There's a direct relation between table lock and FOR clauses (SET LOCK also involved). See my answer to Shawn for more details.

Vlad

>But AFAIK, FOR clause doesn't affect on file or records locking.
>
>Have a happy day
>Vladimir Shevchenko
>
>> We are experiencing network related error messages as more and more users
>
>> use our app. The error messages are: "Attempting To Lock..." and "Record
>
>> Not Available, Please Wait..."
>>
>> I was told that one way to minimize such errors was to avoid FOR clauses
>> whenever possible.
>>
>> I was told that FoxPro places a lock on a table when using a FOR clause
>in
>> order to prevent values from changing during the FOR clause operation.
>>
>> I tried to test to see if this was happening. When I ran the tests, I
>found
>> no evidence that a table lock was being placed.