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 CURLMIMEOPT_* defines. 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);
}
}

AVAILABILITY

Added in curl 7.81.0

RETURN VALUE

Returns CURLE_OK

SEE ALSO

CURLOPT_HTTPPOST(3), CURLOPT_MIMEPOST(3)