On Sun, Feb 22, 2015 at 08:58:10PM -0600, Josiah Worcester wrote:
> when we fail to find the entry in the commonly accepted files,  we
> query a server over a Unix domain socket on /var/run/nscd/socket.
> the protocol used here is compatible with glibc's nscd protocol on
> most systems (all that use 32-bit numbers for all the protocol fields,
> which appears to be everything but Alpha).

I'm committing with the attached additional changes amended in as
discussed on #musl. With these changes it at least passes the
following checks:

- With no nscd running, lookups return negative with no error.

- With bad nscd running and dropping connections with no reply,
  reverse-endian fallback code retries the query and then fails with
  EIO indicating inability to provide a definitive negative answer.

- Replies that don't match the query produce EIO.

- Replies that do match the query produce successful results.

Tested using the attached fake-nscd.c. This code still needs further
testing before release to ensure that we're not introducing
significant bugs.

Rich