iHPFS An HPFS Driver for DOS Copyright (C) 1993-1997 Marcus Better Version 1.24 June 1, 1997 Overview ======== iHPFS makes it possible for OS/2 users to use their HPFS partitions when they boot plain DOS. The HPFS partition is assigned a drive letter, and can be accessed like any DOS drive. iHPFS is restricted to read-only access. iHPFS is easy to install and convenient to use, as it acts like any DOS drive. Data files and programs on the HPFS partition may be read and executed, or copied to other drives. License ======= iHPFS is free software, and is distributed under the GNU General Public License. Please see the file COPYING for details. System requirements =================== In order to run iHPFS, you need - a 386 processor or better - MS-DOS or PC DOS version 3.10 or later, DR DOS version 5 or 6, or Novell DOS version 7. It is also nice if you have an HPFS partition, otherwise all you will get from iHPFS is an error message. How to use iHPFS ================ Run IHPFS.EXE from the DOS prompt. The syntax is: IHPFS [options] [d:n d:n ...] or IHPFS /U [d:] The brackets indicate an optional parameter. d: The drive letter that you want to assign to an iHPFS drive. You may specify more than one drive letter on the same command line. If no drive letters are specified, iHPFS will scan your hard drives and automatically install all HPFS partitions. n The number of the HPFS partition that you want to access. HPFS partitions are numbered (logically) so that you can specify to iHPFS which partitions you want to access. The first HPFS partition on the first hard disk is partition number 1. Note that only HPFS partitions are counted - if your system has two HPFS partitions, they will have numbers 1 and 2, regardless of any other non-HPFS partitions you might have. iHPFS recognizes the following options: /B Make use of certain BIOS extensions to access large IDE drives. Please read the section below on ”Large IDE Drives” before using this option. /C=x Set up a cache in XMS memory. A cache can improve performance tremendously. x specifies the cache size, in KB, and is not optional. To use this option, you must have an XMS driver like HIMEM.SYS loaded. /L This option makes it possible to access files with long filenames. These files will be given a new filename and extension. The new name will consist of the first valid characters (eight or less) before the first dot in the long filename. The extension is computed from the long filename, and is made up of letters, digits and a few other characters. Filenames that begin with a dot will be seen as HPFS.xxx, where xxx is the computed extension. /M Disables multitrack operations. When this option is given, iHPFS will not perform BIOS calls that read sectors from several tracks at once. This option may be necessary if your BIOS cannot handle multitrack operations, and should only be used if iHPFS does not work otherwise. /U Uninstalls one or more iHPFS drives. If no drive letter is specified, this will uninstall all iHPFS drives, and remove the driver from memory. If a drive letter is specified, only that drive will be removed. If another TSR has been loaded after iHPFS, it may not be possible to uninstall iHPFS comletely in a safe way. In those cases, a few bytes of iHPFS' code will remain resident, although inactive. Examples -------- To install iHPFS for all HPFS partitions, type IHPFS To install iHPFS for all HPFS partitions with long filename support and a 128KB cache, type IHPFS /L /C=128 To install only HPFS partition 2 as G:, type IHPFS G:2 To remove iHPFS drive G:, type IHPFS /U G: To uninstall iHPFS completely, type IHPFS /U Large IDE drives ================ There is a problem with accessing IDE (ATA) drives larger than 528MB (528 million bytes). The problem arises on some configurations when a partition occupies any cylinders numbered 1024 or higher. iHPFS can access these partitions if the BIOS supports it. If iHPFS cannot access some of your HPFS partitions, you can try to run iHPFS with the /B option. This tells iHPFS to use a certain BIOS extension which is present on many BIOSes. However, if this extension is not supported by your BIOS, this may cause problems. That is why the /B option is required to enable the use of the extension. If the /B option causes troubles, then simply refrain from using it. In particular, the /B option may not work with Windows 95. If some of your partitions cannot be accessed because the BIOS support is missing, there are a few possible remedies. The solution can be to obtain a newer BIOS from the manufacturer. In some cases, a software driver for the EIDE card can be used. It might also be tempting to experiment with various BIOS configuration settings. However, this can cause the sectors on the disk to be shuffled like a deck of cards, resulting in loss of data. Be sure to backup first. The future of iHPFS =================== Many users have asked if there is going to be a read-write version of iHPFS. I have decided not to make such a version. The primary reason is lack of time. Another reason is that I think it would very unsafe to run such a program from DOS, because the risk of data loss in the event of a crash is too large. Please do not write to me to complain about this. I do not plan to add any new features to the program, but will attempt to fix any remaining bugs and problems. If you make any modifications to the program, you are welcome to send them to me for inclusion. Contacting the author ===================== You are welcome to send me any ideas, comments and suggestions for iHPFS. If you have found any bugs, please let me know. My email address is Marcus.Better@abc.se The latest version of iHPFS is available at http://www.student.nada.kth.se/~f96-bet/ihpfs/