JetOSSnapshotTruncateLogInstance Function

Article
08/26/2021

Applies to: Windows | Windows Server

JetOSSnapshotTruncateLogInstance Function

The JetOSSnapshotTruncateLogInstance function truncates the log for a specified instance during a snapshot session.

Windows Vista: JetOSSnapshotTruncateLogInstance is introduced in Windows Vista.

    JET_ERR JET_API JetOSSnapshotTruncateLogInstance(
      __in          const JET_OSSNAPID snapId,
      __in          JET_INSTANCE instance,
      __in          const JET_GRBIT grbit
    );

Parameters

snapId

The identifier of the snapshot session.

instance

The instance that will be used for this call.

grbit

The options for this call. This parameter can have a combination of the following values.

grbit can be one of the following values:

Value	Meaning
JET_bitAllDatabasesSnapshot	All the databases are attached so the storage engine can compute and do the log truncation.
0 (zero)	No truncation will occur.

Return Value

This function returns the JET_ERR datatype with one of the following return codes. For more information about the possible ESE errors, see Extensible Storage Engine Errors and Error Handling Parameters.

Return code	Description
JET_errSuccess	The operation completed successfully.
JET_errInvalidGrbit	The grbit parameter is invalid.
JET_errOSSnapshotInvalidSequence	The snapshot session is not in the state in which a truncation can occur. Possible causes are: The call completes after the snapshot session timed out. The session was specified as a copy snapshot.

Return code

Description

JET_errSuccess

The operation completed successfully.

JET_errInvalidGrbit

The grbit parameter is invalid.

JET_errOSSnapshotInvalidSequence

The snapshot session is not in the state in which a truncation can occur. Possible causes are:

The call completes after the snapshot session timed out.
The session was specified as a copy snapshot.

If this function succeeds, the log files for one or all of the instances that are part of the snapshot session will be truncated, if possible.

Remarks

This function should be called only if the snapshot was created with the JET_bitContinueAfterThaw option. Otherwise, the snapshot session ends after the call to JetOSSnapshotThaw.

Requirements

Requirement	Value
Client	Requires Windows Vista.
Server	Requires Windows Server 2008.
Header	Declared in Esent.h.
Library	Use ESENT.lib.
DLL	Requires ESENT.dll.

JetOSSnapshotTruncateLogInstance Function