IPv6 transport-ready resolvers/DNS servers. need careful configuration
when enable it. (default config is not affected).
see manpage for details.
XXX visible symbol __res_opt() is added, however, it is not supposed to be
called from outside, libc minor is not bumped.
XXX 4.9.5 -> 4.9.7 moves _res from data to bss. the bss version of the code
is committed, but is wrapped with #ifdef __RES_IN_BSS and is disabled
(_res is still in data segment).
descriptors against -1 (as appropriate).
* add actual checks which to detect stuff that would trigger_DIAGASSERT(),
and attempt to return a sane error condition.
* knf some code
* remove some `register' decls.
the first two items result in the addition of code similar to the
following in various functions:
_DIAGASSERT(path != NULL)
#ifdef _DIAGNOSTIC
if (path == NULL) {
errno = EFAULT;
return (-1);
}
#endif
