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Disk eXPress for Creating Diskette Images DXP Version 2.00 05/19/92 TABLE OF CONTENTS _________________________________________________________________ 1.0. INTRODUCTION TO Disk eXPress ........................3 1.1. What is Disk eXPress? ..........................3 1.2. Features of Disk eXPress .......................3 1.2. New features in Disk eXPress Version 2 .........4 1.4. New Disk eXPress companion program: Xtract .....4 2.0. SYSTEM REQUIREMENTS .................................5 3.0. COPYRIGHT NOTICE ....................................5 4.0. WARRANTY ............................................5 5.0. COST OF Disk eXPress ................................6 6.0. CONTENTS OF THIS PACKAGE ............................6 7.0. SYNTAX ..............................................7 7.1. Quick start ....................................7 7.2. Disk eXPress and Xtract help screens ...........8 8.0. COMMAND LINE SWITCHES DESCRIPTION ...................10 8.1. Regular mode ...................................10 8.2. Extract mode ...................................11 8.3. Batch mode support .............................12 8.4. Disk eXPress real-time bar graph display .......12 9.0. EXAMPLES ............................................13 9.1. Example 1 ......................................13 9.2. Example 2 ......................................14 9.3. Example 3 ......................................14 9.4. Example 4 ......................................15 9.5. Example 5 ......................................15 9.6. Example 6 ......................................16 9.7. Example 7 ......................................16 10.0. ERROR MESSAGES .....................................18 11.0. LIMITATIONS ........................................20 2 1.0. INTRODUCTION TO Disk eXPress _________________________________________________________________ 1.1. What is Disk eXPress? Disk eXPress (DXP) allows a diskette image to be created for electronic transmission. Think of it as a way for preparing a diskette to be FAXed like a regular document. Once the diskette image is created, it can be transmitted with the use of a modem on regular phone line, or any other electronic networks. One area of use is to archive diskette images on hard drives or tapes. This can be useful for companies maintaining an electronic bulletin board service for clients, in which diskette images for the latest hardware drivers, or fixes are available for download. This gaurantees the contents of the diskette to be the same as the original -- including all directory structures, date and time stamps of all the files and directories, and the location of any hidden information. For simple file archival purpose, the use of Disk eXPress should be avoided. The user is recommended to use one of the many fine archive programs available on the market. Disk eXPress is useful for archiving bootable diskettes, diskettes containing hidden information, or files and directory entries containing characters unrecognizable by the usual file system functions. Unlike a file archive program, Disk eXPress requires a diskette drive and a diskette in order to restore any information stored in an image. 1.2. Features of Disk eXPress - Disk eXPress recognizes all standard DOS formatted diskettes, this includes 160K, 180K, 320K, 360K, 720K, 1.2M, 1.44M, and the latest 2.88M diskettes. Any internal or external diskette drives via DOS or OS/2 block device drivers are recognized (ie: diskette drives accessed via DRIVER.SYS, $FDD5.SYS, etc.) All information on the diskette is saved to a file for electronic transmission, no information is lost! (see /a switch for detail). - Disk eXPress can be used for diskette conversion. For example, a 360K diskette image can be restored onto a 720K, 1.44M, or 2.88M diskette. If someone sends you a bootable 360K diskette image, you can restore it onto a 720K diskette, and the resulting diskette will be bootable. - Advanced virus protection. Disk eXPress detects illegal program modifications whether it's by virus, or bad electronic transmissions. - Multiple 32-bit CRC data protection. The image is protected by several 32-bit CRCs. In some cases, if a certain part of the image is modified, the resulting diskette can still be usable. 3 - Upgradability of self-extract code. Disk eXPress provides a means to upgrade the self-extract code within the image file for bug fixes, and future code enhancements upgrade. (note: version 2 image is not compatible with version 1. Replacement of version 1 self-extract code is not allowed.) 1.2. New features in Disk eXPress Version 2 - Disk eXPress is now a dual mode executable file. It runs under both OS/2 and DOS. There is only one version of the executable as opposed to two in the previous release. - Disk eXPress exploits the multi-threading capability when it is run under OS/2. It performs simultaneous disk I/O and data compression. This typically gives 10 to 50% speed up compare to running it under DOS. - Disk eXPress supports long filename for diskette images created under OS/2 with HPFS (High Performance File System) disk partition. - New data compression algorithm based on a modified Lempel-Ziv- Huffman method. Disk eXPress now compresses smaller than version 1, and is also 2 to 3 times faster. The compression rate is comparable to most file archive programs. Compression is dynamic -- non-compressible data is simply stored. - Real-time bar graph display showing current compression rate, disk read/write and compression activities (this capability is limited under DOS). - Self-extract diskette image is also a dual mode executable. /DOS and /OS2 switches are no longer required (please refer to version 1 documentation). All the extra functions are removed, and are now built-into the extract mode of Disk eXPress itself. - Disk eXPress can now produce non-self-extract image (pure image data). This is useful for diskette archival purpose on hard drive or tape. - Diskette decompression code is now built-into Disk eXPress. This can be used to decompress version 2 pure diskette image or any version 1 or 2 self-extract images. It has the full set of options, including diskette formatting, conversion, and verification. The decompressor is also fully multi-threaded under OS/2 to yield the fastest decompression time. - A new switch (/t) is added to all the decompressors so that the integrity of the image can be tested before committing the lengthy diskette write process. 1.4. New Disk eXPress companion program: Xtract - Xtract is a dual mode executable. It features all the decompression capability of Disk eXPress, including multi- threading under OS/2. 4 - It is used when distributing pure diskette images in which licensing is not required for redistributing Xtract itself. 2.0. SYSTEM REQUIREMENTS _________________________________________________________________ IBM PC, PC-AT, PS/1, PS/2 and 100% compatibles. Minimum 256K conventional memory. MS-DOS or PC-DOS version 3.00 for Disk eXPress (DOS version 3.20 is required for running self-extract images produced by Disk eXPress). OS/2 1.2 and above (including OS/2 Version 2) is required under OS/2. Hard disk is required for storing large image file. User must also provide the necessary program(s) for sending diskette image files through telephone network with the use of a modem, and whatever is necessary with any other electronic networks. 3.0. COPYRIGHT NOTICE _________________________________________________________________ DXP (Disk eXPress) Version 2.00 05/19/92 XTRACT (Xtract) Version 2.00 05/19/92 Copyright (c) 1991-92 by Albert J. Shan All Rights Reserved. No part of this program can be disassembled, modified or altered by any means. 4.0. WARRANTY _________________________________________________________________ I, Albert J. Shan, make no warranties, expressed or implied, including, but not limited to, merchantability or fitness for any particular purpose. In no event shall Albert J. Shan be liable for indirect or consequential damages arising from the use of the software program. You are free to redistribute this shareware package in its entirety. No part of this package may be included as part of a commercial package. If you have any questions about commercial distribution of Disk eXPress, I can be contacted at: Albert J. Shan 866 Citadel Drive Port Coquitlam, British Columbia CANADA V3C 5Y1 or via CompuServe, ID 70730,401 5 5.0. COST OF Disk eXPress _________________________________________________________________ Disk eXPress Version 1 was labeled as "beggarware" in which user is not required to pay a fee. Due to all the effort and time I put in for Version 2, it is now marketed as shareware. The user is granted a 30 days trial period, after which he or she is required to register the product. The cost of a single machine license is $24 Canadian. Unlimited distribution right of Xtract is granted upon licensing Disk eXPress. Please refer to the file ORDER.FRM for details. 6.0. CONTENTS OF THIS PACKAGE _________________________________________________________________ The following files are included in this package: DXP.EXE - Disk eXPress executable XTRACT.EXE - Standalone Disk eXPress image decoder (not included in the shareware version) DXP.DOC - This documentation DXP.HST - History file ORDER.FRM - Order form 6 7.0. SYNTAX _________________________________________________________________ 7.1. Quick start The synatx of Disk eXPress is very similar to the COPY command. To create a diskette image, type: dxp drive: filename To create a diskette from an image file, type: dxp filename drive: For example, to create a diskette image from your drive B:, simply type: dxp b: my_image The file "my_image.exe" will be created after Disk eXPress is finished. You can specify any combination of command switches anywhere on the command line. Spaces between command line switches are not required. By default, the file extension is ".EXE" regardless of what user specifies. When creating a pure diskette image with the /i switch, user is free to choose the file extension. For consistency, the recommended file extension to use is ".DXP". For example, under OS/2 with HPFS drive, a pure diskette image can be created as follows: dxp a: "This is diskette 3 of 5.DXP" /i You may also stop Disk eXPress at any time by pressing Ctrl-C or Ctrl-Break. The BREAK ON/OFF setting under DOS is ignored. If Disk eXPress encounters any cluster marked as bad in the File Allocation Table, you may receive a warning: X bad cluster(s) detected. Bad clusters may not be reliably read by Disk eXPress! However, if you do not encounter any 'Abort/Retry?' message during read, the image should be fine. (Note: Disk eXPress will by-pass FAT scanning if the /a switch is specified.) 7 7.2. Disk eXPress and Xtract help screens Type DXP at the OS/2 or DOS prompt to receive this help screen: Disk eXPress (OS/2 and DOS) Version 2.00 05/19/92 Created by Albert J. Shan Copyright (c) 1991-92 Regular mode: DXP [options] [drive:] [d:][path]filename [options] /? Display extract mode help screen /a Read the entire disk (all sectors) /d Input diskette image description (5 lines max.) /i Output just the diskette image /n Disable data compression /s Suppress overwrite prompt and self-check message drive Drive letter of a valid floppy drive [d:][path]filename Name of output file Valid options with only filename specified: /d Display description in image file /e Edit description in image file /r Replace or add extract code to image file Note: Items enclosed in [] are optional. Diskette must not contain any unreadable sectors. Supported formats: 160K, 180K, 320K, 360K, 1.2M, 720K, 1.44M and 2.88M DOS diskettes. Type DXP /?, and you'll get the help screen for the extract mode: Disk eXPress (OS/2 and DOS) Version 2.00 05/19/92 *** Type DXP by itself to see the regular mode help screen *** Extract mode: DXP [options] [d:][path]filename [drive:] [options] /t Test image integrity only /d Display description in image file /f Format destination diskette /s Suppress overwrite prompt and self-check message /v Verify ON (system verify plus read and compare) /c Convert image onto a higher density diskette (Target diskette must be pre-formatted, and of different form factor. It also overrides /f) [d:][path]filename Name of input file drive Drive letter of a valid floppy drive Note: Items enclosed in [] are optional. The target diskette must be free of defects (no bad sectors). Supported formats: 160K, 180K, 320K, 360K, 1.2M, 720K, 1.44M and 2.88M DOS diskettes. 8 Type XTRACT and you'll see the following help screen: Xtract (OS/2 and DOS) Version 2.00 05/19/92 Created by Albert J. Shan Copyright (c) 1991-92 Usage: XTRACT [options] [d:][path]filename [drive:] [options] /t Test image integrity only /d Display description in image file /f Format destination diskette /s Suppress overwrite warning/self-check prompt /v Verify ON (system verify plus read and compare) /c Convert image onto a higher density diskette (Target diskette must be pre-formatted, and of different form factor. It also overrides /f) [d:][path]filename Name of input file drive Drive letter of a valid floppy disk drive Note: The target diskette must be free of defects (no bad sectors). Supported formats: 160K, 180K, 320K, 360K, 1.2M, 720K, 1.44M and 2.88M DOS diskettes. 9 8.0. COMMAND LINE SWITCHES DESCRIPTION _________________________________________________________________ When Disk eXPress is used under regular mode for making diskette images, the following switches are available: 8.1. Regular mode /a By default, Disk eXPress reads up to the last allocated sector, according to the information it finds in the File Allocation Table (FAT). If there is any deleted files at the end of FAT that you may want to recover later, the default action will prevent you from a successful file recovery. Use /a to ask Disk eXPress to save all disk sectors to the image file. /d Prompt user to input description for the diskette image. A maximum of 5 lines of 40 characters each can be stored. /i Create a pure diskette image file. The self-extract code will not be bundled with the resulting file. Disk eXPress does not enforce any file extension for pure diskette image. For consistency, it is recommended to use ".DXP" as file extension. Without specifying this switch, the default file extension will be ".EXE". /n Disable compression. If the contents of the diskette is highly compressed, Disk eXPress may not succeed in compressing the data any further. This can be visually inspected when Disk eXPress is ran the first time without the /n switch. If the real-time compression rate is very low (close to 0%), the supression of compression is recommended. /s Diable any overwrite (y/N) prompt and Disk eXPress self-check message. Three switches are available when no drive letter is specified in regular mode: /d Display the description of the image file. The full path to the diskette image must be specified. /e Edit the description stored in an image file. This is used to correct the description later instead of having to redo the entire image from scratch. /r Replace or add extract code to image file. Full path and complete filename must be specified. If /r is used against a self-extract diskette image, the self-extract code will be replaced with the one stored with Disk eXPress. No backup file is created if the operation is successful. If used against a pure image file, the self-extract code will be 10 added, and a new file with ".EXE" extension will be created. The ".EXE" file created by this switch is stored in the same location of the original image file. Note: The file extension replacement algorithm simply removes any file extension starting after the last '.' and then appending "EXE". Since it is possible to use multiple '.' under HPFS, the text after the last '.' is discarded. It is advisible to avoid using multiple '.' with HPFS filename, and use a space instead. 8.2. Extract mode Disk eXPress can decode and extract 3 types of images: type 0 (non-compressed), type 1 (Version 1 compression), and type 2 (Version 2 compression). When Disk eXPress is used for extracting an image file, the image file can be a pure image file, or a self-extracting executable. The full path to the image file must be specified. Wild cards are not allowed. All the switches available in the extract mode of Disk eXPress are identical to the standanlone Xtract program. /t Test the integrity of the image only. Disk eXPress performs data decompression (if necessary) and run through a 32-bit CRC computation on the data stored in the image. It reports the stored and computed CRC values. If these values do not agree, the image will be bad. It overrides the specification of drive letter, /f, /s, /v, and the /c switch. /d Display the description of the image file. The full path to the diskette image must be specified. /f Format the destination diskette. Only standard DOS formats are supported. /s Diable any overwrite (y/N) prompt and Disk eXPress self-check message. /v Verify on. It performs a track verify via operating system call, followed by a track read, and a byte by byte comparison. The byte by byte comparison is added as an extra protection should the CRC test of track verify failed to pick up an error. If disk cache is used, the byte comparison test may not be vaild due to the fact that the cache is supplying the data, with no actual read performed. /c Convert the image onto a higher density diskette. The target diskette must be of different form factor (3.5" to 5.25" and vice versa, but not 3.5" 720K to 3.5" 1.44M). It requires a formatted diskette, and will automatically overrides the /f switch. 11 Here is a list of all diskette conversion possibilities: 160K/180K/320K/360K to 720K/1.44M/2.88M 720K to 1.2M 1.2M to 1.44M/2.88M 8.3. Batch mode support You can use Disk eXPress, Xtract, and self-extract images in a batch file (.CMD files under OS/2 and .BAT files under DOS). The return code returned by these programs are currently limited to either a 0 or 1. A return code of 0 indicates operation is successful. All display output is sent to stdout, and can be redirected to a file (Note: error output is currently sent to stdout, not stderr). 8.4. Disk eXPress real-time bar graph display One of the new features of Disk eXPress Version 2 is the use of a real-time bar graph display. Disk eXPress and Xtract will exercise the multi-threading capability under OS/2, and you'll see a display similar to the following: 3% 25% 50% 75% 100% Action Rate Track Head ├────────┼─────────┼─────────┼─────────┤ COMPRESS 52% 37 1 █████████████████▓▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▒ The above bar graph depicts 3 concurrent threads: ▒ Read thread. Performs continous reading of diskette (or disk file if it is in extract mode), and releases the diskette drive (or disk file) for use by another process when reading is finished. ▓ Compression/decompression thread. Compression/decompression is performed as soon as data is available from the read thread. █ Write thread. Compressed data is written to a disk file (or decompressed data written to diskette in extract mode). This can be another diskette drive or any block device. The description under "Action" shows what thread has just started executing. The number under "Rate" shows the current compression rate. It is the percentage reduction with respect to the size of the original data. The numbers under "Track" and "Head" show the current disk track and head where operation is being performed. 12 Since DOS only has one thread of execution, only one bar is updated at any time. Read/Compress/Decompress/Write occurs sequentially. 9.0. EXAMPLES _________________________________________________________________ 9.1. Example 1 To pack a 360K diskette in drive B: onto a file called 'disk1' for modem transmission, you type: dxp b: e:\upload\disk1 By default, Disk eXPress will automatically append ".EXE" onto the output file name. If you specify something else as file extension, it will be removeded before appending. If the command line syntax is correct, Disk eXPress will first run a self-check for virus/modification, then it will proceed to create the diskette image. You'll receive a screen similar to the following after Disk eXPress is finished: Checking Disk eXPress for modifications ... OK. 360K diskette found in drive B: File Allocation Table statistics: Track 33 head 1 contains the last allocated sector, sector 609. 3% 25% 50% 75% 100% Action Rate Track Head ├────────┼─────────┼─────────┼─────────┤ STORE 28% 33 1 ████████████████████████████████████████ 32-bit CRC of diskette image is DB49A615 By default, Disk eXPress will analyze the FAT and save up to the last sector used on the diskette. In the above example, it stops at track 33, head 1, because sector 609 is the last allocated sector. If you have a fragmented diskette, you might receive a screen similar to the following when you run Disk eXPress: Checking Disk eXPress for modifications ... OK. 1.44M diskette found in drive A: File Allocation Table statistics: Track 36 head 1 contains the last allocated sector, sector 1319. Disk fragmentation detected: 814 unallocated sectors will be saved in image (61% of total used sectors). 13 The diskette requires compression for maximum storage efficiency. 3% 25% 50% 75% 100% Action Rate Track Head ├────────┼─────────┼─────────┼─────────┤ COMPRESS 48% 16 0 ██████▓▓▒▒▒▒▒▒▒ etc. Running a disk optimization utility on the diskette will help packing files tightly together for maximum storage efficiency. Alternatively, you can copy all the files to another freshly formatted diskette so that the files are packed next to each other. 9.2. Example 2 To save the entire diskette from drive A: (including all the unused sectors) into the image with compression turned off, you type: dxp /a /n a: e:\upload\disk1 You will see this warning if the file exists: Checking Disk eXPress for modifications ... OK. E:\UPLOAD\DISK1.EXE exists, overwrite? (y/N): Default action is 'No' for pressing the 'Enter' key. Type 'y' then 'Enter' to overwrite. To suppress the warning, specify /s on the command line: dxp /a /n a: e:\upload\disk1 /s Notice that you can specify switches anywhere you want on the command line, Disk eXPress will sort them out for you. 9.3. Example 3 To enter a description when creating an image, you type: dxp b: test15 /s /d You'll see: Checking Disk eXPress for modifications ... OK. Please enter diskette description: (5 lines max.) ┌────────────────────────────────────────┐ 1: 14 You're then prompted to enter a maximum of five lines of description (40 characters for each line). To enter a blank line, just press Enter. To continue our example, type in the following: Please enter diskette description: (5 lines max.) ┌────────────────────────────────────────┐ 1: Joe, 2: This is the latest beta release of Space 3: Commander. Try it out without a joy 4: stick and let me know how it goes. 5: Regards, John 360K diskette found in drive B: File Allocation Table statistics: Track 33 head 1 contains the last allocated sector, sector 609. 3% 25% 50% 75% 100% Action Rate Track Head ├────────┼─────────┼─────────┼─────────┤ STORE 28% 16 1 ███████████████████▓▓▒▒▒▒▒▒▒ etc. 9.4. Example 4 To change the description of the diskette image produced in the last example, type: dxp e:\upload\test15.exe /e The /e switch allows description in the image file to be edited. Note: The /r switch (self-extract code replacement) can also be specified together with the /e switch. 9.5. Example 5 Now that you have the self-extract image, what are you going to do with it? Simply run it! To unpack the disk image created in example 3, type 'test15' to see the help screen: Disk eXPress Self-Extract Diskette Image (OS/2 and DOS) Version 2.00 05/19/92 Copyright (c) 1991-92 Usage: TEST15 [/t] [drive:] /t Test image integrity only drive Drive letter of a valid floppy disk drive 15 Note: The target diskette must be formatted and must not have any bad sectors. To finish our example, now type: test15 b: You'll see: ┌────── Diskette Image Description ──────┐ Joe, This is the latest beta release of Space Commander. Try it out without a joy stick and let me know how it goes. Regards, John └────────────────────────────────────────┘ 360K diskette image stored in file. Diskette in drive B: is about to be overwritten with new information. Do you wish to continue? (y/N) Default action is 'No' for pressing the 'Enter' key. Press 'y' then 'Enter' to start diskette image extraction. 9.6. Example 6 To test the integrity of the diskette image without writing out to the diskette, simply type: test15 /t And you'll see: ┌────── Diskette Image Description ──────┐ Joe, This is the latest beta release of Space Commander. Try it out without a joy stick and let me know how it goes. Regards, John └────────────────────────────────────────┘ 360K diskette image stored in file. 100% Read 32-bit CRC stored: DB49A615 32-bit CRC computed: DB49A615 Note: /t overrides drive letter specified on the command line. 16 9.7. Example 7 Now that Joe got the diskette image. He doesn't have a 360K or 1.2M drive (5.25" drive). All he has is a 1.44M 3.5" drive. He also happens to have a spare 720K (low-density) diskette he can use. What can he do? He can use the /c switch in the extract mode of Disk eXPress or Xtract. The /c switch can be used to convert the diskette image from 360K to 720K, and all the data will still be intact, and usable. The diskette used for conversion must be pre-formatted. So, Joe went ahead and formatted the diskette as a 720K diskette, and he typed: dxp test15.exe a: /c And receives the following screen (answer y at the prompt): Checking Disk eXPress for modifications ... OK. Checking test15.EXE for modifications ... OK. 360K diskette image (Disk eXPress type 2) Diskette in drive A: is about to be overwritten with new information. Do you wish to continue? (y/N) y 720K diskette found in drive A: Converting 360K image onto 720K diskette ... 3% 25% 50% 75% 100% Action Track Head ├────────┼─────────┼─────────┼─────────┤ DECOMPRESS 20 0 █████████▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ etc. 17 10.0. ERROR MESSAGES _________________________________________________________________ Disk eXPress incorporates 32-bit CRC checking for itself and the image it produces. In the event of a virus infection or other means of modifications (such as errors in electronic transmissions), the program will abort, and the following message is displayed: *** File has been modified or not a valid image file. Here is a run down of major error messages produced by Disk eXPress, Xtract and self-extract images: (a beep followed by one of the following messages) > For bad or not properly formatted diskette during read, write, format or verify: *** Read Error: Abort, Retry? (a/R): *** Write Error: Abort, Retry? (a/R): *** Format Error: Abort, Retry? (a/R): *** Verify Error: Abort, Retry? (a/R): *** Bad CRC. *** Sector not found. *** General failure reading drive X: *** Unknown media/inconsistent boot record. > When disk is full during image creation (output will be deleted): *** Error writing disk or disk full. > With a write protected diskette during diskette write: *** Diskette is write protected. > When replacing self-extract code in images with a lower revision level of Disk eXPress: *** Image was created by Disk eXPress x.xx which is of higher revision level. > When diskette drive is not ready: *** Drive X: not ready. 18 > When drive specified is not available or not a diskette drive: *** Invalid drive specified. *** Drive X: is not a floppy drive. > When attempting to replace a version 1 self-extract header with version 2 by the /r switch: *** filename is not a type 2 image. > When Disk eXPress or Xtract is asked to extract an unrecognized image file: *** File has been modified or not a valid image file. > When Disk eXPress or Xtract is asked to convert a diskette image to the same form factor diskette: *** Conversion not supported on target diskette. > Some error messages returned by Disk eXPress are displayed as: *** Error n, Drive X: In such event, please document the procedure on how to get to the above error, and contact me as soon as possible. 19 11.0. LIMITATIONS _________________________________________________________________ When Disk eXPress is used to produce a self-extract diskette image, the extract code is bundled as an overhead for each image produced. The overhead is currently at 25K. This is acceptable, considering the size of any non-trivial diskette image is usually quite large (in the order of several hundred kilo bytes or even mega bytes). 25K should require no more that two minutes for a 2400 baud modem to transfer, and with a 14.4K V.32bis modem, the overhead is less than 16 seconds. Other limitations include the inability to read a diskette drive over the LAN (limitation of the network driver), and Disk eXPress over any copy protected programs. Another limitation is its inability to read over physically bad sectors. Any suggestions and comments are welcome. Suggestions for new features may eventually be incorporated into a future release. Currently on the draw board includes the 32-bit version for OS/2 2.0, and the possibility of making it into a multi-threaded PM application with the use of System Object Model (SOM). 20