Programming Interface Information:
This information is NOT intended to be used as Programming Interfaces of z/VM. |
SFNDX
Control Block Contents
SFNDX DSECT
Cross Reference (Contains links to field and bit definitions)
SFNDX Prolog
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
SFNDX DSECT
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
*** SFNDX - CHECKPOINT SPOOL FILE POINTERS * * +-------------------------------------------------------+ * 0 | SFNTSTMP | * +-------------------------------------------------------+ * 8 | | * = SFNASA = * | | * +-------------------------------------------------------+ * *** SFNDX - CHECKPOINT SPOOL FILE POINTERS
SFNDX Cross Reference
Symbol Dspl Value -------------- ---- ----- SFNASA 0008 SFNASATL 1000 SFNCCEND SFNCCEND 1000 SFNSCNT 1000 SFNCCEND SFNSIZE 1000 00000200 SFNTSTMP 0000
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