From owner-freebsd-hackers Wed Nov 8 15:42:00 1995 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id PAA28368 for hackers-outgoing; Wed, 8 Nov 1995 15:42:00 -0800 Received: from irz301.inf.tu-dresden.de (irz301.inf.tu-dresden.de [141.76.1.11]) by freefall.freebsd.org (8.6.12/8.6.6) with ESMTP id PAA28361 for ; Wed, 8 Nov 1995 15:41:51 -0800 Received: from sax.sax.de by irz301.inf.tu-dresden.de (8.6.12/8.6.12-s1) with ESMTP id AAA24738; Thu, 9 Nov 1995 00:41:40 +0100 Received: by sax.sax.de (8.6.11/8.6.12-s1) with UUCP id AAA26635; Thu, 9 Nov 1995 00:41:39 +0100 Received: (from j@localhost) by uriah.heep.sax.de (8.6.12/8.6.9) id XAA10849; Wed, 8 Nov 1995 23:21:01 +0100 From: J Wunsch Message-Id: <199511082221.XAA10849@uriah.heep.sax.de> Subject: Re: ioctl() question... To: msmith@atrad.adelaide.edu.au (Michael Smith) Date: Wed, 8 Nov 1995 23:21:01 +0100 (MET) Cc: freebsd-hackers@freebsd.org (FreeBSD hackers) Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) In-Reply-To: <199511080922.JAA06752@genesis.atrad.adelaide.edu.au> from "Michael Smith" at Nov 8, 95 09:22:39 am X-Phone: +49-351-2012 669 X-Mailer: ELM [version 2.4 PL23] MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Content-Length: 651 Sender: owner-hackers@freebsd.org Precedence: bulk As Michael Smith wrote: > > > Yup, but what's the question? > > Ah, sorry. The question was : > > is it faster/better/more traditional/sexier to - > > a) use the two-ioctl sequence _IOW(lots), IOR(int) > > or > > b) use a single ioctl _IOWR(lots) > > where bulk data is passed in, but only an int is coming back. You might find examples for both. The split version might be slightly faster, but unless you're going to call it 10000 times a second, i doubt one would notice it. -- cheers, J"org joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE Never trust an operating system you don't have sources for. ;-)