CBFS Filter 2020 Delphi Edition

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AfterSetAllocationSize Event

Fires after a file's allocation size is changed.


type TAfterSetAllocationSizeEvent = procedure (
  Sender: TObject;
  const FileName: String;
  AllocationSize: Int64;
  var Status: Integer;
  var FileContext: Pointer;
  var HandleContext: Pointer;
  var ResultCode: Integer
) of Object;

property OnAfterSetAllocationSize: TAfterSetAllocationSizeEvent read FOnAfterSetAllocationSize write FOnAfterSetAllocationSize;


This event fires after the allocation size of the file specified by FileName is changed.

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

The AllocationSize parameter reflects the new allocation size, in bytes. A file's allocation size is typically larger than its actual size since filesystem operations often reserve space on disk before writing additional data to a file.

The Status parameter contains an NT status code that indicates the outcome of the operation; 0 indicates success. To convert this value to a Win32 error code, call the NtStatusToWin32Error method. Please note that this event won't fire for failed requests unless the ProcessFailedRequests property is enabled. Applications may change this parameter's value if they want a different NT status code to be returned.

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. (If the system's cache manager or memory manager initiated the operation, HandleContext may be absent, in which case it will be nil.)

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]