How to determine content-data length from chunked encoding if HTTP header not sent

http content-length chunked
Mohamad Elmasri picture Mohamad Elmasri · Feb 8, 2011 · Viewed 12.5k times · Source

How to determine the content-data length if the header is not sent and instead you receive Transfer-Encoding: chunked header?

Answer

Ciaran Keating picture Ciaran Keating · Feb 8, 2011

With chunked encoding there will be no Content-Length header. So after you've read the headers and the pair of CRLFs that mark the end of the headers, you're ready to read the first chunk. Each chunk payload is preceded by its own mini-header - the length in hex followed by CRLF. And there's another CRLF after the payload, before the next chunk's mini-header. A chunk can also be followed by some optional trailers. The end of the message is indicated by a zero-length chunk.

You can find the definitive details in the HTTP RFC, RFC2616.

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