usage.

 threaded name resolves.

for it. It saves one extra copy of the header.

I also added comments for several functions in formdata.c

  stuff added a few weeks ago.  Turns out that if you specify --proxy-ntlm and
  communicate with a proxy that requires basic authentication, the proxy
  properly returns a 407, but the failure detection code doesn't realize it
  should give up, so curl returns with exit code 0. Test case 162 verifies
  this.

we won't try to QUIT the control connection and risk "hanging" waiting for
a response. Test case 161 verifies this. The quit-sending function was
also made static.

less

160 shows.

We got no data and we attempted to re-use a connection. This might happen if
the connection was left alive when we were done using it before, but that was
closed when we wanted to read from it again. Bad luck. Retry the same request
on a fresh connect!

Deleted the sockerror variable again, it serves no purpose anymore.

length limit of the hostname part of the URL.

should be used

now cause the resolve function to return NULL immediately

some bad thinking on my part.

when not using ares.

instead to make it easier to find/read

sessionhandle to make the duphandle() function work as supposed. Also tried
to start document functions the doxygen way (in the headers of the functions).
Can't make it work though...

even such platforms?)

is now treated as an error by libcurl

concept, and added lib/README.curlx to explain details about it