Library /sys$common/syshlp/dce$uaf_help.hlb ATTACH, Qualifiers, /IDENTIFICATION  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /IDENTIFICATION
       /NOIDENTIFICATION (default)

    Specifies the process identification (PID) of the process to
    which terminal control will be transferred. Leading zeros can
    be omitted. The /IDENTIFICATION qualifier is incompatible with
    the process-name argument.

    If you omit the /IDENTIFICATION qualifier, you must specify a
    process name.