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Re: Pause/Continue HTTPS transfer

From: Daniel Stenberg via curl-library <>
Date: Fri, 21 Feb 2020 23:03:55 +0100 (CET)

On Fri, 21 Feb 2020, Anders Berg via curl-library wrote:

> I suspect that this failure to resume the transfer occurs when (or at least
> has something to do with) data is buffered in the SSL backend and
> select/poll will not return any events on the socket (either due to the
> server has transmitted all data for the request, or that the server can't
> send any more data due to being limited by the TCP window).

Sounds like a reasonably theory but I haven't investigated anything to say for
sure if that is truly what's going on. What curl version are you using when
you experience this?

The server used in your example code speaks HTTP/1.1, is that also the case
for your "real" case?

> Attached is a test program that hopefully demonstrates the phenomenon (at
> least it does for me ;-) Is there an issue here or have I missed something?

I'm not aware of any existing issue like this.

Can you be so kind and file this issue in the curl issue tracker on github [1]
so that we don't let this one slip?

[1] =

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Received on 2020-02-21