/USE_LINK_INPUT[=filename]
      /NOUSE_LINK_INPUT (D)

  By default, CXXLINK creates a temporary .OPT file in the
  [.cxx_repository] directory.  If the [.cxx_repository]
  directory does not exist, the .OPT file is created in the
  users current directory.  CXXLINK deletes this file.

  If you specify /USE_LINK_INPUT, CXXLINK saves the option file passed
  to LINK in a file named CXX_REPOSITORY.OPT in the user's current
  directory (SYS$DISK:[]CXX_REPOSITORY.OPT).  CXXLINK does not delete
  this file.

  If you specify /USE_LINK_INPUT=filename CXXLINK saves the option
  file passed to LINK in the filename specified.  Because the temporary
  file that CXXLINK uses is renamed to the file name specified,
  "filename" must reside on the same disk as the [.CXX_REPOSITORY]
  directory. CXXLINK does not delete this file.