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Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!bunyip.cc.uq.oz.au!munnari.oz.au!ihnp4.ucsd.edu!agate!howland.reston.ans.net!vixen.cso.uiuc.edu!sdd.hp.com!hp-pcd!hp-cv!reuter.cse.ogi.edu!netnews.nwnet.net!news.u.washington.edu!tzs From: tzs@u.washington.edu (Tim Smith) Newsgroups: comp.os.386bsd.development Subject: Re: FreeBSD 2.0: someone please fix mount_pcfs Date: 19 Aug 1994 09:46:09 GMT Organization: University of Washington School of Law, Class of '95 Lines: 28 Message-ID: <331v11$kjs@news.u.washington.edu> References: <32uvui$dov@Venus.mcs.com> <331b5v$q00@u.cc.utah.edu> NNTP-Posting-Host: stein4.u.washington.edu Terry Lambert <terry@cs.weber.edu> wrote: >UnixWare, NetBSD, FreeBSD are *known* to require a partition of the >particular OS type to allow mounting. UnixWare, by default, as a >matter of record, doesn't have the ability to mount DOS file systems >without the FSK (Filesystem Survival Kit) code, which is *BSD derived. > >I suspect Linux and others also have this limiation, it's just that I >haven't checked them out for it one way or another to be able to say. I just tried it with Linux, and it works fine. My second disk contains a partition map and an HPFS partition, both created by OS/2, and a DOS partition, created by DOS. Linux has no trouble accessing the DOS partition. >The reasoning is that the DOS partition table, which you would have >to read to do the mount, barring a partition with a disklabel (or >in the UnixWare case, a Volume Table Of Contents), there is no way >to decode the C/H/S values as absolute sector offsets without a >firm grasp of the BIOS apparent geometry on a translated (ie: modern) >disk drive. I suspect SCO will fail this test on modern drives. I'm not sure I understand the problem. Why can't the OS figure out the geometry by reading the partition map? MS-DOS partitions end on cylinder boundaries, and so by looking at the partition map entry for DOS the dos partition, you can figure out the number of sectors and heads that the BIOS reported to DOS when DOS fdisk created the DOS partition. --Tim Smith