/CHANGE_BAR[=([change-char][,[NO]NUMBER])]

    Marks differences using the specified character. The /CHANGE_BAR
    qualifier displays output that depends on where the qualifier is
    placed. The following examples describe the result of /CHANGE_BAR
    qualifier placement.

    The following placement displays the latest version of input.file
    with the pound sign (#)  preceding any lines that differ from the
    preceding version of input.file:

    $ DIFFERENCES input.file/CHANGE_BAR=#

    The following placement displays input.file;2 with the pound sign
    (#)  preceding any lines that differ from input.file;1:

    $ DIFFERENCES input.file;1  input.file;2 /CHANGE_BAR=#

    The following placement displays input.file;1 with the pound sign
    (#)  preceding any lines that differ from input.file;2:

    $ DIFFERENCES input.file;1/CHANGE_BAR=#  input.file;2

    The following placement displays input.file;1 with the percent
    sign (%)  preceding any lines that differ from input.file;2, and
    also displays input.file;2 with the pound sign (#)  preceding any
    lines that differ from input.file;1:

    $ DIFFERENCES input.file;1/CHANGE_BAR=% input.file;2/CHANGE_BAR=#

    o  If you do not specify a change bar character, the default is
       an exclamation point (!)  for ASCII output.

    o  If you specify hexadecimal or octal output (see the
       description of the /MODE qualifier), the change bar character
       is ignored and differences are marked by a "***CHANGE***"
       string in the record header. The keyword NONUMBER suppresses
       line numbers in the listing.

    o  If neither the NUMBER nor the NONUMBER keyword is specified,
       the default is controlled by the /[NO]NUMBER command
       qualifier.

    o  If you specify only one option, you can omit the parentheses.

    o  If you use an exclamation point (!)  as the specified
       character, you must enclose it in quotation marks (" ");  for
       example, /CHANGE_BAR=("!",NUMBER).