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Sortix volatile manual

This manual documents Sortix volatile, a development build that has not been officially released. You can instead view this document in the latest official manual.

CURLOPT_AUTOREFERER(3) Library Functions Manual CURLOPT_AUTOREFERER(3)

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

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

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

SEE ALSO

CURLINFO_EFFECTIVE_URL(3), CURLINFO_REDIRECT_URL(3), CURLINFO_REFERER(3), CURLOPT_FOLLOWLOCATION(3), CURLOPT_REFERER(3)
2025-05-14 libcurl
Copyright 2011-2025 Jonas 'Sortie' Termansen and contributors.
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