curl_mime_subparts - set sub-parts of a multipart mime part

Added in curl 7.56.0

curl_mime_subparts(3) sets a multipart mime part's content from a mime structure. part is a handle to the multipart part. subparts is a mime structure handle holding the sub-parts. After curl_mime_subparts(3) succeeds, the mime structure handle belongs to the multipart part and must not be freed explicitly. It may however be updated by subsequent calls to mime API functions. Setting a part's contents multiple times is valid: only the value set by the last call is retained. It is possible to unassign previous part's contents by setting subparts to NULL.

static char *inline_html = "<title>example</title>"; static char *inline_text = "once upon the time"; int main(void) { CURL *curl = curl_easy_init(); if(curl) { struct curl_slist *slist; /* The inline part is an alternative proposing the html and the text versions of the email. */ curl_mime *alt = curl_mime_init(curl); curl_mimepart *part; /* HTML message. */ part = curl_mime_addpart(alt); curl_mime_data(part, inline_html, CURL_ZERO_TERMINATED); curl_mime_type(part, "text/html"); /* Text message. */ part = curl_mime_addpart(alt); curl_mime_data(part, inline_text, CURL_ZERO_TERMINATED); /* Create the inline part. */ part = curl_mime_addpart(alt); curl_mime_subparts(part, alt); curl_mime_type(part, "multipart/alternative"); slist = curl_slist_append(NULL, "Content-Disposition: inline"); curl_mime_headers(part, slist, 1); } }

curl_mime_subparts - set sub-parts of a multipart mime part

This functionality affects http, imap and smtp

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.

curl_mime_addpart(3), curl_mime_init(3) libcurl 2025-06-16 curl_mime_subparts(3)

#include <curl/curl.h> CURLcode curl_mime_subparts(curl_mimepart *part, curl_mime *subparts);