CURLOPT_LOCALPORT were used together (the local port bind failed), and
  Markus Koetter provided the fix!

changed HAVE_SIN6_SCOPE_ID define to HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID since just found that ares already uses this define.

fix compilation on Cell (reported by Jeff Curley).

non-blocking mode, and decouple function detection from function capability.

which now also takes a protocol address family argument.

  problem with my CURLINFO_PRIMARY_IP fix from October 7th that caused a NULL
  pointer read. I also took the opportunity to clean up this logic (storing of
  the connection's IP address) somewhat as we had it stored in two different
  places and ways previously and they are now unified.

and isn't strictly needed here.

And on the other hand a message after setsockopt() certainly must use SOCKERRNO.

systems supporting getifaddrs(). Also fixed a problem where an IPv6
address could be chosen instead of an IPv4 one for --interface when it
involved a name lookup.

1021 and 1067.

  parser to allow numerical IPv6-addresses to be specified with the scope
  given, as per RFC4007 - with a percent letter that itself needs to be URL
  escaped. For example, for an address of fe80::1234%1 the HTTP URL is:
  "http://[fe80::1234%251]/"

an IPv6 address.

  curl_easy_getinfo. It returns a pointer to a string with the most recently
  used IP address. Modified test case 500 to also verify this feature. The
  implementing of this feature was sponsored by Lenny Rachitsky at NeuStar.

  and receive data over a connection previously setup with curl_easy_perform()
  and its CURLOPT_CONNECT_ONLY option. The sendrecv.c example was added to
  show how they can be used.

  since libcurl used getprotobyname() and that isn't thread-safe. We now
  switched to use IPPROTO_TCP unconditionally, but perhaps the proper fix is
  to detect the thread-safe version of the function and use that.
  http://curl.haxx.se/mail/lib-2008-05/0011.html

  uses the CURLOPT_OPENSOCKETFUNCTION callback to create a unix domain socket
  to a http server.

  them all use the same (hopefully correct) logic to make it less error-prone
  and easier to introduce library-wide where it should be used.

consistency

This happened because the tftp code always uncondionally did a bind()
without caring if one already had been done and then it failed. I wrote a
test case (1009) to verify this, but it is a bit error-prone since it will
have to pick a fixed local port number and since the tests are run on so
many different hosts in different situations I add it in disabled state.

warnings, one C99 thing and the bad pointer sent to the callback

CURLOPT_OPENSOCKETDATA to set a callback that allows an application to replace
the socket() call used by libcurl. It basically allows the app to change
address, protocol or whatever of the socket. (I also did some whitespace
indent/cleanups in lib/url.c which kind of hides some of these changes, sorry
for mixing those in.)

sockets.

and allow reuse by multiple protocols. Several unused error codes were
removed.  In all cases, macros were added to preserve source (and binary)
compatibility with the old names.  These macros are subject to removal at
a future date, but probably not before 2009.  An application can be
tested to see if it is using any obsolete code by compiling it with the
CURL_NO_OLDIES macro defined.

Documented some newer error codes in libcurl-error(3)

passed to it with curl_easy_setopt()! Previously it has always just refered
to the data, forcing the user to keep the data around until libcurl is done
with it. That is now history and libcurl will instead clone the given
strings and keep private copies.

(http://curl.haxx.se/bug/view.cgi?id=1750274) and submitted a patch for the
case where libcurl did a connect attempt to a non-listening port and didn't
provide a human readable error string back.