CBFS Filter 2020 Python Edition

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on_notify_filter_attach_to_volume Event

Fires when the filter has been attached to a newly-mounted filesystem volume.

Syntax

class CBFilterNotifyFilterAttachToVolumeEventParams(object):
  @property
  def volume_name() -> str: ...
  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

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

Remarks

This event fires when the filter has been attached to the newly-mounted filesystem volume specified by VolumeName. Please refer to the fire_volume_events property for more information.

Applications only need to handle this event if the fire_volume_events property includes the FS_MOUNT_NOTIFY flag. Please note that this event won't fire for any volumes skipped during the on_before_filter_attach_to_volume event; please refer to its documentation for more information.

Applications that use volume-specific rules should typically add such rules during the on_after_filter_attach_to_volume event, which is fired synchronously, rather than this one.

The format of the VolumeName parameter's value depends on whether the ResolveNtDeviceToDriveLetter configuration setting is enabled; please refer to its documentation for more information. Applications can obtain additional information about a volume by retrieving its GUID using the get_volume_guid method, and then using that GUID to call various Windows API functions.

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, set it to a non-zero value to report an appropriate error. Note, however, that this event fires after the operation has already completed, so reporting an error won't actually affect the operation itself. Please refer to the Error Reporting and Handling topic for more information.

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

Applications must be aware that this event fires as a direct response to a filesystem state change (mount or unmount). Various system components or third-party actors are able to perform supplementary filesystem mounting and unmounting during main unmount operations (Volume Service is one of such components). This can cause seemingly excessive events to be fired, and sometimes they can even be fired out of order (such as two *Attach or *Detach events fired in a row).

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CBFS Filter 2020 Python Edition - Version 20.0 [Build 8317]