STM vs shared variable

Question

From what I have seen on the forum so far, it seems to me that compared to shared variable, STM is better with different data type and bigger data size. The only thing that makes shared variable slightly better than STM is being a bit more simple.  If that's the case, why use shared variable at all?  Are there aplication where shared variable is a lot better than STM?  
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Answer 1

soupy wrote:
Yup, you can set up multiple connections with STM, but it does not come with the stock examples. You'll have to do quite a bit of development to make it happen. This is the implementation i plan to go with, and the work involved is what is preventing me from going this direction.
Getting off-topic a bit from the original question here, but I wrote a server in LabVIEW that used the TCP primitives and handled multiple connections.  The same approach should work for the STM, using STM connection info clusters in place of connection references.  In case it's of use to you, here's what I did (unfortunately I no longer have access to that code, it was several jobs ago):
- have one loop dedicated to listening for new connections.  When one arrives, put it in a queue and go back to listening.
- in another loop, maintain an array of connection ids.  For each connection ID, also store a timestamp.  When a new connection arrives, dequeue it, bundle it with the current time, and add it to the connection ID array.
- inside the same loop, add another loop to iterate through each connection, checking for data.  If there's data, do whatever you need to with it (usually enqueue it for some other loop to handle), and update the timestamp associated with that connection ID.  Ignore error 56 (timeout) since any connection that doesn't have data will report this error.  For any error that indicates the connection is closed or no longer available, remove that connection from the array.  If the difference between the timestamp for a connection and the current time is greater than some amount, close the connection and remove it from the array (this is optional, but prevents you from leaving connections open that haven't been cleanly closed).
If you're using a command-response scheme, and you pass the data off to another loop to handle, you'll need to track the connection with which it is associated so that the response can be sent to the right place.  I was using "Variant to Flattened String" and "Flattened String to Variant" for data passing over TCP, so I just tacked on the connection information as a variant attribute, but there are many other ways to handle this.