Merge pull request #5567 from taosdata/hotfix/TD-3464

[TD-3464]fix asyncdemo crash issue

tests/examples/c/asyncdemo.c

@@ -163,6 +163,16 @@ int main(int argc, char *argv[])
 
   getchar();
 
+  while(1) {
+    if (tablesProcessed < numOfTables) {
+       printf("wait for process finished\n");
+       sleep(1);
+       continue;
+    }  
+
+    break;
+  }
+
   taos_close(taos);
   free(tableList);