I've been a zsh user since the mid 90's, but I haven't been able to keep
up with some of the newer developments. zstyle frightens me with its
apparent complexity. I've now hit a problem that's so frustrating that
I'm about ready to ditch zsh and go to bash... unless someone can help?

Completion for ssh and friends (notably scp) attempt to look up NIS
nowadays (I'm using zsh 4.2.0), but when you have 40,000 entries in your
NIS passwd map, this is not a fun experience. Hitting "scp blah<TAB>"
causes the shell to hang for a couple of minutes - there doesn't appear
to be any way to interrupt it.

Is there a way to turn off this NIS lookup for users and hosts? I've
tried defining my own, with a snippet plagiarized from someone else's
config, courtesy of google:

local _myhosts _myusers

_myhosts=($(<~/.zsh/hosts) 
${${${${(f)"$(<$HOME/.ssh/known_hosts)"}:#[0-9]*}%%\ *}%%,*})
_myusers=($(<~/.zsh/users))

zstyle ':completion:*' users $_myusers
zstyle ':completion:*' hosts $_myhosts

and that works so long as I have typed the first few letters of one of
those users or hosts, but if I've typed something that doesn't match,
the NIS lookup, and resulting hang, still occur,

Please help .. before I jump ship to bash .. I really don't want to ...

TIA,

     ~Iain