.* .* $Header: D:/ext2-os2/doc/RCS/intro.im,v 1.1 1995/08/08 18:52:16 Willm Exp Willm $ .* .* Linux ext2 file system driver for OS/2 2.x and WARP - Allows OS/2 to .* access your Linux ext2fs partitions as normal drive letters. .* OS/2 implementation : Copyright (C) 1995 Matthieu WILLM .* .* This program is free software; you can redistribute it and/or modify .* it under the terms of the GNU General Public License as published by .* the Free Software Foundation; either version 2 of the License, or .* (at your option) any later version. .* .* This program is distributed in the hope that it will be useful, .* but WITHOUT ANY WARRANTY; without even the implied warranty of .* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the .* GNU General Public License for more details. .* .* You should have received a copy of the GNU General Public License .* along with this program; if not, write to the Free Software .* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. .******************************************************************************* .*** Introduction *** .******************************************************************************* :h1. Introduction :p. ext2-os2 is a file system driver for accessing Linux &EXT2FS. file systems from &OS2. 2.x and WARP. This is currently a beta version. My initial purpose was to get limited read only access to &EXT2FS. partitions from my &OS2. system, so at the beginning, it was more a quick and dirty rewrite than a clean and full port of the Linux &EXT2FS. file system kernel module. :p. Now I'm trying to improve it to reuse as much original &EXT2FS. code as possible in order to get a full featured &EXT2FS. driver on &OS2.. I'm writing a kind of IFS to VFS translation layer, and porting some Linux kernel services in order to minimize the changes required into the &EXT2FS. sources. At the moment most of the changes in &EXT2FS. are actually due to the 32 to 16 bits port (the IFS interface is still 16 bits), and the IFS code is 50% &OS2. specific (IFS to VFS translation layer, Linux kernel services) and 50% ported from Linux (ext2fs sources). My main constraint is not feasibility but ... time, so contributions will be welcome ! :p. Ext2-os2 has now read and write capabilities but please notice that it is :color fc=red bc=default.EARLY CODE :color fc=default bc=default. (cf :link reftype=hd refid=999.IMPORTANT WARNING - READ THIS FIRST:elink. ), I release it to get some feedback on how it works on other machines than mine, so don't be angry if it can't work for you now ... maybe in a future release ! :p. Writing an IFS is not a simple thing, for several reasons : first there's only one IBM document on the IFS interface, and IBM provides it 'AS IS' ... it means lots of guess ! The second one is that the IFS interface is complex (lots of stuff to support, EAS ...) and still 16 bits. For instance making the Workplace Shell survive to my IFS is a headache... The third one is that the &OS2. IFS interface is quite different from the Linux VFS interface : I had to rewrite from scratch several Linux VFS or even kernel services. The fourth thing is the fact that &OS2. is a multithreaded OS : you can be reentered for the SAME open file instance in your IFS, so locking of resources must be more strict than under Linux, not even speaking of &OS2. SMP, which I really don't support ..... so don't blame me if it doesn't work as you hoped ... I'll try to do better the next time ! :p. :color fc=red bc=default. DISCLAIMER : .br THE FACT THAT I WORK FOR IBM HAS NOTHING TO DO WITH THIS DRIVER. I'M WRITING IT AT HOME, DURING MY SPARE TIME, FOR MY OWN PURPOSES, ON MY OWN MACHINE, WITHOUT ANY IBM MEANS. I USED ONLY IBM PUBLISHED DOCUMENTS TO WRITE IT : I AM ABSOLUTELY NOT RELATED TO THE OS/2 DEVELOPMENT TEAM AND THUS I HAVE ABSOLUTELY NO ACCESS TO ANY CONFIDENTIAL OS/2 IFS RELATED INFORMATION. :color fc=default bc=default. :p. Anyway I hope you'll enjoy trying this driver, and even if I don't have much time, I'll try to keep improving it. I wait for your feedback on this version : comments, ideas, bug reports and contributions are welcome. :p.Matthieu WILLM :parml break=fit tsize=30 compact. :pt.willm@ibm.net :pd.Home :pt.mwillm@vnet.ibm.com :pd.Work :eparml. :nt. English is not my native language ... so this document isn't certainly perfect. :ent.