curl_mime_encoder() is operational and documented. curl tool -F option is extended with ";encoder=". curl tool --libcurl option generates calls to curl_mime_encoder(). New encoder tests 648 & 649. Test 1404 extended with an encoder specification.
Available in HTTP, SMTP and IMAP. Deprecates the FORM API. See CURLOPT_MIMEPOST. Lib code and associated documentation.