Sharing a Queue between Two VIs in the Same LabVIEW Project

[Jupiter02]

Overview

This example demonstrates how a queue can be shared by multiple VIs in the same LabVIEW Project. 

Description

The first VI, Enqueue.vi, obtains a queue called myQueue and enqueues integers 0 to 1 in a for loop. The second VI, Dequeue.vi, dequeues each element from myQueue and displays the result in an Array. The purpose of this is to demonstrate how, in a LabVIEW project, you can share a queue across VIs by writing the same queue name in the Obtain Queue function.

Steps to Implement or Execute Code

1. In order to run this example, save the Zip File attached
2. Open the project Queue.lvproj
3. Open both the Enqueue and Dequeue VIs
4. Run Dequeue.vi and Enqueue.vi
5. Notice how the Array Indicator in Dequeue.vi is populated with the values which were enqueued in Enqueue.vi

Requirements

Software

LabVIEW 2011 or later

Block Diagram

[Larry.C]

Hi,

It is generally good practise to release the queue reference in both VIs. The reason you have a "force destroy" terminal is that releasing the queue does not destroy it if another queue reference is still live.

By doing this you avoid memory leaks if this method is used in your application in various places being ran sporadically.

Another nice way of doing this is sharing a queue reference wire using an FGV. This allows you to make descrete wrappers for your messagin system (much less spaghetti).

[crossrulz]

Here's a link to an example of using the Action Engine to hold the queue reference and then you just have to call the Action Engine to send your information.  I do this for almost every system I make.

https://decibel.ni.com/content/docs/DOC-37042