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SQL Anywhere 10.0.1 » QAnywhere » Writing QAnywhere Client Applications » Receiving QAnywhere messages

Receiving messages synchronously

To receive messages synchronously, your application explicitly polls the queue for messages. It may poll the queue periodically, or when a user initiates a particular action such as clicking a Refresh button.

To receive messages synchronously (.NET)

Declare message objects to hold the incoming messages.
```
QAMessage msg;
QATextMessage text_msg;
```

Poll the message queue, collecting messages:

if(mgr.start())  {
  for(;;) {
    msg = mgr.GetMessageNoWait("queue-name");
    if( msg == null ) {
      break;
    }
    addMessage( msg );
  }
  mgr.stop();
}

See GetMessageNoWait method.

To receive messages synchronously (C++)

Declare message objects to hold the incoming messages.
```
QAMessage * msg;
QATextMessage * text_msg;
```

Poll the message queue, collecting messages:

if( mgr->start() ) {
  for( ;; ) {
    msg = mgr->getMessageNoWait( "queue-name" );
    if( msg == NULL ) {
      break;
    }
    addMessage(msg);
  }
  mgr->stop();
}

See getMessageNoWait function.

To receive messages synchronously (Java)

Declare message objects to hold the incoming messages.
```
QAMessage msg;
QATextMessage text_message;
```

Poll the message queue, collecting messages:

if(mgr.start()) {
  for ( ;; ) {
    msg = mgr.getMessageNoWait("queue-name");
    if ( msg == null ) {
      break;
    }
    addMessage(msg);
  }
  mgr.stop();
}

See getMessageNoWait method.

To receive messages synchronously (SQL)

Declare an object to hold the message ID.
```
begin
    declare @msgid varchar(128);
```

Poll the message queue, collecting messages.

    loop
        set @msgid = ml_qa_getmessagenowait( 'myaddress' );
        if @msgid is null then leave end if;
        message 'a message with content ' || ml_qa_gettextcontent( @msgid ) || ' has been received';
    end loop;
    commit;
end

See: