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

1 - /PARENT

    Indicates that you want to attach to the parent process of your
    current process. If you did not access the Mail utility by using
    the SPAWN command, Mail displays an error message. You cannot
    specify the process-name parameter with the /PARENT qualifier.