If you design the processes so that they access the record for input with no locks then the problem doesn’t exist. That would mean using READ(N) or CHAIN(N) ( N for no lock).
Displaying the screen, waiting for a change without the record locked.
When the program receives the changed screen to proceess would:
1. Access record and lock it
2. Check record to insure that it hasn’t been updated by another user
3. Update it.
The lock last’s very short time, less than the file time out limit.
If, at step 2, the file has changed, don’t update it — show the new data and a messaage that it was changed and allow the user to change it again.
With or without the above change, inquiry mode which should access the record with an F-Spec of input rather than update shouldn’t encounter a locked record.