<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"> </head> <body bgcolor="#ffffff" text="#000000"> Hello, Could somebody please analyze the piece of source code below. I'd like to send a message containing an array of structures using low-level API. The sent message shall be received in Qt.  For the test purposes the structure is a two-string structure, the array contains 10 entries. The receiver side (Qt) defines following parameter for the slot method (Q_DECLARE METATYPE are omitted here): structure {   QString str1;   QString str2; } twoString; typedef QVector<twoString> structArr; void slotMethod( structArr arr ); Now to the sender. I have to use low-level API :(. Running the example below I get the following run-time error: -------------------PASSED_0 -------------------PASSED_1 process 6585: Array or variant type requires that type struct be written, but begin_struct was written   D-Bus not built with -rdynamic so unable to print a backtrace And now the source code: gboolean arrayOfStructSignal( MyClass *self ) {   // unique number   dbus_uint32_t   serialNr = 0;   // DBusMessage   DBusMessage     *msg;   // Dbus Message Iterators - main, array, structure   DBusMessageIter iter,                   arr,                   strct;   // Connection   DBusConnection  *conn;   gchar buffer[BUFF_SIZE_SMALL];   const char *buff = buffer;   if( NULL == self )   {     return false;   }   conn = self->m_conn;   assert( NULL != conn );   // create a signal and check for errors   msg = dbus_message_new_signal( "/myObj",                                     "my.test.Interface",                                  "arrOfStructSignal" );   if (NULL == msg)   {     return false;   }   dbus_message_iter_init_append( msg, &iter );   // open the array of structures   dbus_message_iter_open_container( &iter,                                     DBUS_TYPE_ARRAY,                                     "r",                                     &arr );    cout << "-------------------PASSED_0 " <<  endl;   // array of 10 structures a(ss)  - for test   for( int i = 0; i < 10; i++ )   {     cout << "-------------------PASSED_1 " <<  endl;     // Open the a structure within an array      // Here run-time error  !!!!!!!!!!!!!!!!!!!     dbus_message_iter_open_container( &arr,                                       DBUS_TYPE_STRUCT,                                       NULL,                                       &strct );     cout << "-------------------PASSED_2 " <<  endl;     memset( buffer, 0, BUFF_SIZE_SMALL );     sprintf(buffer, "test 0 %d", i );     // append first string to the structure     if( !dbus_message_iter_append_basic(&strct, DBUS_TYPE_STRING, &buff) )     {       dbus_message_unref(msg);       return false;     }     cout << "-------------------PASSED_3 " <<  endl;     memset( buffer, 0, BUFF_SIZE_SMALL );     sprintf(buffer, "test 0 %d", i );     // append second string to the structure     if( !dbus_message_iter_append_basic(&strct, DBUS_TYPE_STRING, &buff) )     {       dbus_message_unref(msg);       return false;     }     cout << "-------------------PASSED_4 " <<  endl;     // close structure container     dbus_message_iter_close_container( &arr, &strct );   }   // close struct container   dbus_message_iter_close_container( &iter, &arr );   // send the message and flush the connection   if( !dbus_connection_send(conn, msg, &serialNr))   {     dbus_message_unref(msg);     return false;   }   dbus_connection_flush(conn);      // free the message   dbus_message_unref(msg);      return true; } Thanks for your help regards, Bogdan </body> </html>