Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!uwmcsd1!marque!uunet!super!rminnich
From: rminnich@super.ORG (Ronald G Minnich)
Newsgroups: comp.unix.wizards
Subject: Re: How can I read keyboard without stopping
Keywords: curses keyboard
Message-ID: <669@super.ORG>
Date: 29 Aug 88 17:52:08 GMT
References: <813@ms3.UUCP> <1246@mcgill-vision.UUCP> <1988Aug15.130550.8571@ateng.uucp> <1267@ficc.UUCP>
Sender: uucp@super.ORG
Reply-To: rminnich@metropolis.UUCP (Ronald G Minnich)
Organization: Supercomputing Research Center, Lanham, MD
Lines: 18

In article <1267@ficc.UUCP> peter@ficc.UUCP (Peter da Silva) writes:
>I believe that once upon a time on some system a stat() on a pipe would
>return the number of characters in a pipe. Wouldn't it make sense to
>have stat() on a terminal device return the number of characters available?
You would think so, wouldn't you. 
On most of the systems i have tried it on it 
always returns 0 on ttys. 
That seems quite wrong to me, but there you are. 
Also, on most unix's you can't tell whether there are 0 bytes
to read because of an eof or 0 bytes cause nothing is there yet. 
I haven't looked lately to see if such a thing has been added; on 4.2-like
systems you had to to shenanigans with select() and FIONREAD to determine
that you were at EOF. And then you had to try to read 1 byte
to get the rest of the kernel to realize you really WERE
at EOF. Annoying. So many other OSs have a way of just TELLING you 
you are at EOF with a simple function call.
There are funny little holes in the Unix filesystem even now ...
ron