[net.micro.pc] How to tell if BASIC is running?

reb2@ihlpa.UUCP (Brown) (07/18/86)

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I am writing a resident routine that will need to know
when BASIC is in control/running and when it is not.
Does anyone know of some flag that gets set when BASIC is
invoked or any other way to tell if BASIC is currently up?

Many thanks.

Rick Brown