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- ________ _______ ________
- --<__ __/-/ ____/-<__ __/--
- --- / /-- / /_/~>- __/ /__ ---
- --_<__/_-_<______/_ <_______/_--
- Turtle Group Incorporated
- http://tgi.home.ml.org/
-
- CFiX - Compare and Fix
- Copyright (c) 1996-97 John Pappas (DiskDude). All rights reserved.
-
- It is a crime to redistribute the contents of this package in a commercial
- venture of any kind without permission or a licensing agreement. Contact
- the Turtle Group Inc. via Internet email <tgi@iname.com> for more
- information on licensing.
-
- The included code is freely distributable for non-commercial use, however
- it is required that a) no modifications are made without written permission
- and b) you acknowledge the following copyright information:
-
- Copyright (c) 1996-97 DiskDude. All rights reserved.
-
- If you have any questions or comments, please contact the author via
- Internet email: diskdude@poboxes.com
-
- Contents:
-
- 1.0 Absract
- 2.0 How to use CFiX
- 3.0 Known bugs
- 4.0 CardWare information
-
- 1.0 Absract
- -----------
-
- Have you ever copied a file from a friend either over disk or modem and found
- that it was corrupt? You simply had to get a fresh copy, but when the file
- was 10-50 mbytes it took a while!
-
- CFiX will create a checksum of a corrupt datafile which is VERY small - approx
- 2 kbytes for a 16 mbyte file! You then give this checksum file to your friend
- and he/she does a compare on the original file. A new "fix" file will be
- created which contains only the data which needs to be replaced in your
- corrupt file to make it an exact copy of the original. In most cases, the fix,
- or patch, file will be less than 100 kbytes.
-
- It will then take only a minute to get the fix file and patch your corrupt
- file, saving you having to recopy/download the whole thing!
-
- 2.0 How to use CFiX
- -------------------
-
- Usage: CFiX [filename]
-
- Depending on what is in the file you specify by [filename], CFiX will do one
- of the following:
-
- o Create a checksum file, with an extension of ".sum"
- o Compare a file to the checksum file
- o Create a fix file with an extension of ".fix"
- o Patch a file based on a fix file
-
- The best way of illustrating how CFiX works is by going through a step-by-step
- example. Consider a file HAPPY.ZIP which we got from a friend and is a few
- MBytes in size. When testing the ZIP file, we get a CRC error.
-
- Firstly, we must make a checksum of the file, which basically makes a kind of
- "signature" of the file.
-
- C:\ZIP>cfix happy.zip
-
- You should have a new file called HAPPY.SUM in the same directory as the
- original file HAPPY.ZIP. The size of this file should be VERY small. Give this
- file to your friend whom you got the HAPPY.ZIP file in the first place.
-
- Using CFiX, your friend will compare this checksum file (HAPPY.SUM) to the
- original undamaged HAPPY.ZIP like so:
-
- D:\MYDIR>cfix happy.sum
-
- Note that the original file HAPPY.ZIP *must* be in the same directory as the
- file HAPPY.SUM. If a mismatch between the checksum file ("signature") and the
- original file HAPPY.ZIP is found, then a new FIX FILE will be created, with
- extension "FIX". In our case, HAPPY.FIX
-
- Get this FIX FILE from your friend. Again, this file should be very small,
- depending on how much of the file was damaged. Once you have this file, you
- can patch your corrupted file to make it the same as the undamaged original:
-
- C:\ZIP>cfix happy.fix
-
- Your original file HAPPY.ZIP should be fixed! Note that the original filename
- of the damaged file (when you typed "cfix happy.zip") is stored throughout the
- whole process so something doesn't stuff up.
-
- You may think that the method CFiX uses is confusing, however when I originally
- wrote CFiX, it seemed like the best way at the time... I still think it was a
- good way to process the damaged file - you only need to supply one argument to
- the program, and CFiX does its stuff intelligently.
-
- 3.0 Known bugs
- --------------
-
- o None
-
- Please report any bugs you may find to DiskDude <diskdude@poboxes.com>.
-
- 4.0 CardWare information
- ------------------------
-
- If you like and/or use CFiX, then you are required to send the author a
- PostCard of your beautiful city/town/country, along with a little description
- of the weather on the back and your email address if you have one.
-
- All PostCards which are received are digitally scanned and placed on the
- Internet for all to see. The URL is http://diskdude.home.ml.org/postcard.html
-
- Please send your PostCard to:
- John Pappas
- PO BOX 48
- Coburg 3058
- VIC, AUSTRALIA
- Thanks!
-
- [EOF]
-