GDSX (Extended General Device Support) Manual

DEVICE^HANDLER Example, Design
Extended General Device Support (GDSX) Manual—529931-001
5-22
Testing Failure at a ^WRITEREAD
had been no ^CHECKPOINT call, the task would have been restarted from its main
entry point.
If ^CHECKPOINT is called with type equal to 1, only the task’s stack image is
checkpointed to the backup. If the procedure is called with type equal to 2, the stack
image plus any memory pool buffers allocated by the task are checkpointed to the
Figure 5-6. Fault Tolerance in the DEVICE^HANDLER Example
WHILE (1)
DO
@RCV^BUF :=
GETEXTPOOL (...
TAKEOVER :=
FALSE
^READUPDATEX
(PSEUDO-$RCV,...
ANALYZE
REQUEST TYPE
^CHECKPOINT(2)
TAKEOVER :=
TRUE
^RECLAIMBUFFER
(@E^RCV^BUF, 10)
^WTX TERM
TAKEOVER?
WTRD
FALSE
^WTX TERM
TRUE
^REPLYX
WT
NORMAL
TAKEOVER
VST021.vsd