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

 Message        The Compaq C compiler conforms to the C standard and
                will give this constant an unsigned type.  Some older
                compilers may give this constant a signed type.

 Description    The C standard specifies that an octal or hexadecimal
                integer constant has an unsigned type when its value
                cannot be represented in a signed integer type, but
                can be represented in the corresponding unsigned
                integer type.  Some older compilers will treat this
                constant as having a signed type.

 User Action    Be aware of this difference if you plan to port this
                source to an older compiler.