/BEFORE[=time]
       /NOBEFORE

    Selects only those files dated prior to the specified time. You
    can specify time as absolute time, as a combination of absolute
    and delta times, or as one of the following keywords: BOOT,
    LOGIN, TODAY (default), TOMORROW, or YESTERDAY. Specify one of
    the following qualifiers with the /BEFORE qualifier to indicate
    the time attribute to be used as the basis for selection:
    /BACKUP, /CREATED (default), /EXPIRED, or /MODIFIED.

    For complete information on specifying time values, see the
    OpenVMS User's Manual or the online help topic Date.