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Shared variable 1:N

Hello,
 
I have a two questions about the shared variables. Previousy, I try to set in context my developing application.

I want to have a one server with bidirectional connection with N clients. Clients will be in different computers. These clients will be the user interface of server, that it execute the different actions. The idea is create remote actions in server and check and monitorice it in the clients.

Server will have all shared variables and will send information to the clients. However if any client change a parameter, the other clients must has change also.

Example: Any client selects the setup for execute the test cases.
For do that, is necessary that the first step of clients is introduce server ip address.

The questions are:

1- Is possible that clients has an event structure that check if server has changed any value of any shared variables ?

My idea is set a loop that read all time if variable change. But I think these method is not efficient, because I need a loop for every shared variable....

2- Is possible that server change properties of shared variables?  The idea is that server set invisible a control of a client for example. If it occurs the control of another clients also wil set to invisible

Aimar Roura

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IIRC\AFAIK, to get events on shared variables, the DSC is required. See Creating a Value Change Event for Shared Variables

 

Or this idea: Do away with DSC run-time license for getting shared variable value change events.

 

There are no build in properties to show or hide controls. Typically, you'd communicate that with another shared variable for each property (or a cluster containing them all).

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wiebe@CARYA wrote:

 

Or this idea: Do away with DSC run-time license for getting shared variable value change events.

 


I assume this is still the case? 3 years of LV seems like a weekend so i guess they've not discussed it yet. 😄

/Y

G# - Award winning reference based OOP for LV, for free! - Qestit VIPM GitHub

Qestit Systems
Certified-LabVIEW-Developer
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@Yamaeda wrote:

wiebe@CARYA wrote:

 

Or this idea: Do away with DSC run-time license for getting shared variable value change events.

 


I assume this is still the case? 3 years of LV seems like a weekend so i guess they've not discussed it yet. 😄

/Y


I think (from what I read in another thread) is that the CVI implementation will also poll. The DSC implementation might do this as well, it probably uses the CVI dll. This dll is open and described (for instance cvicnvcreatesubscriber). This dll needs callback function pointers, so it would require a LabVIEW dll and LoadLibrary\GetProcAddress, IIRC to provide those functions.

 

If that function also polls the variables, we might do the polling in LabVIEW...

 

EDIT: BTW that does mean it's not strange that this is not simply included in LabVIEW...

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