How do I open my table exclusively and pack my table?

>You application may have separate 'maintenance' module where data will be open >exclusively and you will give a user options to PACK, REINDEX, VALIDATE, etc.

I might need these options later on as well. Please help.

DELETE FROM testdata ;
WHERE testdata.serialnum = m.lcSerialNum AND ;
	testdata.testdatewrk = m.ldDateWrk

* I am not sure about this. I get File in use program error...	
USE testdata EXCLUSIVE
PACK testdata

Thanks,
Sam