Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ncar!umigw!steve
From: steve@umigw.MIAMI.EDU (steve emmerson)
Newsgroups: comp.lang.c
Subject: Re: Getchar w/wout echo
Summary: make raw{en,dis}able idempotent?
Message-ID: <155@umigw.MIAMI.EDU>
Date: 26 Aug 88 13:11:25 GMT
References: <371@marob.MASA.COM> <225800052@uxe.cso.uiuc.edu> <65197@sun.uucp> <302@quintus.UUCP> <1988Aug23.164855.26679@utzoo.uucp> <309@ <6589@haddock.ima.isc.com>
Reply-To: steve@umigw.miami.edu (steve emmerson)
Followup-To: comp.lang.c
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Organization: University of Miami
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In article <6589@haddock.ima.isc.com> karl@haddock.isc.com (Karl Heuer) writes:
>Rawenable() and rawdisable() change the state from cooked to raw or 
>from raw to cooked, respectively; if called from the "wrong" state, 
>the behavior is undefined.

I would prefer that rawenable() and rawdisable() be idempotent* rather 
than undefined, unless, of course, this means that they can't be 
implemented on some systems.

I believe this would enable slightly cleaner programs as the relevant
state information would be contained (at least conceptually) in the
raw{en,dis}able()/getrawchar() module -- discharging the programer from
responsibility over the matter.

------------
* "idempotent" means that the effect of calling it twice is the same as 
calling it once, i.e. the second call is a functional no-op.)
-- 
Steve Emmerson                     Inet: steve@umigw.miami.edu [128.116.10.1]
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"Computers are like God in the Old Testament: lots of rules and no mercy"