Using a global for device handle

I am wondering if it is a good or bad practice (or perhaps doesn't matter) to keep the handle of an open device as a global variable. See image below for example:
www.vartortech.com

Enrique wrote:
GerdW wrote:
No, the comments go to "your approach may work, but using alternatives might reduce errors..."
"may work"... What problems I might face?
People randomly closing your task and not updating the task...
Multiple people trying to muck with the device at the same time (race condition)...
Please, learn from our experience. Do not go the route of using a global to hold your task. You will be much better off if you contain your drivers using an Action Engine or a Singleton.
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Using a global for device handle

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