bizarre configuration error on the SGI

[Byron Rakitzis <byron>]

If you compile rc-1.4beta as-is on the SGI, then globbing will fail under
certain peculiar circumstances (for me: globbing in an NFS-mounted directory
from a NeXT. NOT from a Sun or another SGI, just a NeXT).

After some hair-pulling, I figured out that SGI has two different versions
of opendir & friends (!) one for BSD and one for System V. I guess one uses
"struct direct" and the other one "struct DIR", though it beats me why they
need to have both.

So anyway, it turns out that the BSD version is flawed, and that somehow
rc was getting compiled with that version instead of the SysV opendir. A
little more hunting showed that it's my fault: my config.h sets "NODIRENT"
if the macro "host_mips" is defined. Now, I was informed that this macro
was probably unique to RISCos machines, but lo and behold, SGI defines
it also.

So:

1) if you are compiling 1.4beta on an SGI, you need to edit config.h to
take out the #ifdef host_mips stuff.

2) if you have a RISCos machine, PLEASE let me know what a unique-to-RISCos
preprocessor macro might be.