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.TH CURLOPT_HTTP09_ALLOWED 3 "September 26, 2023" "ibcurl 8.4.0" libcurl

.SH NAME
CURLOPT_HTTP09_ALLOWED \- allow HTTP/0.9 response
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP09_ALLOWED, long allowed);
.fi
.SH DESCRIPTION
Pass the long argument \fIallowed\fP 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!
.SH DEFAULT
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.
.SH PROTOCOLS
HTTP
.SH EXAMPLE
.nf
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);
}
.fi
.SH AVAILABILITY
Option added in 7.64.0, present along with HTTP.
.SH RETURN VALUE
Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_HTTP_VERSION (3),
.BR CURLOPT_SSLVERSION (3)