CURLOPT_HAPROXYPROTOCOL(3) Library Functions Manual CURLOPT_HAPROXYPROTOCOL(3)
NAME
CURLOPT_HAPROXYPROTOCOL - send HAProxy PROXY protocol v1 header
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HAPROXYPROTOCOL,
long haproxy_protocol);
DESCRIPTION
A long parameter set to 1 tells the library to send an HAProxy PROXY
protocol v1 header at beginning of the connection. The default action is
not to send this header.
This option is primarily useful when sending test requests to a service
that expects this header.
Most applications do not need this option.
DEFAULT
0, do not send any HAProxy PROXY protocol header
PROTOCOLS
This functionality affects all supported protocols
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode ret;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_HAPROXYPROTOCOL, 1L);
ret = curl_easy_perform(curl);
}
}
AVAILABILITY
Added in curl 7.60.0
RETURN VALUE
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).
SEE ALSO
CURLOPT_PROXY(3)
libcurl 2026-07-12 CURLOPT_HAPROXYPROTOCOL(3)
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