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 G_IO_ERROR_CANCELLED will be returned.
When the operation is finished, callback will be called.
You can then call g_file_unmount_mountable_finish() to get
the result of the operation.
Unmounts a file of type G_FILE_TYPE_MOUNTABLE
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 G_IO_ERROR_CANCELLED will be returned.
When the operation is finished, callback will be called. You can then call g_file_unmount_mountable_finish() to get the result of the operation.