Thank you, importantly you've answered my question that it is not possible.
May I complete the record then and respectfully disagree with your assessment of the merit. I quote from RFC7231:
and from 7230:
The reason-phrase element exists for the sole purpose of providing a
textual description associated with the numeric status code, mostly
out of deference to earlier Internet application protocols that were
more frequently used with interactive text clients. A client SHOULD
ignore the reason-phrase content.
reason-phrase = *( HTAB / SP / VCHAR / obs-text )
Regards
>Only by changing the source code and recompiling MHD. But you should not
>do this, this is a very bad idea. You should stick to the standard
>messages of the HTTP protocol. If you need to convey additional
>information, do it in the body or in a header; try to use HTTP status
>codes narrowly to what the HTTP standard says they are for.
>On 12/5/22 10:26, Tiaan via libmicrohttpd wrote:
>> Hi, is it possible to change the reason phrase of responses e.g. instead of
>> HTTP/1.1 401 Unauthorized rather HTTP/1.1 401 Account frozen?
>>