Avoid problems with glibc's _res symbol

[Stefan Jones]

Mike McCormack said:
>
> Hi Mike,
>
> No, unfortunately it's supposed to be a "well known" global symbol. It's
> even mentioned in the manual page for resolver(3).
>

So is errno, but that doesn't exist either, but get's #defined to
__get_errno_loc() (or something). _res turns to _res_state() I think.

PS. This breaks netscape-4.7?? on nptl + glibc as it uses _res

Stefan