> I got this code of the net ...

    Looks like you got about what you paid for it.  I don't know who this Eric
    Smith guy is that claims to have written it, but I would stay away from
    anything else that has his name on it.


    > ringadv macro ptr,base,size
    >  local pow2,aligned,bit,val
    > pow2 SET !(size&(size-1))
    > aligned SET pow2&&((base&(size-1))==0)
    >
    >  if aligned
    > val set size
    > bit set 0
    >  while val>1
    > bit set bit+1
    > val set val>>1
    >  endw
    >  endif
    >

    Good thing it's so well commented!

Indeed.  An interesting example of portability (or the lack thereof.)  In an
effort to make the code portable/usable on a wide variety of PICs (circa
1997) with assorted memory layouts, it has become all but incomprehensible
to anyone who couldn't have written their own code in the first place.
Obscure and powerful conditional assembly; Oh My!  Add five years an another
generation or two of PICs and it loses much of it's utility.  :-(

I'd blame this on assembler, except I see the same sort of thing ALL THE
TIME with C programs from a certain era.  Lovely incomprehensible make files
and preprocessor directives so that the code will compile under 4.2BSD, AT&T
SysV, SunOS 3.2, HP SysV, MSDOS using turbo-C, MSDOS using MS C, etc.  Try
to figure out what needs to be done in a modern Posix/windows environment,
and you're lost unless you're not only a unix wizard, but also a wizard in
at least one variety of obsolete unix :-(

BillW

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