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Re: libcurl don't write data directly (internal buffering?)

From: Daniel Stenberg <>
Date: Fri, 5 Oct 2012 23:27:29 +0200 (CEST)

On Wed, 3 Oct 2012, Eric Beuque wrote:

Stop the top-posting. Stop resending the same mail.

> Hi, thank you again for your help, i tried the curl debug function but it's
> the same as the write callback, so i think there it's probably a cache in
> the TCP layer.

TCP has no "cache", but a TCP connection involves two sides and both sides
have buffers in use.

> What is surprising me, as i told, is that when i shutdown my server, libcurl
> goes to the write data callback around 6-7 frame (so 6-7 second). How can we
> explain that libcurl still receive data while the connection with the server
> is closed?

When the server closes the connection the data is probably forced out. Fire up
wireshark and look at the traffic and you can see for yourself!

List admin:
Received on 2012-10-05