LogRecordSequence.BeginWriteRestartArea Method (ArraySegment<Byte>, SequenceNumber, ReservationCollection, AsyncCallback, Object)


Begins an asynchronous restart area write operation, using space previously reserved in the sequence. This method cannot be inherited.

Namespace:   System.IO.Log
Assembly:  System.IO.Log (in System.IO.Log.dll)

public IAsyncResult BeginWriteRestartArea(
	ArraySegment<byte> data,
	SequenceNumber newBaseSeqNum,
	ReservationCollection reservation,
	AsyncCallback callback,
	object state


Type: System.ArraySegment<Byte>

Byte array segments that will be concatenated and appended as the record.

Type: System.IO.Log.SequenceNumber

The new base sequence number. The specified sequence number must be greater than or equal to the current base sequence number.

Type: System.IO.Log.ReservationCollection

A ReservationCollection that contains the reservation that should be used for this restart area.

Type: System.AsyncCallback

An optional asynchronous callback, to be called when the restart area write is complete.

Type: System.Object

A user-provided object that distinguishes this particular asynchronous restart area write request from other requests.

Return Value

Type: System.IAsyncResult

An IAsyncResult that represents the asynchronous restart area write operation, which could still be pending.

Exception Condition

newBaseSeqNum is not valid for this sequence.


The specified log enumeration start sequence number is invalid.


data cannot be appended because it is larger than the maximum record size.


reservation was not created by this record sequence.


One or more of the parameters is null.


A new or existing archive tail or base of the active log is invalid.


newBaseSeqNum is not between the base and last sequence numbers of this sequence.


The request could not be performed because of an unexpected I/O exception.


The request could not be performed because of an I/O device error.


The method was called after the sequence has been disposed of.


There is not enough memory to continue the execution of the program.


Access for the specified log sequence is denied by the operating system.


The record sequence is full.

You should pass the IAsyncResult returned by this method to the EndWriteRestartArea method to ensure that the restart area write operation has completed and resources can be freed appropriately. If an error has occurred during an asynchronous restart area write operation, an exception is not thrown until the EndWriteRestartArea method is called with the IAsyncResult returned by this method.

Data contained in the data parameter will be concatenated into a single byte array for appending as the record. However, no provision is made for splitting data back into array segments when the record is read.

When the operation successfully completes, the base sequence number has been updated. All log records with sequence numbers less than the new base sequence number are inaccessible.

If a ReservationCollection is specified, the written restart area will consume space that has been previously reserved, using a reservation contained in the collection. If the method succeeds, it will consume the smallest reservation that can hold the data, and that reservation will be removed from the collection.

If a record sequence has been disposed of, or if you pass an invalid argument, exceptions are thrown immediately within this operation. Errors that occurred during an asynchronous append request, for example, a disk failure during the I/O request, will result in exceptions being thrown when the EndWriteRestartArea method is called.

.NET Framework
Available since 3.0
Return to top