pg_result_status() returns status of result resource. Possible return values are PGSQL_EMPTY_QUERY, PGSQL_COMMAND_OK, PGSQL_TUPLES_OK, PGSQL_COPY_TO, PGSQL_COPY_FROM, PGSQL_BAD_RESPONSE, PGSQL_NONFATAL_ERROR and PGSQL_FATAL_ERROR.
See also pg_connection_status().