NAME

       curl_mime_encoder - set a mime part's encoder and content transfer encoding

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_mime_encoder(curl_mimepart *part, const char *encoding);

DESCRIPTION

       curl_mime_encoder() requests a mime part's content to be encoded before being transmitted.

       part  is  the  part's  handle  to assign an encoder.  encoding is a pointer to a null-terminated encoding
       scheme. It may be set to NULL to disable an encoder previously attached to the part. The encoding  scheme
       storage may safely be reused after this function returns.

       Setting a part's encoder multiple times is valid: only the value set by the last call is retained.

       Upon  multipart  rendering,  the  part's  content  is  encoded  according  to the pertaining scheme and a
       corresponding "Content-Transfer-Encoding" header is added to the part.

       Supported encoding schemes are:

       "binary": the data is left unchanged, the header is added.

       "8bit": header added, no data change.

       "7bit": the data is unchanged, but is each byte is checked to be a 7-bit value;  if  not,  a  read  error
       occurs.

       "base64":  Data  is  converted  to  base64  encoding,  then  split in CRLF-terminated lines of at most 76
       characters.

       "quoted-printable": data is encoded in quoted printable  lines  of  at  most  76  characters.  Since  the
       resulting  size  of the final data cannot be determined prior to reading the original data, it is left as
       unknown, causing chunked transfer in HTTP. For the same reason, this encoder may not be used  with  IMAP.
       This encoder targets text data that is mostly ASCII and should not be used with other types of data.

       If  the  original  data  is  already  encoded in such a scheme, a custom Content-Transfer-Encoding header
       should be added with curl_mime_headers(3) instead of setting a part encoder.

       Encoding should not be applied to multiparts, thus the use of this function on a part  with  content  set
       with curl_mime_subparts(3) is strongly discouraged.

PROTOCOLS

       This functionality affects http, imap and smtp

EXAMPLE

       int main(void)
       {
         curl_mime *mime;
         curl_mimepart *part;

         CURL *curl = curl_easy_init();
         if(curl) {
           /* create a mime handle */
           mime = curl_mime_init(curl);

           /* add a part */
           part = curl_mime_addpart(mime);

           /* send a file */
           curl_mime_filedata(part, "image.png");

           /* encode file data in base64 for transfer */
           curl_mime_encoder(part, "base64");
         }
       }

AVAILABILITY

       Added in curl 7.56.0

RETURN VALUE

       This function returns a CURLcode indicating success or error.

       CURLE_OK  (0)  means  everything  was  OK,  non-zero  means  an error occurred, see libcurl-errors(3). If
       CURLOPT_ERRORBUFFER(3) was set with curl_easy_setopt(3) there can be an error message stored in the error
       buffer when non-zero is returned.

SEE ALSO

       curl_mime_addpart(3), curl_mime_headers(3), curl_mime_subparts(3)

libcurl                                            2025-03-05                               curl_mime_encoder(3)