>>>On a network. Everyone has their own resource file that has their userid in the file name. Unfortunately I did not forsee that some users might attempt log onto the system more than once. For various security reasons, they are not allowed to do this. But my setting of the resource file to their useridresource file gets them multiple messageboxes. the useridresource file is already being used.
>>>
>>>How can I know that a file is already being used?
>
>>Generally, you may trap for an error opening any DBF file:
>>ON ERROR lErrorflag=.t.
>>USE mytable EXCL
>>ON ERROR
>>IF lErrorflag=.t.
>>*** do something here
>>ENDIF
>
>Good idea. I could use an on error for my "set resource" statement. Then I could assume that the error was that the file was already in use. I already have an error handler. It is not an ideal solution. Is not there someway I can just ask if a file is already open?

You can try to FOpen("mytable.dbf"), and it will return a zero (or -1?) if it can't open.

 lnFhandle=fopen("MyTable.dbf")
if lnFhandle>0
   * it's ok
else
   =messagebox("Get out first, then get in")
   quit
endif
=fclose(lnFhandle)