Subject: Re: ssh protocol flow diagram

Re: ssh protocol flow diagram

From: Daniel Stenberg <>
Date: Sat, 9 Apr 2011 10:38:29 +0200 (CEST)

On Sat, 9 Apr 2011, suyog jadhav wrote:

> I am trying to develop an ssh/scp client using libssh2. I would like to know
> if there are any flow diagram available for ssh protocol.


While such a flow diagram would be awesome, I don't think an application that
uses libssh2 will or should need any such. We provide and document an API to
use and that's what should be described and understood.

The SSH protocol details underneath should be more left for those of us who
acutally fiddles with libssh2 itself.

> I am facing specific trouble while sending file via scp, due to the EOF
> dilemma,as even though the file is sent to the remote host,and size is shown
> correct, the checksum doesn't match.

Did you follow an example? Or can you even show us your code that uses

> When libssh2_channel_write returns 0, what does it mean and how to handle it.

It means that no payload data was sent and you should keep sending. Is this
with the API in blocking or non-blocking mode?

Received on 2011-04-09