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
       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_HTTP_VERSION(3), CURLOPT_SSLVERSION(3)

libcurl                           2025-02-13         CURLOPT_HTTP09_ALLOWED(3)