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Re: How to do optimal FTP upload for multiple files?

From: Daniel Stenberg via curl-library <>
Date: Fri, 19 Jul 2019 00:14:19 +0200 (CEST)

On Thu, 18 Jul 2019, Daniel Jeliski via curl-library wrote:

> As for the connection timeout, it appears to be a well known problem with
> FTP on slow connections with oversized buffers. I just found a 10 year old
> message describing what looks like the same problem:

I believe that's a misunderstanding.

That's a known problem with long-going FTP transfers - totally independent of
buffer size. Since FTP uses two connections, sometimes when a transfer takes
more than a certain time, a network equipment like a NAT or a firewall closes
the control connection due to inactivity before the transfer is done. But that
doesn't seem to be what Taras has described here.

Since libcurl uses non-blocking sockets internally I can't see any reason why
a larger upload buffer would cause a greater risk for any timeout. What am I

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Received on 2019-07-19