Currently, seekExact on a record store in WiredTiger has the following behavior:
After the first call to seekExact(), a call to next() will repeat the same answer (either eof or the record that was seek'd).
However, I found code (currently unused) that seems to assume that calling next() after seekExact() will have normal cursor semantics and actually return the next record after the one that was seek'd. I could find no comments or tests that lock in one behavior or the other. We should make it clear what the behavior should be for all storage engines.