An application managing a target log stream can monitor the offloads
occurring on the source log stream via ENF event 48 writer offload
completion events as an indication of when there will be more data
to import (IXGIMPRT) to the target log stream. But the application
must also check the safe import point of the source
log stream. The application can do this in one of two ways:
- Listen for ENF event 48, notifying them of a change to the safe
import point (field IXGENFWrOffLoadSafeImportPoint in the parameter
list mapped by macro IXGENF contains the latest safe import point).
- Issuing the IXGQUERY service (see The safe import point: Using IXGQUERY and IXGIMPRT together) to verify
that the data is safe to import to the target log stream.
You must verify the safe import point because it is not always
updated for an IXGOFFLD initiated offload even though the safe import
point is tied to offloading. This is true because of the way system
logger manages log data set control intervals that are not yet full.