SFNDX | Back to Index page

| Prolog Control Block Contents SFNDX 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.

SFNDX Prolog | Top of page

     NAME       : HCPSFNDX
     DESCRIPTION: CHECKPOINT SPOOL FILE POINTERS
     DSECT      : SFNDX
     FUNCTION   : To point to the first map page (SPMBK) for each
                  spool file in the system.  The number of entries
                  in this table is determined by the size of the
                  warmstart area.  Each 4K page on the warmstart
                  cylinder allows for 1022 entries, one for each
                  possible spoolid.  If an entry contains a zero,
                  it indicates that the corresponding spoolid is
                  available for a new spool file.
     LOCATED BY : The SFNDX entries occupy contiguous pages of
                  system virtual storage. The first page of the
                  SFNDX is pointed to by SYSVSNDX in SYSCM.
     CREATED BY : The virtual pages reserved for the SFNDX
                  entries are cleared to zero when the system is
                  CLEAN started. They are reinitialized when
                  the system is WARM, FORCE, or COLD started
                  (only entries for system data files are
                  reinitialized for COLD starts).
                  During normal system processing, the SFNDX
                  entries are initialized by HCPSFSON when opening
                  a new spool file.
     DELETED BY : When a spool file is deleted, HCPSFRDR zeroes
                  out the corresponding SFNDX entry.  The storage
                  allocated for the SFNDX entries is never
                  deleted.
     RELOCATION CONSIDERATIONS : None

SFNDX Control Block Content | Top of page

     SFNDX DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SFNDX          CHECKPOINT SPOOL FILE POINTERS
    0000    0 Dbl-Word     8 SFNTSTMP       TIMESTAMP INFORMATION
    0008    8 Signed       4 SFNASA (1022)  SPMBK POINTERS
    1000 4096 Signed       4 SFNCCEND (0)
              SFNCCEND       SFNSCNT        1022 SFNSCNT NUMBER OF SLOTS
              SFNCCEND       SFNASATL       L'SFNASA*SFNSCNT SFNASATL Size of
                                            ASA area in bytes
              00000200       SFNSIZE        (*-SFNDX+7)/8 BLOCK SIZE IN
                                            DBLWDS

SFNDX Storage Layout | Top of page

    *** SFNDX - CHECKPOINT SPOOL FILE POINTERS
    *
    *     +-------------------------------------------------------+
    *   0 |                       SFNTSTMP                        |
    *     +-------------------------------------------------------+
    *   8 |                                                       |
    *     =                        SFNASA                         =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *
    *** SFNDX - CHECKPOINT SPOOL FILE POINTERS

SFNDX Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    SFNASA         0008
    SFNASATL       1000 SFNCCEND
    SFNCCEND       1000
    SFNSCNT        1000 SFNCCEND
    SFNSIZE        1000 00000200
    SFNTSTMP       0000

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:30:27 EDT.
Copyright IBM Corporation, 1990, 2020