TODO: Added SMTP and POP3 specific features

 8.3 check connection

 8.4 non-gcrypt

 9. Other protocols

 10. New protocols

 10.1 RSYNC

 11. Client

 11.1 sync

 11.2 glob posts

 11.3 prevent file overwriting

 11.4 simultaneous parallel transfers

 11.5 provide formpost headers

 11.6 url-specific options

 11.7 metalink support

 11.8 warning when setting an option

 11.9 IPv6 addresses with globbing

 12. Build

 12.1 roffit

 13. Test suite

 13.1 SSL tunnel

 13.2 nicer lacking perl message

 13.3 more protocols supported

 13.4 more platforms supported

 14. Next SONAME bump

 14.1 http-style HEAD output for ftp

 14.2 combine error codes

 14.3 extend CURLOPT_SOCKOPTFUNCTION prototype

 15. Next major release

 15.1 cleanup return codes

 15.2 remove obsolete defines

 15.3 size_t

 15.4 remove several functions

 15.5 remove CURLOPT_FAILONERROR

 15.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE

 15.7 remove progress meter from libcurl

 15.8 remove 'curl_httppost' from public

 15.9 have form functions use CURL handle argument

 9. SMTP

 9.1 Other authentication mechanims

 9.2 Specify the preferred authentication mechanism

 9.3 Initial response

 9.4 Pipelining

 10 POP3

 10.1 APOP Authentication

 10.2 Other authentication mechanims

 10.3 auth= in URLs

 11. Other protocols

 12. New protocols

 12.1 RSYNC

 13. Client

 13.1 sync

 13.2 glob posts

 13.3 prevent file overwriting

 13.4 simultaneous parallel transfers

 13.5 provide formpost headers

 13.6 url-specific options

 13.7 metalink support

 13.8 warning when setting an option

 13.9 IPv6 addresses with globbing

 14. Build

 14.1 roffit

 15. Test suite

 15.1 SSL tunnel

 15.2 nicer lacking perl message

 15.3 more protocols supported

 15.4 more platforms supported

 16. Next SONAME bump

 16.1 http-style HEAD output for ftp

 16.2 combine error codes

 16.3 extend CURLOPT_SOCKOPTFUNCTION prototype

 17. Next major release

 17.1 cleanup return codes

 17.2 remove obsolete defines

 17.3 size_t

 17.4 remove several functions

 17.5 remove CURLOPT_FAILONERROR

 17.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE

 17.7 remove progress meter from libcurl

 17.8 remove 'curl_httppost' from public

 17.9 have form functions use CURL handle argument

==============================================================================

 The correct fix would be to detect which crypto layer that is in use and

 adapt our code to use that instead of blindly assuming gcrypt.

9. Other protocols

9. SMTP

10. New protocols

9.1 Other authentication mechanims

10.1 RSYNC

 Add support for other authentication mechanisms such as digest-md5 and

 gssapi.

 There's no RFC for protocol nor URI/URL format.  An implementation should

 most probably use an existing rsync library, such as librsync.

9.2 Specify the preferred authentication mechanism

11. Client

 Add the ability to specify the preferred authentication mechanism or a list

 of mechanims that should be used. Not only that, but the order that is

 returned by the server during the EHLO response should be honored by curl.

11.1 sync

9.3 Initial response

 Add the ability for the user to specify whether the initial response is

 included in the AUTH command. Some email servers, such as Microsoft

 Exchange, can work with either whilst others need to have the initial

 response sent separately:

 http://curl.haxx.se/mail/lib-2012-03/0114.html

9.4 Pipelining

 Add support for pipelining emails.

10 POP3

10.1 APOP Authentication

 Add support for the APOP command rather than using plain text authentication

 (USER and PASS) as this is very week security wise. Note: The APOP command

 is specified as "APOP <username> <md5 password>", however, it isn't

 supported by all mail servers.

10.2 Other authentication mechanims

 SASL offers support for additional authentication mechanisms via the AUTH

 command. Detection of an email server's support for SASL authentication

 can be detected via the CAPA command whilst a list of supported mechanisms

 can be retrieved with an empty AUTH command.

10.3 auth= in URLs

 Being able to specify the preferred authentication mechanim in the URL as

 per RFC-2384 (http://tools.ietf.org/html/rfc2384).

11. Other protocols

12. New protocols

12.1 RSYNC

 There's no RFC for the protocol or an URI/URL format.  An implementation

 should most probably use an existing rsync library, such as librsync.

13. Client

13.1 sync

 "curl --sync http://example.com/feed[1-100].rss" or

 "curl --sync http://example.net/{index,calendar,history}.html"

 remote file is newer than the local file. A Last-Modified HTTP date header

 should also be used to set the mod date on the downloaded file.

11.2 glob posts

13.2 glob posts

 Globbing support for -d and -F, as in 'curl -d "name=foo[0-9]" URL'.

 This is easily scripted though.

11.3 prevent file overwriting

13.3 prevent file overwriting

 Add an option that prevents cURL from overwriting existing local files. When

 used, and there already is an existing file with the target file name

 existing). So that index.html becomes first index.html.1 and then

 index.html.2 etc.

11.4 simultaneous parallel transfers

13.4 simultaneous parallel transfers

 The client could be told to use maximum N simultaneous parallel transfers and

 then just make sure that happens. It should of course not make more than one

 connection to the same remote host. This would require the client to use the

 multi interface. http://curl.haxx.se/bug/feature.cgi?id=1558595

11.5 provide formpost headers

13.5 provide formpost headers

 Extending the capabilities of the multipart formposting. How about leaving

 the ';type=foo' syntax as it is and adding an extra tag (headers) which

 which should overwrite the program reasonable defaults (plain/text,

 8bit...)

11.6 url-specific options

13.6 url-specific options

 Provide a way to make options bound to a specific URL among several on the

 command line. Possibly by letting ':' separate options between URLs,

 The example would do a POST-GET-POST combination on a single command line.

11.7 metalink support

13.7 metalink support

 Add metalink support to curl (http://www.metalinker.org/). This is most useful

 with simultaneous parallel transfers (11.6) but not necessary.

11.8 warning when setting an option

13.8 warning when setting an option

  Display a warning when libcurl returns an error when setting an option.

  This can be useful to tell when support for a particular feature hasn't been

  compiled into the library.

11.9 IPv6 addresses with globbing

13.9 IPv6 addresses with globbing

  Currently the command line client needs to get url globbing disabled (with

  -g) for it to support IPv6 numerical addresses. This is a rather silly flaw

  that should be corrected. It probably involves a smarter detection of the

  '[' and ']' letters.

12. Build

14. Build

12.1 roffit

14.1 roffit

 Consider extending 'roffit' to produce decent ASCII output, and use that

 instead of (g)nroff when building src/hugehelp.c

13. Test suite

15. Test suite

13.1 SSL tunnel

15.1 SSL tunnel

 Make our own version of stunnel for simple port forwarding to enable HTTPS

 and FTP-SSL tests without the stunnel dependency, and it could allow us to

 provide test tools built with either OpenSSL or GnuTLS

13.2 nicer lacking perl message

15.2 nicer lacking perl message

 If perl wasn't found by the configure script, don't attempt to run the tests

 but explain something nice why it doesn't.

13.3 more protocols supported

15.3 more protocols supported

 Extend the test suite to include more protocols. The telnet could just do ftp

 or http operations (for which we have test servers).

13.4 more platforms supported

15.4 more platforms supported

 Make the test suite work on more platforms. OpenBSD and Mac OS. Remove

 fork()s and it should become even more portable.

14. Next SONAME bump

16. Next SONAME bump

14.1 http-style HEAD output for ftp

16.1 http-style HEAD output for ftp

 #undef CURL_FTP_HTTPSTYLE_HEAD in lib/ftp.c to remove the HTTP-style headers

 from being output in NOBODY requests over ftp

14.2 combine error codes

16.2 combine error codes

 Combine some of the error codes to remove duplicates.  The original

 numbering should not be changed, and the old identifiers would be

    CURLE_TFTP_NOTFOUND => CURLE_REMOTE_FILE_NOT_FOUND

    CURLE_TFTP_PERM => CURLE_REMOTE_ACCESS_DENIED

14.3 extend CURLOPT_SOCKOPTFUNCTION prototype

16.3 extend CURLOPT_SOCKOPTFUNCTION prototype

 The current prototype only provides 'purpose' that tells what the

 connection/socket is for, but not any protocol or similar. It makes it hard

 for applications to differentiate on TCP vs UDP and even HTTP vs FTP and

 similar.

15. Next major release

17. Next major release

15.1 cleanup return codes

17.1 cleanup return codes

 curl_easy_cleanup() returns void, but curl_multi_cleanup() returns a

 CURLMcode. These should be changed to be the same.

15.2 remove obsolete defines

17.2 remove obsolete defines

 remove obsolete defines from curl/curl.h

15.3 size_t

17.3 size_t

 make several functions use size_t instead of int in their APIs

15.4 remove several functions

17.4 remove several functions

 remove the following functions from the public API:

 curl_multi_socket_all

15.5 remove CURLOPT_FAILONERROR

17.5 remove CURLOPT_FAILONERROR

 Remove support for CURLOPT_FAILONERROR, it has gotten too kludgy and weird

 internally. Let the app judge success or not for itself.

15.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE

17.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE

 Remove support for a global DNS cache. Anything global is silly, and we

 already offer the share interface for the same functionality but done

 "right".

15.7 remove progress meter from libcurl

17.7 remove progress meter from libcurl

 The internally provided progress meter output doesn't belong in the library.

 Basically no application wants it (apart from curl) but instead applications

 variable types passed to it instead of doubles so that big files work

 correctly.

15.8 remove 'curl_httppost' from public

17.8 remove 'curl_httppost' from public

 curl_formadd() was made to fill in a public struct, but the fact that the

 struct is public is never really used by application for their own advantage

 Changing them to return a private handle will benefit the implementation and

 allow us much greater freedoms while still maintining a solid API and ABI.

15.9 have form functions use CURL handle argument

17.9 have form functions use CURL handle argument

 curl_formadd() and curl_formget() both currently have no CURL handle

 argument, but both can use a callback that is set in the easy handle, and