 --- Known Bugs
     o [SET] ARBCHAR accepts the multiple matches argument but it is
       not implemented in target searches.
     o MOVE BLOCK when the marked block is in a different file to
       the current file results in deletion of 1 line fewer from
       the source file. Cursor can also be left below the Bottom of File
       marker.
     o DUPLICATE BLOCK when issued with a portion of the marked block
       not being displayed on the bottom of the screen can result in the
       cursor being moved to the current line rather than the screen
       scrolling.
     o move block when the target line is the last line of the screen
       causes the cursor to be positioned incorrectly
     o behaviour of prefix commands does not match XEDIT behaviour
     o VERSHIFT RIGHT does not stop when it gets to the end of the zone.
     o prefix synonyms can be parsed illegally in certain circumstances.
       eg.              SET PREFIX SYNONYM r "
           followed by: SET PREFIX SYNONYM rr ""
       When 'rr' is entered in prefix are, an invalid prefix macro is
       displayed. A workaround is available; reverse the order of the
       SET commands.
     o When in XEDIT compatibility mode, attempts to paste (via external
       methods) more than 1 line into the file area results in the first
       line being correctly added, but subsequent lines are executed as
       commands on the command line.
     o in AIX version, DEFINEing ENTER has no effect.
     o Resizing window in X11 version does not reposition cursor on
       focus line correctly or handle column not now in view.
       This also can happen after SCREEN 2. This happens under some
       circumstances, not all.
     o reduce the overhead of refreshing the 2nd view of the same file
       while in split screen mode.  Only refresh when something has
       changed!
     o Resizing X11 window while in SHOWKEY, causes screen to go black.
     o Running a prefix macro while in COMPAT XEDIT, results in
       "Error 0041: Invalid SOS command: ...."
     o MARK STREAM is incomplete.  Trying to COPY, MOVE or DELETE a
       stream block will NOT WORK!
     o any command that has a target as the last argument to that
       command will ignore trailing spaces in any string target.
       ie. ALL /fred   <== assume this has a trailing space
       The string "fred" will be searched for, not "fred ". To work
       around this, always delimit string targets.
       ie. ALL /fred /
       This will look for "fred ".

todo (-) or done (*) not in any particular order
     * finish QUERY/EXTRACT RING
     - support multiple arbchar matches in all string targets and in
       change command - memfind to return length of string found
     * bug when 2 screens displayed, one file, and a macro with 'qq'
       and 'x a.a' is executed. The first screen has a.a displayed,the
       second screen points to junk and crashes. Need to support an
       edit of one file to be displayed in both screens.
     - bug in move block from one file to another. removes 1 line less
       from source file than it should. also cursor position of source
       file can be left below the last line of the file.
     - bug with 'duplicate block' when block is on the bottom of screen;
       current line gets contents of block
     - add EXTRACT /FOCUS/ - maybe
     - COPY and MOVE commands to be consistent (add targets to MOVE)
     * support READV CMDLINE option
     - NEXTWINDOW command to clean up before it switches to another
       view when screen is split.
     - Have [SET] KEYBIND command.?
     - Provide REXX support under DOS with interface to Personal REXX.
     - Add REPEAT command
     - Add [SET] RANge
     - Still some cursor positioning bugs with prefix block deletes.
     - Add synonyms for commands
     - Printing with OS/2 version still doesn't work correctly.
     - Use Instore option on RexxStart() to execute in-memory macros
       eg. "define ENTER if command() Then 'sos execute'; Else
            Do 'cursor cmdline';'sos doprefix'; End"
     - add COMPRESS command (opposite of EXPAND)
     - improve performance when editing large files. some improvements,
       more to be done
     * add FIND, NFIND, FINDUP and NFINDUP commands.
     - add CLOCATE and CDELETE.
     - add [SET] WRAP and [SET] STREAM commands.
     - add PRESERVE and RESTORE commands.
     * change JOIN and SPLIT commands to work from command line and
       operate on current column position.
     - allow for optional highlighting of the current line for systems
       that cannot distinguish ANY highlighting by using something like
       >>>>34 in prefix area on line 34.
     * add QUERY SCREEN
