curl_mime_filedata man page

curl_mime_filedata — set a mime part's body data from a file contents


#include <curl/curl.h>

CURLcode curl_mime_filedata(curl_mimepart * part, const char * filename);


curl_mime_filedata(3) sets a mime part's body content from the named file's contents. This is an alernative to curl_mime_data(3) for setting data to a mime part.

part is the part's to assign contents to.

filename points to the nul-terminated file's path name. The pointer can be NULL to detach the previous part contents settings.  Filename storage can be safely be reused after this call.

As a side effect, the part's remote file name is set to the base name of the given filename if it is a valid named file. This can be undone or overridden by a subsequent call to curl_mime_filename(3).

The contents of the file is read during the file transfer in a streaming manner to allow huge files to get transferred without using much memory. It therefore requires that the file is kept intact during the entire request.

If the file size cannot be determined before actually reading it (such as for a device or named pipe), the whole mime structure containing the part will be transferred as chunks by HTTP and rejected by IMAP.

Setting a part's contents twice is valid: only the value set by the last call is retained.


As long as at least one of HTTP, SMTP or IMAP is enabled. Added in 7.56.0.

Return Value

CURLE_OK or a CURL error code upon failure. CURLE_READ_ERROR is only an indication that the file is not yet readable: it can be safely ignored at this time, but the file must be made readable before the pertaining easy handle is performed.


 curl_mime *mime;
 curl_mimepart *part;

 /* create a mime handle */
 mime = curl_mime_init(easy);

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

 /* send data from this file */
 curl_mime_filedata(part, "image.png");

 /* set name */
 curl_mime_name(part, "data");

See Also

curl_mime_addpart(3), curl_mime_data(3), curl_mime_filename(3), curl_mime_name(3)

Referenced By

curl_mime_addpart(3), curl_mime_filename(3), libcurl-tutorial(3).

January 14, 2018 libcurl 7.59.0 libcurl Manual