While I don't speak for Apple, we ran into this with Daylite Server, and found out that you shouldn't be using those calls. Basically, your computer is NOT the authority on your computer's host name. The DNS system is the authority. So these calls tend to trigger DNS lookups, at which point you're at the mercy of DNS, especially badly configured DNS, or DNS servers that are down, or what-have-you.
Beyond that, I haven't worked out all the intricacies. But I believe that gethostname() gets a cached host name that gets set at system startup, and is in no way authoritative (it is I think the C API which underlies the "hostname" command, and has a complementary sethostname command). That old way of doing stuff is pretty much obsolete. Mac OS X always tries to discover its name from DNS first, and falls back to the mDNS if there is no good response from DNS. Or that seems to be what's going on. The Apple engineers at WWDC were appalled by the very idea of NSHost -currentHost and anything related to it, and basically said that if you're using them, you've got problems in your design. Not making any judgements, just relating my (now somewhat fuzzy) experience. On Tue, Sep 8, 2009 at 4:15 PM, jonat...@mugginsoft.com < jonat...@mugginsoft.com> wrote: > I am not sure if this is a problem unique to me or not but under 10.5 > [[NSHost currentHost] name] or [[[NSProcessInfo] processInfo] hostname] were > quick and easy ways to get an mDNS friendly hostname such as imac-2.local > > On 10.6 I find that both these combinations block badly (NSProcessInfo > merely defers to NSHost I think). > > The list has a few references to the possibility of these blocking but I > never encountered it until now. > According to a stack sample getnameinfo() seems to be the library call that > is blocking. > _mdns_query_mDNSResponder seems to be the actual blocking call. > > Anyone else seeing this behaviour? > > There seem to be two alternatives: > > NSString *name = NSMakeCollectable(SCDynamicStoreCopyLocalHostName(NULL)); > > This gives the correct mDNS friendly hostname but omits the local pseudo > domain. > > Otherwise this seems suitable: > > char hostname[_POSIX_HOST_NAME_MAX + 1]; > gethostname(hostname, _POSIX_HOST_NAME_MAX); > name = [NSString stringWithCString:hostname encoding:NSUTF8StringEncoding]; > > Jonathan Mitchell > > Developer > http://www.mugginsoft.com > > > > > > _______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/cocoa-dev/bgulanowski%40gmail.com > > This email sent to bgulanow...@gmail.com > -- Brent Gulanowski _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
