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c: Copyright (C) Daniel Stenberg, <daniel.se>, et al. SPDX-License-Identifier: curl Title: CURLOPT_AUTOREFERER Section: 3 Source: libcurl See-also:

• CURLINFO_EFFECTIVE_URL (3)
• CURLINFO_REDIRECT_URL (3)
• CURLINFO_REFERER (3)
• CURLOPT_FOLLOWLOCATION (3)
• CURLOPT_REFERER (3)

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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(3), applications can extract the actually used referer header after the transfer.

DEFAULT

0, disabled

PROTOCOLS

HTTP

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

Along with HTTP

RETURN VALUE

Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.