How can I programmatically create and use a global variable?

I have an app where the number of AI DAQmx tasks I create are specified in a config file. I have a monitor task that periodically looks at the latest values from all DAQ tasks. I've been doing this with a set of global variables because it was the simplest way to do it. But to do this, I have to explicitly create a separate AI task that uses the hard-coded global variable name for the DAQmx samples. I would prefer to only write one VI for the DAQ loop that writes to a global variable that I programmatically create based on the config file. The only solution I can think of is to use a global variable "pool" that is sized bigger than I expect to need, and then have a big switch case to select which one I want based on the task index. But this sounds pretty silly.

I tend to agree with Ben. I don't buy the concept of taking the asy way out (globals) because it very rarely will things remain static. You almost always have to extend the features and functionality of an application and then you will run into issues with sloppy and lazy implementations. The solutions offered may require a little time to learn but once you do it doesn't really require any extra effort.
Mark Yedinak
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Wreck of the Edmund Fitzgerald - Gordon Lightfoot

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I am trying to create a program that opens several front panels (sub-VI's) in sequence. in each front panel, the user would open a file that the name is obtained from the previous sub-VI. I would like to know how i could pass the filename and refnum of the file thorough from one sub-vi to another. A global variable would do it in VB, but how do we do global vars in LABWIEW. thanks
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Chances are if you have seen VI in the forest it hasn't fallen.
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Passing Refnum.zip ‏21 KB

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How can I programmatically create and use a global variable?

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