{BOUnds | BNDs}  [ ? | [ col1 [ col2 ] [ EXT ] ] ]

            -Set margin boundary
             Boundary setting influence Find/Change/Sort/Split/Tflow commands and
             Shift(<,>,(,),[,])/Paste(o,p,n)/Compare(=)/CaseConversion(u,_)/Tflow(TF,:,;) line commands.
            -Set default for the directory when entered on directory list panel.
            -Use INI command(write to ini file) to keep setting for the next session.

            ?        :display help message
            col1/col2:left and right boundary column
                      "0" means reset, "*" means keep current value.
                      Reset both side if operand missing.
            EXT      :set defalt for the file with same extension name as the file opened now.