VMS Help SET, HOST, /LAT, Qualifiers, /BREAK  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /BREAK=break-character

    Defines a character that generates a break on lines that expect a
    break rather than a carriage return. To generate a break, press
    the Ctrl and break-character keys together. The default break-
    character value is the tilde (~).

    You can select any ASCII character between @ and Z, except C, M,
    Q, S, Y, and the left bracket ([).  You cannot select a character
    that is already defined as the disconnect character.