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

       /IDENTIFICATION=pid

    Requires GROUP or WORLD privilege for processes other than your
    own.

    Specifies the process identification (PID) value of the
    kernel thread for which characteristics are to be changed. The
    /IDENTIFICATION qualifier overrides the process-name parameter.

    The PID is assigned by the system when the process is created.
    When you specify a PID, you can omit the leading zeros.

    If you use the /IDENTIFICATION qualifier, the process-name
    parameter is ignored.

                                   NOTE

       The /IDENTIFICATION qualifier allows the SET PROCESS command
       to affect individual kernel thread PIDs; because each thread
       is a separate runnable entity, this command treats them as
       discrete entities in terms of affinities and capabilities.