Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (C)
Guardian Procedure Calls Reference Manual—522629-013
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CHECKPOINTMANY Procedure
(Superseded by CHECKPOINTMANYX Procedure )
<0:7> = 2 Takeover from primary; then <8:15> =
0 Primary process stopped
1 Primary process abnormally ended
2 Primarys process processor failed
3 Primary process called CHECKSWITCH
<0:7> = 3 Illegal parameter, then <8:15> =
1Error in
stack-origin parameter
n > 1 Error in word [n-2] (see “Considerations”)
stack-origin input
INT:ref:*
contains an address. CHECKPOINTMANY checkpoints the process’s data stack
from
stack-origin through the current tip-of-stack location (‘S’). A checkpoint
of the data stack defines a restart point for the backup process.
descriptors input
INT:ref:*
is an array that describes the items (data blocks or file synchronization blocks) to
be checkpointed. The first word of the array,
descriptors[0], is a count of the
number of items to be checkpointed. The rest of the array consists of pairs of
words, each pair describing one of the items. (See “Considerations.”)
Considerations
•
descriptors array form:
Following word zero,
descriptors consists of pairs of words.
+----------------------------------------+
descriptors[0] | number of items to be checkpointed |
|----------------------------------------|
[n] | |
|-------- descriptors pairs -----------|
[n+1] | |
|----------------------------------------|
. .
. .
If the first word of the pair contains -1, the pair describes a file synchronization
block item for the file whose file number is in the second word of the pair.
|----------------------------------------|
descriptors[n] | -1 = file sync block item for file |
|----------------------------------------|
[n+1] | file's filenum |
|----------------------------------------|
. .