CURLOPT_SOCKS5_GSSAPI_SERVICE and CURLOPT_SOCKS5_GSSAPI_NEC to allow libcurl
  to do GSS-style authentication with SOCKS5 proxies. The curl tool got the
  options called --socks5-gssapi-service and --socks5-gssapi-nec to enable
  these.

  to set desired block size to use for TFTP transfers instead of the default
  512 bytes.

  They basically offer the same thing the NO_PROXY environment variable only
  offered previously: list a set of host names that shall not use the proxy
  even if one is specified.

clarity.  This does fix one problem that causes ;type=i FTP URLs
to fail in the Turkish locale when CURLOPT_PROXY_TRANSFER_MODE is
used (test case 561)

Added tests 561 and 1092 through 1094 to test various combinations
of ;type= and ;mode= URLs that could potentially fail in the Turkish
locale.

curl_easy_reset() by creating Curl_init_userdefined(). This had the side effect
of fixing curl_easy_reset() so it now also resets CURLOPT_FTP_FILEMETHOD and
CURLOPT_SSL_SESSIONID_CACHE

  (http://curl.haxx.se/bug/view.cgi?id=2413067) that identified a problem that
  would cause libcurl to mark a DNS cache entry "in use" eternally if the
  subsequence TCP connect failed. It would thus never get pruned and refreshed
  as it should've been.

  now has an improved ability to do right when the multi interface (both
  "regular" and multi_socket) is used for SCP and SFTP transfers. This should
  result in (much) less busy-loop situations and thus less CPU usage with no
  speed loss.

specified data pointer was head.

in the parse_remote_port() function as the scope id has already been stripped
from the string.

  addresses if they were very long (>39 letters) due to a too strict address
  validity parser. It now accepts addresses up to 45 bytes long.

  there are servers "out there" that relies on the client doing this broken
  Digest authentication. Apache even comes with an option to work with such
  broken clients.

  The difference is only for URLs that contain a query-part (a '?'-letter and
  text to the right of it).

  libcurl now supports this quirk, and you enable it by setting the
  CURLAUTH_DIGEST_IE bit in the bitmask you pass to the CURLOPT_HTTPAUTH or
  CURLOPT_PROXYAUTH options. They are thus individually controlled to server
  and proxy.

  (http://curl.haxx.se/bug/view.cgi?id=2351645) that identified a problem with
  the multi interface that occured if you removed an easy handle while in
  progress and the handle was used in a HTTP pipeline.

  when uploading files to a single FTP server using multiple easy handle
  handles with the multi interface. Occasionally a handle would stall in
  mysterious ways.

  The problem turned out to be a side-effect of the ConnectionExists()
  function's eagerness to re-use a handle for HTTP pipelining so it would
  select it even if already being in use, due to an inadequate check for its
  chances of being used for pipelnining.

  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.

inclusion by the curl tool without colliding with the curl_strequal functions.

Changed checkprefix() to use it and those instances of strnequal() that
compare host names or other protocol strings that are defined to be
independent of case in the C locale.  This should fix a few more
Turkish locale problems.

by coverity.com

--disable-proxy mode.
Removed some unnecessary prototypes.

CURLOPT_PROXYUSERPWD

  make CURLOPT_PROXYUSERPWD sort of deprecated. The primary motive for adding
  these new options is that they have no problems with the colon separator
  that the CURLOPT_PROXYUSERPWD option does.

used in strequal.c so now all test cases run fine for me again.

  (http://curl.haxx.se/bug/view.cgi?id=2154627) which pointed out that libcurl
  uses strcasecmp() in multiple places where it causes failures when the
  Turkish locale is used. This is because 'i' and 'I' isn't the same letter so
  strcasecmp() on those letters are different in Turkish than in English (or
  just about all other languages). I thus introduced a totally new internal
  function in libcurl (called Curl_ascii_equal) for doing case insentive
  comparisons for english-(ascii?) style strings that thus will make "file"
  and "FILE" match even if the Turkish locale is selected.

_ Update RPG binding accordingly.
_ Fix new options comments.

  curl_easy_setopt: CURLOPT_USERNAME and CURLOPT_PASSWORD that sort of
  deprecates the good old CURLOPT_USERPWD since they allow applications to set
  the user name and password independently and perhaps more importantly allow
  both to contain colon(s) which CURLOPT_USERPWD doesn't fully support.

  the app re-used the handle to do a connection to host B and then again
  re-used the handle to host A, it would not update the info with host A's IP
  address (due to the connection being re-used) but it would instead report
  the info from host B.

  libcurl to somewhat reduce the size of the binary. Run configure
  --disable-proxy.

Curl_resolv_timeout function to reduce coupling.

switching from one protocol to another in a single request (e.g.
redirecting from HTTP to FTP as in test 1055) by resetting
state.expect100header before every request.