Generally LIS code and error message also important for error handling. Error code may be used for `switch` statement and a message for log description for humans. Here examples of LIS error messages *from RFC* ```xml <?xml version="1.0"?> <error xmlns="urn:ietf:params:xml:ns:geopriv:held" code="locationUnknown"> <message xml:lang="en">Unable to determine location </message> </error> ``` my use case ```xml <?xml version="1.0" encoding="UTF-8"?> <urn:error xmlns:urn="urn:ietf:params:xml:ns:geopriv:held" code="generalLisError"> urn:messageAn unspecified error occurred while handling LocationRequest.</urn:message> </urn:error> ``` So I can use a `switch` statement like ``` if ($var(res) == 200 && $var(res) > 203 ) { switch $(varLisErrorCode) { case "locationUnknown": xlog(L_ERR, "Received LIS error response: $(varLisErrorMessage)"); route(TRY_DEFAULT_PSAP); case "generalLisError": xlog(L_ERR, "Received unexpected LIS error response: $(varLisErrorMessage)"); route(TRY_OTHER_LOCATION_METHOD); default: } } ``` For me more preferable to define module param `xavp_responce` ``` modparam("lost", "xavp_responce", "held_responce") ``` If `xavp_responce` defined then set keys. 1) HTTP_ERROR_CODE; 2) HELD_ERROR_CODE; 3) HELD_ERROR_MESSAGE.