I appear to have missed the beginning of this.  Probably all for the best.

> > #define SEG_VALUE 20 //A C++ type commment is better.
> > 		/* SEG_VALUE This is a SEG_VALUE */
> > #define SEG_VALUE 20
> > Is more portable, but more verbose but more error proof.

> What is the advantage of this vs. the above (initial) one?

I happen to personally like that style, if for no other reason than you can
put longer comments in without wrapping 80-column lines.  (See the sound
blaster driver for an example of what happens when someone concludes that
the best way to enhance his communication to other programmers is to widen
his own xterm window...)  That's a pretty weak advantage, though.

I certainly think there's just about zero value in going through and changing
these comments in existing code, even if there were a distinct advantage.

But while we're whining about comments, I noticed recently that the name
daemon source is filled with

	#endif PREPROCESSOR_SYMBOL

misdirectives.  Assuming there are any architectures on which GCC does not
run :-), there might be some portability gain in changing those to honest
comments...