Bugs in EDLIN v3.30

    ■   The /B argument is not recognized if entered as /b (in lowercase).
        This switch is used when editing files with embedded Ctrl-Z char-
        acters.

    ■   It is possible to load, edit, and save a .BAK file if the .BAK
        file extension is entered (partly or entirely) in lowercase (.bak).

        Other versions correctly issue an error message in this case.