Commands executed using JSch behaves differently than in SSH terminal (bypasses confirm prompt message of "yes/"no")

Question

Note: I log into a device, not a computer, so I login to configuration mode (instead of non configuration mode).

I am using JSch library in Java, to login with an SSH protocol. I login like this:

channel = con.openChannel("shell");
channel.connect();

In some cases, when I send through the shell a command that needs su (configuration mode) permissions (change configuration), this code bypasses the prompt confirmation message of - this may prevent other users from changing configuration. While if I enter the command manually with SSH client/terminal, I have to enter yes for confirmation.

Does anyone have any idea why?
Thanks.

[ manual shell session ]

When I log in through JSch I can do the configuration commands even, when the I don't insert "yes" to the array of commands to be executed.

this may be related:http://stackoverflow.com/questions/27634152/jsch-shellchannel-inputing-confirm-message-doesnt-work — Asaf Bartov, Feb 01 '17 at 16:51
Your edit did not clarify anything to me. Maybe a screenshot or a transcript of an interactive SSH session may clarify what you need. — Martin Prikryl, Feb 02 '17 at 10:46
Yes, but what's the problem actually? If you want to automate the command, why do you mind that you are not bothered with a confirmation prompt? — Martin Prikryl, Feb 02 '17 at 11:21
It is Ok for me (even better) that it behaves like this, but i still would prefer to understand the behaviour. in a different note, i login as "shell", not as "exec". — Asaf Bartov, Feb 02 '17 at 11:36

Martin Prikryl · Accepted Answer · 2017-06-13T10:43:18.227

By default the JSch does not request PTY (pseudo-terminal).

That can cause some commands to behave differently than in an interactive SSH terminal.

You can override this using the ChannelSession.setPty.

If the above does not help, see also similar questions:

Certain Unix commands fail with "... not found", when executed through Java using JSch
Certain Unix commands fail with "... not found", when executed through Java using JSch even with setPty enabled

Commands executed using JSch behaves differently than in SSH terminal (bypasses confirm prompt message of "yes/"no")

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