diff --git a/src/inc/taoserror.h b/src/inc/taoserror.h
index f153a9a5739ebbae5c84b4a36065776472aa8083..c598c56d15c6e7dbdf19425a7de7556d765ff56d 100644
--- a/src/inc/taoserror.h
+++ b/src/inc/taoserror.h
@@ -46,6 +46,7 @@ static STaosError errors[] = {
 #endif
 
 TAOS_DEFINE_ERROR(TSDB_CODE_ACTION_IN_PROGRESS,         0, 1, "action in progress")
+TAOS_DEFINE_ERROR(TSDB_CODE_MSG_NOT_PROCESSED,          0, 4, "message not processed")
 TAOS_DEFINE_ERROR(TSDB_CODE_LAST_SESSION_NOT_FINISHED,  0, 5, "last session not finished")
 TAOS_DEFINE_ERROR(TSDB_CODE_INVALID_SESSION_ID,         0, 6, "invalid session id")
 TAOS_DEFINE_ERROR(TSDB_CODE_INVALID_TRAN_ID,            0, 7, "invalid transaction id")
diff --git a/src/inc/trpc.h b/src/inc/trpc.h
index bde863522a5b7cd4b51b03eee9e8e2f634cdc97b..17deb33f37e31972fd3afffad6fccf5518230c00 100644
--- a/src/inc/trpc.h
+++ b/src/inc/trpc.h
@@ -43,7 +43,7 @@ typedef struct {
 } SRpcConnInfo;
 
 typedef struct {
-  char    msgType;
+  uint8_t msgType;
   void   *pCont;
   int     contLen;
   int32_t code;
diff --git a/src/rpc/inc/tqueue.h b/src/util/inc/tqueue.h
similarity index 100%
rename from src/rpc/inc/tqueue.h
rename to src/util/inc/tqueue.h
diff --git a/src/rpc/src/tqueue.c b/src/util/src/tqueue.c
similarity index 95%
rename from src/rpc/src/tqueue.c
rename to src/util/src/tqueue.c
index ab440d4819b359d6a140ae5d754c046df560fa7d..cb218126a877714c71ef2363960695fa4fb7694b 100644
--- a/src/rpc/src/tqueue.c
+++ b/src/util/src/tqueue.c
@@ -24,8 +24,8 @@ typedef struct _taos_qnode {
 } STaosQnode;
 
 typedef struct _taos_q {
-  int                 itemSize;
-  int                 numOfItems;
+  int32_t             itemSize;
+  int32_t             numOfItems;
   struct _taos_qnode *head;
   struct _taos_qnode *tail;
   struct _taos_q     *next;    // for queue set
@@ -37,15 +37,15 @@ typedef struct _taos_qset {
   STaosQueue        *head;
   STaosQueue        *current;
   pthread_mutex_t    mutex;
-  int                numOfQueues;
-  int                numOfItems;
+  int32_t            numOfQueues;
+  int32_t            numOfItems;
 } STaosQset;
 
 typedef struct _taos_qall {
   STaosQnode   *current;
   STaosQnode   *start;
-  int           itemSize;
-  int           numOfItems;
+  int32_t       itemSize;
+  int32_t       numOfItems;
 } STaosQall; 
   
 taos_queue taosOpenQueue(int itemSize) {
@@ -57,7 +57,7 @@ taos_queue taosOpenQueue(int itemSize) {
   }
 
   pthread_mutex_init(&queue->mutex, NULL);
-  queue->itemSize = itemSize;
+  queue->itemSize = (int32_t)itemSize;
 
   return queue;
 }
@@ -108,6 +108,8 @@ int taosWriteQitem(taos_queue param, void *item) {
   if (queue->qset) atomic_add_fetch_32(&queue->qset->numOfItems, 1);
 
   pthread_mutex_unlock(&queue->mutex);
+
+  return 0;
 }
 
 int taosReadQitem(taos_queue param, void *item) {
@@ -291,8 +293,9 @@ int taosReadQitemFromQset(taos_qset param, void *item) {
     if (qset->current == NULL) 
       qset->current = qset->head;   
     STaosQueue *queue = qset->current;
-    qset->current = queue->next;
+    if (queue) qset->current = queue->next;
     pthread_mutex_unlock(&qset->mutex);
+    if (queue == NULL) break;
 
     pthread_mutex_lock(&queue->mutex);
 
@@ -326,8 +329,9 @@ int taosReadAllQitemsFromQset(taos_qset param, taos_qall *res) {
     if (qset->current == NULL) 
       qset->current = qset->head;   
     queue = qset->current;
-    qset->current = queue->next;
+    if (queue) qset->current = queue->next;
     pthread_mutex_unlock(&qset->mutex);
+    if (queue == NULL) break;
 
     pthread_mutex_lock(&queue->mutex);