[libvirt] Add a new api, get this error.gnutls_record_recv: A TLS packet with unexpected length was received.

hi all, Sorry to disturb you. I wanna to add a new api to get some sheepdog cluster info, but I has get this error, I don't know how to do. I have add a function to daemon/remote.c that call the libvirt.c 's api, remoteDispatchConnectExecuteCommand, and here i get the return value. struct remote_connect_execute_command_ret { remote_nonnull_string ret_val; }; typedef struct remote_connect_execute_command_ret remote_connect_execute_command_ret; static int remoteDispatchConnectExecuteCommand (struct qemud_server *server ATTRIBUTE_UNUSED, struct qemud_client *client ATTRIBUTE_UNUSED, virConnectPtr conn, remote_message_header *hdr ATTRIBUTE_UNUSED, remote_error *rerr, remote_connect_execute_command_args *args, remote_connect_execute_command_ret *ret) the return value has been in ret->ret_val. I know the func remoteDispatchDomainDumpXml returns it's values by ret->xml. And after this, the things is the same, but when I dump xml, it's ok, but when i wanna to get my value, it's cause this error: error : qemudClientReadBuf:1708 : gnutls_record_recv: A TLS packet with unexpected length was received. Could any body tell me, if I wanna to get a string data, do I need to do any additional actions?