To check if the certain table is opened in the particular DS you need to use aUsed() function.

I'm missing something... why not just the USED() function? The only problem I see is if the table could have some other alias, meaning USED() and aUSED() won't spot it.

USE mytable ALIAS someother
? USED('mytable') &&returns .F.
=aUSED(aTables)
? aTables(1,1) &&returns SOMEOTHER, not mytable

Then you'd need to use the DBF() function to iterate through looking for an alias with the correct underlying table. Seems like a lot of work.

How about

Local llMyAliasOpen
Select 0
llMyAliasOpen=.F.
Try
	Use mytable Again Alias myalias
Catch
	*---myalias is open now one way or another...
	*---flag this so it doesn't get closed at end of routine
	llMyAliasOpen=.T.
Finally

You have to use ALIAS or it will reopen the table with A, B. C... aliases. You can open it ALIAS mytable if you want to use the tablename. It would be much more complex if you want to use any existing alias for that table that may happen to be open, but that's time for a redesign IMHO.