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

 Message        Strict standard C extension:  The declaration of the
                "main" function has a return type other than int.

 Description    Standard C requires that the "main" function be
                defined with a return type of int.  Compaq C will
                accept other return types, but the program does not
                conform to the C standard.  The status value returned
                to the environment may not be what you expect, and
                other C compilers may not accept the definition as
                written.

 User Action    Define the "main" function with a return type of int
                for maximal portability.