VMS Help TCPIP Services, TELNET, TN3270 Keyboard Functions, DV_CNCL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    VT100: EXT + U              VT200: EXT + Remove
    DEFINE_KEY Function: DVCNCL

    Cancels the RECORD function. Use the DV CNCL function if you
    begin using the RECORD function and then decide you want to stop.
    If you want to delete a sequence that has already been recorded
    on a PF key, use the RECORD function, press the PF key, and then
    use the DV CNCL function.