/sys$common/syshlp/helplib.hlb PRODUCT, INSTALL, Qualifiers, /TRACE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /TRACE
       /NOTRACE (default)

    Displays all DCL commands that the POLYCENTER Software
    Installation utility may execute while performing the operation.
    Any output generated by these commands is also displayed. This
    qualifier is a debugging aid to trace the execution of DCL
    commands and command procedures executed in a subprocess.