From: "Matthias Paul" Organization: Rechenzentrum RWTH Aachen To: opendos AT delorie DOT com Date: Tue, 14 Mar 2000 17:05:43 +0100 Subject: Re: Dual boot DR DOS and Win95 X-mailer: Pegasus Mail v3.22 Message-ID: <484DA0D0BC1@reze-1.rz.rwth-aachen.de> Reply-To: opendos AT delorie DOT com On Thu, 09 Mar 2000 19:55:43 Charles Dye wrote: > Here's how I set up my system at work: > > 1) Boot from an MS-DOS 5 or 6 floppy. Create boot partition using > FDISK. Reboot and format it. Use MS-DOS 5 or 6 because the Win95 > FDISK can create partitions which DR DOS can't access (yes, even > FAT16) and the DR DOS version of FDISK is just plain buggy. BTW, these problems are long fixed with my personal issues of FDISK, FORMAT, and SYS. It is actually nothing more than switching back the OEM label xxxxxyyy to "IBM 3.3" instead of "DRDOS 7". Of course, you can do the same using DISKEDIT or DEBUG. This also fixes serious OS/2 problems to access DR-DOS partitions. As far as I have tracked this down, the problem was not the xxxxx string like "MSDOS" "MSWIN" "IBM " or "DIGITAL" or "DRDOS", but the yyy number (usually in the format y.y). MS-DOS, PC DOS and OS/2 use it to switch between various forms of historic usages of the entries in the BPB table at the beginning of the boot sector. For compatibility with Compaq DOS 3.31 and older issues of DR DOS, DR-DOS 7 still uses the entry for hidden sectors as an absolute value, while (at least for logical drives in an extended partition) it is used relative to the current partition by recent issues of MS-DOS etc. (usually 3Fh always on current harddisks). Changing the version number in the OEM label to anything but "3.3" will since break OS/2 (and under some conditions also MS-DOS/PC-DOS). However, it s not as easy as just changing the boot sector setup, because the cause for the incompatiblity is not the FORMAT, SYS, or FDISK utility, but an Generic IOCTL function they use to retrieve that value. Changing this there would break all older issues of these utilities, which could malfunction when run on current issues of the OS. So, it s best to just stick with "IBM 3.3" for now... > 2) Install Windows 95 normally. Configure it however you like. You > can use FDISK to create more volumes, but some of them may not be > accessible to DR DOS -- FAT32 partitions definitely won't be. See my other email regarding FAT32 access under DR-DOS, although I don t count this a full solution to the problem. Matthias ------------------------------------------------------------------- Matthias Paul, Ubierstrasse 28, D-50321 Bruehl, Germany eMail: Web : http://www.rhrz.uni-bonn.de/~uzs180/mpdokeng.html -------------------------------------------------------------------