On 7 Jul 2017, at 7:23 pm, Willy Tarreau <w(_at_)1wt(_dot_)eu> wrote:
Maybe the stronger wording should be oriented differently, such as
"Servers MUST not send 103 to HTTP/1.0 clients nor to any client
known not to support 1xx informational responses" ? This way it
leaves the possibility opened (ie rely on version and/or user-agent
or anything else once an exception is known).
RFC7231 already says "Since HTTP/1.0 did not define any 1xx status codes, a
server MUST NOT send a 1xx response to an HTTP/1.0 client."
Mark Nottingham https://www.mnot.net/