pidadr

    OpenVMS usage:process_id
    type:         longword (unsigned)
    access:       modify
    mechanism:    by reference
    Process identification (PID) of the process for which wakeups are
    to be canceled. The pidadr argument is the address of a longword
    specifying the PID. The pidadr argument can refer to a process
    running on the local node or a process running on another node in
    the OpenVMS Cluster system.

 prcnam

    OpenVMS usage:process_name
    type:         character-coded text string
    access:       read only
    mechanism:    by descriptor-fixed-length string descriptor
    Name of the process for which wakeups are to be canceled. The
    prcnam argument is the address of a character string descriptor
    pointing to the process name string.

    A process running on the local node can be identified with a 1-
    to 15-character string. To identify a process on a specific node
    in a cluster, specify the full process name, which includes the
    node name as well as the process name. The full process name can
    contain up to 23 characters.

    The operating system interprets the UIC group number of the
    calling process as part of the process name; the names of
    processes are unique to UIC groups. Because of this, you can
    use the prcnam argument only on behalf of processes in the same
    group as the calling process.