jacktby@xxxxxxxxx -------------- here is the codes for pg16. static relopt_string stringRelOpts[] = { /* list terminator */ {{NULL}} }; And I add my string type arguments here, it can't work well. When I debug, it comes to func allocateReloptStruct, at the code line "size += optstr->fill_cb(val, NULL);", it gives me segment fault. what else do I need to add? can you give me an example?