There's no function that does this. Even if there were, it wouldn't be safe to check whether the table was used exclusively then open it if it weren't because another user could open it exclusively between the time you checked and the time you opened it.

The thing to do is to try to open the file and trap the error if it's open exclusively. Something like this:

lnError=0
ON ERROR lnError=ERROR()
USE mytable
IF lnError=1705 && File access denied
  =MESSAGEBOX('Could not open mytable')
  RETURN
ENDIF

>What function returns .t. if the table is already open exclusive. I
>need that for multiuser environment.
>thank's in advance