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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_HTTP09_ALLOWED(3) Library Functions Manual CURLOPT_HTTP09_ALLOWED(3)

NAME

CURLOPT_HTTP09_ALLOWED - allow HTTP/0.9 response

SYNOPSIS

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP09_ALLOWED, long allowed);

DESCRIPTION

Pass the long argument allowed set to 1L to allow HTTP/0.9 responses.

An HTTP/0.9 response is a server response entirely without headers and only a body. You can connect to lots of random TCP services and still get a response that curl might consider to be HTTP/0.9.

DEFAULT

0

PROTOCOLS

This functionality affects http only

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_HTTP09_ALLOWED, 1L);
ret = curl_easy_perform(curl);
} }

HISTORY

curl allowed HTTP/0.9 responses by default before 7.66.0

Since 7.66.0, libcurl requires this option set to 1L to allow HTTP/0.9 responses.

AVAILABILITY

Added in curl 7.64.0

RETURN VALUE

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

SEE ALSO

CURLOPT_HTTP_VERSION(3), CURLOPT_SSLVERSION(3)

2025-08-26 libcurl
Copyright 2011-2025 Jonas 'Sortie' Termansen and contributors.
Sortix's source code is free software under the ISC license.
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