CBFS Filter 2020 Python Edition

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on_after_lock Event

Fires after a range of bytes in a file is locked.

Syntax

class CBFilterAfterLockEventParams(object):
  @property
  def file_name() -> str: ...
  @property
  def offset() -> int: ...
  @property
  def length() -> int: ...
  @property
  def key() -> int: ...
  @property
  def fail_immediately() -> bool: ...
  @property
  def exclusive_lock() -> bool: ...
  @property
  def status() -> int: ...
  @status.setter
  def status(value) -> None: ...
  @property
  def file_context() -> int: ...
  @file_context.setter
  def file_context(value) -> None: ...
  @property
  def handle_context() -> int: ...
  @handle_context.setter
  def handle_context(value) -> None: ...
  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBFilter:
@property
def on_after_lock() -> Callable[[CBFilterAfterLockEventParams], None]: ...
@on_after_lock.setter
def on_after_lock(event_hook: Callable[[CBFilterAfterLockEventParams], None]) -> None: ...

Remarks

This event fires after a range of bytes in the file specified by FileName is locked; either by the OS, or on behalf of a user mode application that called the Windows API's LockFile or LockFileEx function.

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

The Offset parameter reflects the byte offset where the byte range lock starts.

The Length parameter reflects the length of the byte range lock.

The Key parameter reflects the key that the byte range lock is associated with. This key is used to identify the byte range lock in later unlock-by-key requests.

The FailImmediately parameter indicates whether the request was to fail if the lock could not be granted immediately.

The ExclusiveLock parameter indicates whether the byte range lock was to be exclusive (True) or shared (False).

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 nt_status_to_win_32_error method. Please note that this event won't fire for failed requests unless the process_failed_requests 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.

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 Python Edition - Version 20.0 [Build 8317]