SSH clients and hiding passwords

Dear group,

This is somewhat of a general developer question in regards to SSH clients, and their functionality as far as hiding user passwords as they are typed into a terminal. For example, Putty or any other self respecting SSH client, will hide the password that a user types after entering the "su" command. I've been playing around with Tamir Gal's SharpSSH (http://www.codeproject.com/cs/internet/sharpssh.asp?df=100&forumid=225425&select=2075851#xx2075851xx) and messing around with coding my own windows SSH client. My question is, how do clients normally handle the hiding of user passwords as they are entered into the console? As far as I can tell, the SSH stream itself does not tell the client when to hide user input. Do SSH clients simply "look" for commands like "su" and "passwd", and adjust the hiding of user passwords that way?

Forgive me if this is a newbie question aboutthe SSH protocol. I've been enjoying learning more about the protocol, and I couldn't help but post a question in regards to how SSH clients handle user input passwords. Thank you for your time.

Dan
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