Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!amdcad!ames!umd5!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: (So-Called) ANSI C
Message-ID: <6978@brl-smoke.ARPA>
Date: 8 Jan 88 04:54:48 GMT
References: <4668@pyr.gatech.EDU> <2046@haddock.ISC.COM> <400@uniq.UUCP> <6942@brl-smoke.ARPA> <38060@sun.uucp>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 11

In article <38060@sun.uucp> guy@gorodish.Sun.COM (Guy Harris) writes:
>The trouble is that "_doscan" uses "ungetc" ...

Ah, now I see the problem.  It is the caller's buffer, not stdio's,
that is being modified.  That is clearly a bug, which is relatively
easy to fix in sscanf() by strdup()ing the caller's buffer.

This further reinforces the position that ANSI C *scanf() should not
use ungetc(), although I think the AT&T folks believe that by allowing
a couple of extra "slop space" bytes in a FILE structure's buffer they
can get away with using ungetc().  I've never been convinced of that.