I use flock and unlock in these cases

>here is the code, if you need more let me know
>
>SELECT VO
>APPEND blank
do while not flock()
enddo
>replace nSequence WITH lnSeq
>replace npartid with lcPartid
>replace dtissuedate WITH DATE()
>IF !EMPTY(lcUserid)
> replace cIssuer WITH lcUserid
>ENDIF
>replace dValidfrom WITH ldValidFrom
>replace dValidTo WITH ldValidTo
>replace cPackage with lcPack
>replace nInstrument WITH i
>replace nMaxAmount WITH lnPay * 100
>replace nAmount WITH lnAmnt * 100
>replace cStatus WITH "I"
>replace bprovrd WITH lbOver
>replace dLastupdate WITH DATE()
>replace bupload WITH .T.
>replace cLastuser WITH lcuserid
>replace cPriority WITH lcPri
unlock