Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!lll-winken!elroy.jpl.nasa.gov!usc!orion.oac.uci.edu!cerritos.edu!arizona.edu!arizona!dave
From: dave@cs.arizona.edu (Dave P. Schaumann)
Newsgroups: comp.lang.c
Subject: Re: getchar()
Message-ID: <1038@caslon.cs.arizona.edu>
Date: 5 Mar 91 20:11:07 GMT
References: <1991Mar5.063644.8459@cs.mcgill.ca>
Organization: U of Arizona CS Dept, Tucson
Lines: 24

In article <1991Mar5.063644.8459@cs.mcgill.ca> storm@cs.mcgill.ca (Marc WANDSCHNEIDER) writes:
>[program that reads input using getchar() deleted]
>
>   Echos every character that you put on the screen.  However, it does not 
>stop (even after a Capital A) until you hit return.

The problem with your program is that stdin (and stdout) is buffered.  This
means for input, that when you request a character, the system actually gets
a whole line, and then feeds you the result one character at a time.  This
is efficient for when the overhead on a read is high, and doesn't depend much
on the size of the input read.

That is why your program doesn't quit until you hit return; the call to
getchar() doesn't return until you  hit (carriage) return.

Your next question, no doubt is "how do I do unbuffered reads?".
Unfortunately, there is no portable way to do this, although many (most?)
systems have some way to do it.  I would suggest you RTFM to find out more.

-- 
		Dave Schaumann		dave@cs.arizona.edu
'Dog Gang'!  Where do they get off calling us the 'Dog Gang'?  I'm beginning to
think the party's over.  I'm beginning to think maybe we don't need a dog.  Or
maybe we need a *new* dog.  Or maybe we need a *cat*! - Amazing Stories