CURLOPT_MIME_OPTIONS - set MIME option flags

NAME SYNOPSIS DESCRIPTION DEFAULT PROTOCOLS EXAMPLE HISTORY AVAILABILITY RETURN VALUE SEE ALSO

NAME

CURLOPT_MIME_OPTIONS − set MIME option flags

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_MIME_OPTIONS, long options);

DESCRIPTION

Pass a long that holds a bitmask of options. Each bit is a boolean flag used while encoding a MIME tree or multipart form data.

Available bits are:
CURLMIMEOPT_FORMESCAPE

Tells libcurl to escape multipart form field and filenames using the backslash−escaping algorithm rather than percent−encoding (HTTP only).

Backslash−escaping consists in preceding backslashes and double quotes with a backslash. Percent encoding maps all occurrences of double quote, carriage return and line feed to %22, %0D and %0A respectively.

Before version 7.81.0, percent−encoding was never applied.

HTTP browsers used to do backslash−escaping in the past but have over time transitioned to use percent−encoding. This option allows one to address server−side applications that have not yet have been converted.

As an example, consider field or filename strangename"kind. When the containing multipart form is sent, this is normally transmitted as strangename%22kind. When this option is set, it is sent as strangename"kind.

DEFAULT

0, meaning disabled.

PROTOCOLS

This functionality affects http, imap and smtp

EXAMPLE

int main(void)
{
CURL *curl = curl_easy_init();
curl_mime *form = NULL;

if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
curl_easy_setopt(curl, CURLOPT_MIME_OPTIONS, CURLMIMEOPT_FORMESCAPE);

form = curl_mime_init(curl);
if(form) {
curl_mimepart *part = curl_mime_addpart(form);

if(part) {
curl_mime_filedata(part, "strange\\file\\name");
curl_mime_name(part, "strange\"field\"name");
curl_easy_setopt(curl, CURLOPT_MIMEPOST, form);

/* Perform the request */
curl_easy_perform(curl);
}
}

curl_easy_cleanup(curl);
curl_mime_free(form);
}
}