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Re: Why SshExec close the connexion ? [message #53077 is a reply to message #53074]

Sat, 22 February 2020 11:18

Oblivion
Messages: 1093
Registered: August 2007

Senior Contributor

Hello Omari,

Quote:

but, the first use of SshExec close the session .

In SSH2 protocol, exec channels are fire-and-forget type channels - they are unique to single execution target.

The protocol does not allow the reuse of exec channels.

That's why you need to create a new SshExec instance for each command instance. (They are relatively cheap).

So what you need to do is:

        String cout, cerr;
        SshExec ExecMkDir(session);
        SshExec ExecRun(session);
	Scp scp(session);

        ExecMkDir("mkdir target/", cout, cerr);
        scp.SaveFile("target/binary", LoadFile(localFile));
        ExecRun("target/binary&", cout, cerr);

Yet, as mentioned in SSH package's docs, If you need batch operations, I'd recommend SshShell instead.

OTOH, server does not close the connection on my setups (OpenSSH/sshd). It simply fails to reuse the exec channel.
This may be due to different server implementations, I am not sure.

Now if you are talking about the session, then you have to remember that all SSH objects are scope-bound, including the session. Typical C++ rule.

Still, the output of a brief trace (Ssh::Trace()) would be more helpful.

If you have any other questions regarding SSH package, or run into any other issues, feel free to ask. Smile

Best regards,
Oblivion

Github page: https://github.com/ismail-yilmaz
upp-components: https://github.com/ismail-yilmaz/upp-components
Bobcat the terminal emulator: https://github.com/ismail-yilmaz/Bobcat

[Updated on: Sat, 22 February 2020 13:05]

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