RFC 2068:Hypertext Transfer Protocol -- HTTP/1.1
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Error Response


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... servicing a request, as described in section 12. The representation of entities in any response can be negotiated (including error responses). variant ...


... of this request. 5. Wait either for an error response from the server, or for T seconds (whichever comes first) ...
... (whichever comes first) 6. If no error response is received, after T seconds transmit the body of the request. ...
... client sees that the connection is closed prematurely, repeat from step 1 until the request is accepted, an error response is received, or the user becomes impatient and terminates the retry process. ...


... created or modified with the Request-URI, an appropriate error response SHOULD be given that reflects the nature of the problem. The recipient of the entity MUST NOT ignore any Content-* ...


... subject to negotiation, including error responses. There are two kinds of content negotiation ...


... Accept-Charset header, then the server SHOULD send an error response with the 406 (not acceptable) status code, though the sending of an unacceptable response is also allowed. ...
... which is acceptable according to the Accept-Encoding header, then the server SHOULD send an error response with the 406 (Not Acceptable) status code. ...



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