Syntax:  SET BUFFER RIGHT MARGIN column

  Sets the right margin for the current buffer.

  LSE sets the buffer's right margin to column 80, by default, or to
  the column number you specify.  If the SET BUFFER WRAP command is on,
  this command affects the FILL and ENTER SPACE commands.

  RELATED COMMANDS:

     ENTER SPACE                 SET BUFFER WRAP
     FILL                        SHOW BUFFER
     SET BUFFER LEFT MARGIN