http09: disable HTTP/0.9 by default in both tool and library

As the plan has been laid out in DEPRECATED. Update docs accordingly and
verify in test 1174. Now requires the option to be set to allow HTTP/0.9
responses.

Closes #4191

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/url.c b/lib/url.c
index 13d015753..05fc0e50e 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -546,7 +546,7 @@ CURLcode Curl_init_userdefined(struct Curl_easy *data)
   set->upkeep_interval_ms = CURL_UPKEEP_INTERVAL_DEFAULT;
   set->maxconnects = DEFAULT_CONNCACHE_SIZE; /* for easy handles */
   set->maxage_conn = 118;
-  set->http09_allowed = TRUE;
+  set->http09_allowed = FALSE;
   set->httpversion =
 #ifdef USE_NGHTTP2
     CURL_HTTP_VERSION_2TLS