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Date: Mon, 1 Sep 1997 23:39:23 -0700 (PDT)
From: Doug White <dwhite@gdi.uoregon.edu>
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Reply-To: Doug White <dwhite@resnet.uoregon.edu>
To: Wang Huaibo <bu-fl@cs.sjtu.edu.cn>
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Subject: Re: Quesion
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On Mon, 1 Sep 1997, Wang Huaibo wrote:

> 	I wonder what's the difference between /dev/ptyXX and /dev/ttyXX
> ( appears in telnetd source file "sys_term.c" )and whether there is
> Electronic version of books about Unix design and implementation 
> downoladable from the net.

Well, /dev/ttyXX are physical devices.  You'll notice that there are
different types of tty devices, particulary ttyd* for dial-in devices and
ttyv* for virtual terminals.  You'd be more interested in the difference
between pty* and ttyp*, which is well explained in the pty(4) man page. 

For design and implementation, I don't think there's much online
documentation except what's in the man pages and in /usr/share/doc/.  

If you're interested in these topics, the book ``The Design and
Implementation of the 4.4BSD Operating System'' (aka the daemon book) is
required reading.  I forgot where, but FreeBSD users can obtain this book
cheaply through an online bookstore, check the -questions archives.

Doug White                              | University of Oregon  
Internet:  dwhite@resnet.uoregon.edu    | Residence Networking Assistant
http://gladstone.uoregon.edu/~dwhite    | Computer Science Major
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