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Date: Sat, 17 Feb 2007 11:29:49 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Mockern@yandex.ru
CC: linux-kernel@vger.kernel.org
Subject: Re: serial or tty driver
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Mockern wrote:
> I have a question, what is really difference between serial and tty drivers?
> As I understand tty is high level and communicates with user space. 

That's pretty much it, yes.  When you're talking to a serial port, you 
have a stack that looks roughly like:

	(Userspace)
	VFS layer
	tty layer ----------------------\
	serial core layer                line discipline
	serial driver
	(Hardware)

There are other devices which can exist below the tty layer, like the 
pty driver:

	(Userspace)
	VFS layer
	tty layer ----------------------\
	pty driver                       line discipline

	-hpa