CBFS Filter 2020 C++ Builder Edition

Questions / Feedback?

BeforeCanFileBeDeleted Event

Fires before the filesystem determines whether a file or directory can be deleted.

Syntax

typedef struct {
  String FileName;
  bool CanDelete;
  void* FileContext;
  void* HandleContext;
  bool ProcessRequest;
  int ResultCode;
} TcbfCBFilterBeforeCanFileBeDeletedEventParams;

typedef void __fastcall (__closure *TcbfCBFilterBeforeCanFileBeDeletedEvent)(System::TObject* Sender, TcbfCBFilterBeforeCanFileBeDeletedEventParams *e);

__property TcbfCBFilterBeforeCanFileBeDeletedEvent OnBeforeCanFileBeDeleted = { read=FOnBeforeCanFileBeDeleted, write=FOnBeforeCanFileBeDeleted };

Remarks

This event fires before the filesystem determines whether the file or directory specified by FileName can be deleted. Such determinations are made anytime the Windows API's NtSetInformationFile function is called with FILE_DISPOSITION_INFORMATION or FILE_DISPOSITION_INFORMATION_EX data (which occurs for both "normal" delete requests, and file create/open requests that include the FILE_FLAG_DELETE_ON_CLOSE flag).

Applications may handle the underlying request by setting CanDelete as desired and then setting ProcessRequest to false. If this event fired in response to a file being opened with the FILE_FLAG_DELETE_ON_CLOSE flag, then setting CanDelete to false will prevent the file from being opened in the first place.

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

The CanDelete parameter specifies whether the file or directory can be deleted.

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 specified file or directory was not opened before the request, both contexts will be absent, in which case these parameters will be NULL.)

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.

 
 
Copyright (c) 2020 Callback Technologies, Inc. - All rights reserved.
CBFS Filter 2020 C++ Builder Edition - Version 20.0 [Build 7543]