Description

Read the fingerprint store from file on disk into the given ustate.

add_app_data_callback(data=data, context=the_new_context), is called for each ConnContext so created to let the application add app_data.

The tuple containing the add_app_data_callback function and the the data is optional, default is not to use app_data.

If an error occures, it raises an Exception with the attributes errno (containing a numeric gcry error code), os_errno (containing an OS errno, if possible) and strerror (containing a string describing the error)