CURLOPT_AUTOREFERER explained

Name

CURLOPT_AUTOREFERER - automatically update the referer header

Synopsis

#include <curl/curl.h>
 
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_AUTOREFERER, long autorefer);

Description

Pass a long parameter set to 1 to enable this. When enabled, libcurl automatically sets the Referer: header field in HTTP requests to the full URL when it follows a Location: redirect to a new destination.

The automatic referer is set to the full previous URL even when redirects are done cross-origin or following redirects to insecure protocols. This is considered a minor privacy leak by some.

With CURLINFO_REFERER, applications can extract the actually used referer header after the transfer.

Default

0, disabled

Protocols

This functionality affects http only

Example

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
 
    /* follow redirects */
    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
 
    /* set Referer: automatically when following redirects */
    curl_easy_setopt(curl, CURLOPT_AUTOREFERER, 1L);
 
    res = curl_easy_perform(curl);
 
    curl_easy_cleanup(curl);
  }
}

Availability

Added in curl 7.1

Return value

curl_easy_setopt returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors.