All slots in use are sever-pending 0019 25 Bitstring 1 * Reserved for future IBM use 001A 26 Signed 2 FORNXFRE The number of the next available slot in the *ASYNCMD connection table. Slots are numbered 0-7, if FORNXFRE is 8, then the table is full. 001C 28 Signed 2 FORMRCON The number of the most recently connected slot 001E 30 Signed 2 * Reserved for future IBM use 0020 32 Bitstring 8 FORTBL (2) *ASYNCMD connection table 00000060 FORSIZEB *-FORBK Size of FORBK in bytes 0000000C FORSIZE (FORSIZEB+7)/8 Size of FORBK in double words FORCTBL - mapping of a single *ASYNCMD connection table entry 00000008 FORECNT 8 Number of entries in the *ASYNCMD connection table
 FORCTBL DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure FORCTBL The FOR control block. 0000 0 Signed 2 FORCUPTH User-side path ID 0002 2 Signed 2 FORCAPTH *ASYNCMD-side path ID 0004 4 Signed 2 FORCUCTR Count of outstanding FOR commands 0006 6 Bitstring 1 FORCFLAG Flag byte 1... .... FORCSEVP X'80' FORCSEVP Path is sever-pending 0007 7 Bitstring 1 * Reserved for future IBM use 00000008 FORCSIZB *-FORCTBL Size in FORCTBL in bytes 00000001 FORCSIZE (FORCSIZB+7)/8 Size in FORCTBL in double words
 
 
  FORBK Storage Layout Top of page
 
          
*** FORBK - The FOR control block.
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       FORLOCK                         =
*     |                                                       |
*     +------+------+-------------+-------------+-------------+
*  18 |:FLAG |//////|  FORNXFRE   |  FORMRCON   |/////////////|
*     +------+------+-------------+-------------+-------------+
*  20 |                        FORTBL                         |
*     |                                                       |
*     +-------------------------------------------------------+
*  30
*
*** FORBK - The FOR control block.
          
*** FORCTBL - The FOR control block.
*
*     +-------------+-------------+-------------+------+------+
*   0 |  FORCUPTH   |  FORCAPTH   |  FORCUCTR   |:CFLAG|//////|
*     +-------------+-------------+-------------+------+------+
*   8
*
*** FORCTBL - The FOR control block.
 
 
  FORBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
FORALLSP       0018 40
FORCAPTH       0002
FORCFLAG       0006
FORCSEVP       0006 80
FORCSIZB       0007 00000008
FORCSIZE       0007 00000001
FORCUCTR       0004
FORCUPTH       0000
FORECNT        0020 00000008
FORFLAG        0018
FORLOCK        0000
FORMRCON       001C
FORNXFRE       001A
FORORPHN       0018 80
FORSIZE        0020 0000000C
FORSIZEB       0020 00000060
FORTBL         0020
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:50:35 EDT.
Copyright IBM Corporation, 1990, 2022