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

     /LIST[=file-spec] (Batch default)
     /NOLIST (Interactive default)

  Controls whether a listing file is produced.  The default output
  file extension is .LIS.

  (Note:  To suppress compiler messages to the terminal or to a batch
  log file, use the /SHOW=NOTERMINAL qualifier.)