VMS Help CC, Messages, CDDEXT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        #dictionary is a language extension.

 Description    The #dictionary directive is an extension of Compaq
                C/C++ on OpenVMS.  The program might not compile with
                other compilers or on other platforms.

 User Action    Be aware of this if you wish to port the program.