CBFS Filter 2020 Delphi Edition

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BeforeUnlockSingle Event

Fires before a particular locked byte range in a file is unlocked.


type TBeforeUnlockSingleEvent = procedure (
  Sender: TObject;
  const FileName: String;
  var Offset: Int64;
  var Length: Int64;
  Key: Int64;
  var FileContext: Pointer;
  var HandleContext: Pointer;
  var ProcessRequest: Boolean;
  var ResultCode: Integer
) of Object;

property OnBeforeUnlockSingle: TBeforeUnlockSingleEvent read FOnBeforeUnlockSingle write FOnBeforeUnlockSingle;


This event fires before a particular locked byte range in the file specified by FileName is unlocked.

Applications may use this event to modify the request's parameters.

Applications only need to handle this event if they've added a standard filter rule that includes the FS_CE_BEFORE_LOCK_CONTROL flag.

The Offset, Length, and Key parameters contain the starting byte offset, length, and key values (respectively) specified when the byte range was locked. Please refer to the BeforeLock event's documentation for more information.

The FileContext and HandleContext parameters are placeholders for application-defined data associated with the file and specific handle, respectively. Please refer to the Contexts topic for more information.

The ProcessRequest parameter controls whether the request is sent onwards for further processing by subsequent filter drivers and the filesystem; it is True by default.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource isn't available, security checks failed, etc.), set it to a non-zero value to report an appropriate error. Please refer to the Error Reporting and Handling topic for more information.

This event is fired synchronously; please refer to the Event Types topic for more information.

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CBFS Filter 2020 Delphi Edition - Version 20.0 [Build 8047]