RFC 2616:Hypertext Transfer Protocol -- HTTP/1.1
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error code


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... connection with a server. The server responds with a status line, including the message's protocol version and a success or error code, followed by a MIME-like message containing server information, entity ...


... Clarified which error code should be used for inbound server failures (e.g. DNS failures). (Section 10.5.5). ...



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