Starts an asynchronous eject on a mountable.
When this operation has completed, callback will be called with
user_user data, and the operation can be finalized with
gio.file.File.ejectMountableFinish.
If cancellable is not null, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation
was cancelled, the error gio.types.IOErrorEnum.Cancelled will be returned.
Starts an asynchronous eject on a mountable. When this operation has completed, callback will be called with user_user data, and the operation can be finalized with gio.file.File.ejectMountableFinish.
If cancellable is not null, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error gio.types.IOErrorEnum.Cancelled will be returned.