for each tQbuffers where tQbuffers.tiIsInUseBy <> 0: viBufferID = ?. viBufferID = tQbuffers.thBuffer:unique-id no-error. if viBufferID = tQbuffers.tiBufferID then do: tQbuffers.thBuffer:buffer-release(). tQbuffers.tiIsInUseBy = 0. end. else delete tQbuffers. end.