CURLOPT\_AUTOREFERER(3) Library Functions Manual CURLOPT\_AUTOREFERER(3)

# [NAME](#NAME)

CURLOPT\_AUTOREFERER - automatically update the referer header

# [SYNOPSIS](#SYNOPSIS)

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

# [DESCRIPTION](#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)*](/man/os/curl/CURLINFO_REFERER.3), applications can extract the actually used referer header after the transfer.

# [DEFAULT](#DEFAULT)

0, disabled

# [PROTOCOLS](#PROTOCOLS)

This functionality affects http only

# [EXAMPLE](#EXAMPLE)

```
int main(void)
{


  CURL *curl = curl_easy_init();


  if(curl) {


    CURLcode result;


    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);


    result = curl_easy_perform(curl);


    curl_easy_cleanup(curl);


  }
}
```

# [AVAILABILITY](#AVAILABILITY)

Added in curl 7.1

# [RETURN VALUE](#RETURN_VALUE)

[*curl\_easy\_setopt(3)*](/man/os/curl/curl_easy_setopt.3) returns a CURLcode indicating success or error.

CURLE\_OK (0) means everything was OK, non-zero means an error occurred, see [*libcurl-errors(3)*](/man/os/curl/libcurl-errors.3).

# [SEE ALSO](#SEE_ALSO)

[**CURLINFO\_EFFECTIVE\_URL**(3)](/man/os/curl/CURLINFO_EFFECTIVE_URL.3), [**CURLINFO\_REDIRECT\_URL**(3)](/man/os/curl/CURLINFO_REDIRECT_URL.3), [**CURLINFO\_REFERER**(3)](/man/os/curl/CURLINFO_REFERER.3), [**CURLOPT\_FOLLOWLOCATION**(3)](/man/os/curl/CURLOPT_FOLLOWLOCATION.3), [**CURLOPT\_REFERER**(3)](/man/os/curl/CURLOPT_REFERER.3)

2026-10-19 libcurl

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Document: CURLOPT_AUTOREFERER(3) from curl 8.23.0-r1 (Chainguard OS)
Source: https://github.com/curl/curl.git