Setting the path to the empty list restores the default path defined for the X server. There is only one search path per X server, not one per client. The encoding and interpretation of the strings is implementation dependent, but typically they specify directories or font servers to be searched in the order listed. However, when the font path is changed, the X server is guaranteed to flush all cached information about fonts for which there currently are no explicit resource IDs allocated. The meaning of an error from this request is implementation dependent.
Some numeric value falls outside the range of values accepted by the request.
Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error.