Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!husc6!necntc!ima!haddock!karl From: karl@haddock.ISC.COM (Karl Heuer) Newsgroups: comp.unix.wizards Subject: Re: Character special files cannot seek? (was Re: Seek on a pipe) Message-ID: <712@haddock.ISC.COM> Date: Fri, 10-Jul-87 20:19:08 EDT Article-I.D.: haddock.712 Posted: Fri Jul 10 20:19:08 1987 Date-Received: Sun, 12-Jul-87 12:48:57 EDT References: <7359@brl-adm.ARPA> <983@bobkat.UUCP> <5872@brl-smoke.ARPA> <1791@ttrdc.UUCP> <1088@killer.UUCP> Reply-To: karl@haddock.ISC.COM (Karl Heuer) Organization: Interactive Systems, Boston Lines: 15 In article <1088@killer.UUCP> jfh@killer.UUCP (John Haugh) writes: >I seem to recall that you can seek on [the c-special files mem, kmem, rdsk]. >I think the only things that leaves out are raw tapes and ttys. Did anyone >not really know this? When I said "character special files are not seekable in general", I did not mean to imply that all such were nonseekable, but that not all such were seekable. My article asserted that "isatty()" was not an appropriate test for seekability. The example of raw tape proves my statement. I was assuming that the canseek() function, when presented with a c-special file, should conservatively assume nonseekability. In normal usage, this is appropriate. Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint