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Path: sserve!newshost.anu.edu.au!munnari.oz.au!constellation!paladin.american.edu!europa.eng.gtefsd.com!uunet!Germany.EU.net!netmbx.de!zrz.TU-Berlin.DE!cs.tu-berlin.de!gmdtub!arg From: arg@first.gmd.de (Arnulf Guenther) Newsgroups: comp.os.386bsd.questions Subject: Q: programming CD audio Message-ID: <ARG.93Nov28143243@gauss.first.gmd.de> Date: 28 Nov 93 13:32:43 GMT Sender: news@bigfoot.first.gmd.de Organization: GMD-FIRST, Berlin Lines: 24 My question is: If provided with enough space the CDIOREADTOCENTRYS ioctl returns two extra bytes of information after the information for the leadout track and I want to know what those two bytes represents. My system consists of 486/AHA 1742a/Toshiba XM-3301/FreeBSD 1.0. Works just fine. Experimenting with the CD audio interface I stumbled across this thing: The CDIOREADTOCHEADER and CDIOREADTOCENTRYS ioctls are very similar--in fact they are mapped onto the same SCSI command. With CDIOREADTOCENTRYS one can obtain info about all tracks or only how many tracks are on this CD. The field length in ioc_toc_header is zero after a CDIOREADTOCHEADER ioctl or filled with a value depending of the size of the requested info after a CDIOREADTOCENTRYS ioctl. However, if I have a CD with 8 tracks (plus one leadout track) and I allocate 80 bytes because it's just a round number and also tell ioctl(CDIOREADTOCENTRYS) I have 80 bytes. The length field in the header contains the value dec. 74 and after the leadout track info are two extra bytes which I cannot relate to any info I can think of. Any Ideas? Thanx in Advance, -Arnulf --