VMS Help DSR, DSR Commands, Change bar commands  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The bar commands control the insertion of vertical bars (|) at
    the beginning of lines of text. The bars (usually called change
    bars) are normally inserted to indicate where changes in text
    have occurred since the previous edition of a document. You can
    specify a character other than the default character (vertical
    bars) to indicate changes by using the /CHANGE_BAR qualifier to
    the RUNOFF command line.

    Formats

      .ENABLE BAR

      .DISABLE BAR

      .BEGIN BAR

      .END BAR

    Abreviated formats

      .EBB

      .DBB

      .BB

      .EB

1 - Default

    .DISABLE BAR - Operation of the change bar function is not
    initially enabled. By default, there are no change bars and text
    is not indented.

2 - .ENABLE BAR

    The .ENABLE BAR command shifts all text following it three spaces
    to the right to make room for the bars on the left. The width of
    the lines of actual text is not altered.

3 - .DISABLE BAR

    The .DISABLE BAR command disables the bar commands but does not
    shift the lines of text back to their original position.

4 - .BEGIN BAR

    The .BEGIN BAR command causes DSR to start inserting vertical
    bars at the beginning of lines.

5 - .END BAR

    The .END BAR command causes DSR to stop putting vertical bars at
    the beginning of lines.