Readme file for TwinTracker 2.1 for MS-DOS, Windows 3.x/95 + NT - Aug 03, 1998

TwinTracker is a MS-DOS utility program which can detect duplicate files,
files of exactly the same size (in bytes - still duplicates in high probability)
and files of the same name in a specified directory on your harddisk including
all subdirectories.

I. Terms and conditions:

TwinTracker is released 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.  Please refer to the GNU General 
Public License for more details. In case you haven' t received a copy of the
GNU General Public License along with the program, please write to the
Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

DEPARTING from the rules of the GNU General Public License please notice
the Following: TwinTracker is free software but it is NOT public domain. This 
means you can use it free of charge, redistribute but NOT modify it without
the permission of the author. If you decide to redistribute it you are obliged
to add this file to the program.

II. Requirements:

The program will (as tested so far) run with original MS-DOS (6.x), Windows 3.x,
Windows 95 and NT. As it is based on DOS commands there has to be a DOS
command interpreter (like command.com) installed on your system. In a file system
with access limitations TwinTracker may not run properly. It may also not run stable
on some Windows NT platforms.

III. Functions:

The program is almost self-explanatory. However, you should take a minute to read the
following descriptions as they might answer remained questions or help you to solve a
problem:

A. The option keys:

By Default TwinTracker will scan the directory you choose (hit <Enter> after you typed
in the name) including all subdirectories, compare all files among each other exactly 
(Scan Mode 1) and report the duplicates while pointing out zero-length files. 

- If you want TwinTracker to compare the files by Size only (Scan Mode 2 - faster but 
  less reliable) or to compare them by their Names only (Scan Mode 3) change this
  setting  by pressing <F1>.

- If you don' t want Subdirectories to be included change this setting by pressing <F2>.

- If you don' t want Zero-Length Files to be reported change this setting by pressing <F3>.

- If you want the single comparisons between files not to be done by the TwinTracker
  Engine but by the DOS program/utility FC (files compare) change this setting by pressing
  <F4>. 
   |WARNING: This option is still experimental! The idea of it is to let TwinTracker only look
   for files possibly duplicates but to give FC the task of comparison in detail. I found out that
   this can only be faster if FC performes an ASCII comparison which is, of course, not correct
   for binaries, but as I found out about 99% of all binaries can be filtered out or identified as
   duplicates that way, too. If you suddenly see a blank command line during the process of
   comparison you know there was a binary belonging to the 1% causing FC to crash. But this
   does not necessarily mean TwinTracker crashed, too!
   Type in "Exit" and then immediately hit <F5>. After this you will be able to quit the program
   properly. You could even proceed but the user interface won' t look that nice any more.
   
   The error message "Access failed!"   "File1" <> "File2" is typical for the option "Use MS-DOS
   FC". Please do not report it to me if it occurs under this setting - just do without it. 
   Above all, please keep in mind that the results are less reliable if FC was used.

   For version 2.1 I defined certain conditions on which the TwinTracker engine will be used even
   if you have choosed the option "Use MS-DOS FC". The reason for it was to achieve more sta-
   bility. Always if you see the "Tracking down!" appear in the Scan-Window the TwinTracker
   Engine is in use.


B. Miscelaneous tips, tricks and hints:

For Win95 users it is important to know that TwinTracker may (surprisingly) run quite
slow if you decide to start it in MS-DOS Mode. Especially the process of reading  files
from the directory you search through can be slowed down dramatically. Even if you' re
able to abort in any time by pressing <F5> it is strongly recommended to run the program
directly from the Win95 environment without choosing MS-DOS Mode. Improvements on
the performance in MS-DOS Mode were made from version 1.2 to 2.0 but there' s still a
measurable difference and in any case you won' t gain speed with it.

In case you intend to scan Word Documents be aware of a curiosity I noticed in
Word 97. If you save a document - let' s say as "1.doc" - then save it again unchanged
as "2.doc" the two files 1.doc and 2.doc will be exactly of the same size but they possib-
ly won' t be identical. Don' t believe me? Maybe ask Microsoft which sense it makes. 
However, you will have to use Scan-mode 2 (compare files by size only) to filter out 
these "duplicates".                           

In Win95, you can add a shortcut to the start menu by opening Windows Explorer,
clicking on ttracker.exe, selecting Create Shortcut under the File menu, and moving
the shortcut into the Windows/Start Menu/Programs folder, or a subfolder of it.
An icon file for use with the program is added as well.

C. Secrets:

- Just hit <Enter> instead of typing in a directory if you want the current directory to be
  searched.

- Hit the <Tab> key instead of <Enter> for a Non-Stop-Scan! TwinTracker will display the
  duplicate files found on the screen and save them to "Duplicat.tmp" in the searched
  directory but not stop each time a pair of duplicates is found and ask you to hit a key 
  to continue (useful if there' s a large number of duplicates to be detected).

- To scan a subdirectory of the current directory you can type in its name without the 
   complete path (example: if current directory is "c:\" and you want to scan "C:\temp"
   you can type in "temp" instead of "C:\temp").

- TwinTracker has a graphical user interface but you can use it with the following
   Syntax from DOS prompt as well:

   ttracker.exe [path of directory to search through] 

   Options are not available this way (maybe in any future version).

D. Limitations:

TwinTracker was not developed to search for duplicates on Floppy and CD-ROM drives.
I did not add this feature because I think it's almost useless: From a CD-ROM you can' t
remove any data and the content of a floppy disk can easily be copied to the harddisk
where access is a lot faster.


IV. Known problems in DOS/Win 3.x:

There' s one very special problem known with DOS/Win 3.x:
Usually directory names in DOS/Win 3.x can not contain Spaces (if you try to create such
a directory using "mkdir" you won' t succeed). However, I had such a directory created by
a chess program on my own system. As TwinTracker is intendet to run in Win95/NT, too,
where these directory names are valid, it can not simply skip them. Unfortunately I didn' t find a 
way to access on a DOS/Win 3.x system through DOS yet. So TwinTracker will complain with
a flood of error messages. If you have an idea how to access such a directory (through DOS)
please let me know.


V. About the results and how to handle them:

TwinTracker will NOT delete any files on your system except temporary files
created by the program itself (in a temporary directory which will be completely
removed when exiting the program). All duplicate files found will be saved to a file
named "duplicat.tmp" in the searched directory. If you have a DOS Editor which
can be run by typing in "edit [filename]" at DOS prompt you will be able to edit 
"duplicat.tmp" directly from within the program after the search process is 
finished. Press Spacebar then to do this.
|You should verify all the results yourself before deleting anything! Please
be careful, especially if you want to remove files from critical folders like 
"C:\Windows", "C:\Windows\System" or "C:\Dos". 

VI. Files:

The archive ttrack21.zip you received should contain the following files:

    TTRACKER.EXE        Executable file (packed with DIET) - the program
    TTRACKER.ICO         TwinTracker icon file
    README.TXT            This file
    GNU.TXT                     GNU General Public License


VII. History:

Version 1.0 - not made public and in German language

Version 1.1 - the original release in German, TwinTracker finds duplicate files
                       in single directories, the only option to choose is exact comparison
                       and comparison by size only, access violations could happen when
                       TwinTracker tried to access files in use by the OS or another process
                       (fixed since version 2.0)  

Version 1.2 - similar to the 1.1 version with slight improvements but in English 
                       for the first time, published over Simtel.Net

Version 1.3 - intended to follow the 1.2 version but skipped because of major changes
                       to the program

Version 2.0 - new options added: 
                       "scan subdirectories" (Y/N)
                       "report zero-length files" (Y/N)
                       "use MS-DOS FC" (Y/N)
                     - 100% more speed by improved sorting of the files 
                     - access bug fixed as described above
                     > major problem was (and still is) the difference between the file system in
                        original DOS and Windows 95/NT

Version 2.1 - new options added:
                       "compare files by names only" (a little bit slow yet)
                       edit "duplicat.tmp" from within the program
                     - about 20% more speed compared to TwinTracker 2.0
                     - several minor bugs fixed

Please report bugs and suggestions to:

    Stephan.Meyer@t-online.de

Advanced versions of TwinTracker will probably be available at URL:

    http://www.geocities.com/SiliconValley/Hills/1698/index.html

Thanks for using this program!

Stephan Meyer