CURLOPT_MIMEPOST − set post/send data from mime structure
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_MIMEPOST, mime);
Pass a mime handle previously obtained from curl_mime_init(3).
This setting is supported by the HTTP protocol to post forms and by the SMTP and IMAP protocols to provide the e-mail data to send/upload.
This option is the preferred way of posting an HTTP form, replacing and extending the deprecated CURLOPT_HTTPPOST(3) option.
HTTP, SMTP, IMAP.
This will return CURLE_OK.
Using this option implies the use of several mime structure building functions: see https://curl.haxx.se/libcurl/c/smtp-mime.html for a complete example.