On Wed, 10 Apr 2013, zhangyongchao wrote:

STOP!

You really MUST read the etiquette guidelines we have:
http://curl.haxx.se/mail/etiquette.html

You violated like 3 or 4 of those rules at once. You will not get your desired
level of help or friendliness here if you continue with those violations.

> I trace the libcurl code, locate the problem position, but not known the
> root case. I strongly need your expertise. The trace result list here:

...

> 5. And at last, invoked "Curl_http_done which print out error message "Empty
> reply from server".

All I can see from your analysis is that libcurl points out the obvious to
you: there was no response sent from the server (or rather libcurl couldn't
receive any at least). Nothing at all. In HTTP land that is an error and so
libcurl returns that error.

If wireshark/tcpdump the connection, can you see any data being received by
your client?

-- 
  / daniel.haxx.se
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