On Tue, 19 Nov 2002, Yann Golanski wrote:
> How about playing it safe? If gethostbyname() return NULL then do a
> gethostbydns() and see what it returns. Yes, it's slightly unefficent
> but will mean that you are still able to fall back on something that
> will work and not bounce emails.
That's an interesting idea. There is, however, a snag. People use byname
when they are disconnected from the Internet and their nameservers (e.g.
for routing round a small private network). They may well have set up
gethostbyname() _not_ to do DNS lookups. So while I think this could be
useful, there must be a way of switching it off.
Hmm. How about the following:
Default: call gethostbyname(), if returns NULL, try DNS lookup
byname just do gethostbyname()
bydns just do DNS lookup
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.