***************************************************************************
              An effective use of DIET version 1.20
              ------  by Teddy Matsumoto ---------
***************************************************************************

1. Let's try DIET!
=================

   DIET.EXE is an executable file compressor as well as a file utility to
   compress DATA files. 
   DIET can compress executable files and can execute them from compressed
   as LZEXE or PKLITE. You can save a great deal of your storage space.
   What's REALLY NEW in this program is DIET compresses DATA files, too.
   
   Do we have to decompress the data file when we use them?
   Yes, you have to, when you use DIET as a non-TSR program.
   NO, when you let DIET stay as a TSR program.
   DIET automatically decompresses data files for you!
   DIET recompresses the files to the original if you wish!
   Let us try some examples first.

2. DIET is simple and is effective DIET.
========================================

   A rough classification of files of DOS may be in two categories,
   namely executables and data files. The executables activate Data
   files, in general.
   The number of files on your disk of the later category is greater
   in most of the cases than the former.
   DIET can compress both categories of files, but these two categories
   behave differently. Executable files are compressed with some self-
   extracting header and decompressed on the memory to the original
   format. Naturally there are executable files with overlays or
   files which overwrite itself. Data files on the other hand, have to
   be restored to the original form when they are referred from the
   executable files. The process is carried out manually or by batch
   mode ordinarily.

   The revolutionary idea of DIET is that the program takes care of
   expanding and compressing automatically while you are not conscious
   of what's really going on! If you are reading this file with DOS
   command MORE.COM, then stop it and try
     DIET MORE.COM  -------MORE.COM is compressed.
     DIET DIET120.DOC -----this document is compressed.
     DIET -Z     ----------let diet stay on memory. If you have EMM.SYS,
                           then you will see diet uses 1 page of EMS.
     MORE <DIET102.DOC --- to read the compressed file with compressed
                           COM file, a pager.
   How do you like it? Do not forget to type finally,
     DIET -ZR
   to let TSR part detached from your memory. If you're a man of curiosity,
   try MEM.exe twice, when DIET is on the memory and off the memory to know
   the size of TSR part of DIET.

   When DIET is stay resident on your memory, you can do your normal work
   as if none of your file is compressed by diet. There were many files
   with overlays which could not be compressed by LZEXE, PKLITE or by
   earlier version of DIET. The TSR mode DIET will handle these files
   easily without letting you be conscious of them being in compressed
   form.

   DIET in TSR mode has a very strong power and control over the programs.
   If you are anxious of any kind for the TSR mode, please start using
   DIET with non-TSR mode, till you could get a full understanding of
   its actions in TSR mode. DIET is worth using in non-TSR mode.

3.Use of DIET, non-TSR mode.
============================
   Type DIET to see all available options. 

   There are only 3 commands you have to remember in the non-TSR mode.
   -L,-R and -RA are the all you need to know now.
   Let us move to my directory c:\bin and type
     DIET -l
   to get the following list of files.

  TAIL.EXE       UUDECODE.EXE   UUENCODE.EXE   EMACS.EXE      EMACS.HLP    
  BDIFF.EXE      BDIFF.DOC      BUPDATE.EXE    CSH.COM        LHA.EXE      
  LOG.EXE        SETUPE.EXE     CFREQ.EXE      REV.EXE        SORT.MAN     
 
  After I typed
   DIET *.*           ---------compress all the files!
   DIET -R *.*        ---------restore non-executable files!
  The same command line I type to see what happened.
     DIET -L          --------- list dieted and undieted files!
  In the following list, filenames headed with an asterisk *, show
  their names in reverse color.

 *TAIL.EXE      *UUDECODE.EXE  *UUENCODE.EXE  *EMACS.EXE     EMACS.HLP    
 *BDIFF.EXE      BDIFF.DOC     *BUPDATE.EXE   *CSH.COM       LHA.EXE      
 *LOG.EXE        SETUPE.EXE     CFREQ.EXE      REV.EXE       SORT.MAN     
 
  DATA files in the above list are BDIFF.DOC EMACS.HLP and SORT.MAN.
  The amount of space saved by compressing data files were:

   Compress 'BDIFF.DOC' ....Success! (15799 to 6659 bytes)
   Compress 'SORT.MAN' ..   Success! (6139 to 2487 bytes)
   Compress 'EMACS.HLP' ... Success! (8561 to 3663 bytes.

  You should know the amount of space you could save if you can
  compress all of data files, 'doc','man' or 'hlp' extensions.
  However, DATA files must be in uncompressed form when they are called
  from PROGRAM. Consequently you have to save DATA files in the original
  size when you are in non-TSR mode. Remember compress every thing and
  restore DATA files, or compress only executables with '.EXE' and '.COM'  
  extensions.

  The command -RA restores all the DIETed files including executables.
  There were many questions about how to backup programs, or where is
  -b switch of DIET. DIET never failed to restore original programs
  except when your computer is off in the process of compressing or
  recompressing. In such cases please look for files with __DIET__.???
  temporary files. Your programs may be found among them.


  4.DIET in TSR mode.
  ===================
  To compress DATA files after using them, you type 
     DIET -Z -P
  to get the information
      
   |Stayed on memory! (use EMS 1 page)
   |  auto recompress : on (with messages)
   |  temp. directory : D:\
   
  You may disable the action of DIET by
   
     DIET -ZD,
   
  and activate it again with
   
     DIET -ZA.

   |TSR function is activated!
   |  auto recompress : on (with messages)
   |  temp. directory : D:\
   
  DIET has a new feature from this version on to compress device drivers.
  Suppose you have lines in your config.sys:

    |DEVICE=C:\DOS\SETVER.EXE
    |DEVICE=C:\DOS\HIMEM.SYS
    |DOS=HIGH
  You may compress your device driver by -D switch.
      DIET highmem.sys

    |Compress 'HIMEM.SYS' (as device driver) ...
    |Success! (11552 to 7043 bytes)
   
  and still you can boot your system. This new ability of DIET was designed
  primarily for large device drivers of Japanese language Front-End Process-
  ors.

  EDIT.COM is not compressed because it is too small.
  You may now try the auto-recompress feature of DIET.
  Compress packing.lst with DIET and edit it with EDIT.COM.
  Say add a single line. Then save the file and exit. You see a message,

    |Compress 'C:\DOS\PACKING.LST',
    |Success! (2608 to 1278 bytes).

  The situation is different when you use other editors. You will get a 
  backup file 'packing.bak' and new 'packing.lst' where backup file
  remains in the compressed file and the newly edited file is expanded.
  
  There are two kinds of DATA files opened with mode read-open and with
  read-write mode. DIET generate a temporary file for the read-open file
  and erase it when program terminates. For read-write files, DIET tries
  to recompress the edited file. Some editors copy the original and works
  with buffers, and erase the original when program terminates. You must
  find out whether your editor will recompress with TSR DIET or not.
  EDIT.COM of MSDOS ver. 5.00 recompress under DIET. EDLIN.EXE will not
  work for editing compressed file.

  In earlier version of DIET, ver.1.0x, we did not supply automated
  compression. From ver.1.00, you may activate this function with
  -P command. Resident part of DIET will try to compress the edited
  file when Program terminates and frees its memory area. 
  
3.Basic Functions of DIET.
==========================
    There are 5 basic functions of DIET.exe,i.e.
    To COMPRESS files:  -I,-D,-V,-B -P options;
    To DECOMPRESS compressed files: -R -RA options;
    To make DIET terminate and stay resident: -Z,-ZA,-ZD, -ZR options; and
    To list files or to test for compressed: -L -H -! options.
    To copy files with compressed or decompressing: -c option.

  Usage:  DIET [options] [file_names].
  Options: -L,-R,-RA,-Z,-ZA,-ZD,-P,-M,-B,-V, -D, -C, -O, -T, -I, -J, -H,
           -A, -! and -K.
          You may use '-' of '/' as the switch-character as you prefer.
          To specify multiple of tion, please insert a space between them,
          like
              DIET -Z -P -M.
          If you do not specify option, then the function is to compress.
          Or if you don't specify any option nor file name, then diet
          will display the help screen.
          You may specify options -B, -V, -I, -J, and -A under the
          environmental string DIETOPT. By typeing in these options
          later on your command line, you may toggle their functions.

   File_Names: You can't omit file name input except for -L option.
          You can use wild cards and multiple filenames on the command
          line.

  Usage 1.
  ========
   File Compression: 
          If none of the options -L,-R,-RA,-Z,-ZA,-ZD,-C,-H or -!
          is specified, Diet compresses specified file(s).
 
    COM/EXE files.
    Files with extensions '.EXE' or '.COM' will be compressed with
    a small header file added. The header will let the program extract
    itself and let it execute. When -V option is specified, header will
    not be attached. See the Overlay mode.

    Executable files without COM/EXE extension.
    There are files with extension not '.COM' nor '.EXE' but seems
    to be executable files. DIET will skip compressing them without
    -V or -I option. But with these options, DIET compresses them as
    executables.

    Device Drivers.
    When a file starts with FF FF block, DIET will skip compressing.
    These files can be compressed with -D option. If you use -D -I
    options together, files starting not with FF FF can be compressed
    as device drivers

    Any other files.
    DIET compresses files not described above as DATA files. DIET can
    access these files when DIET stays resident on memory.
   
          Different headers will be attached to compressed files
          according to the extensions COM, EXE or SYS respectively.

    DIET will skip any files already compressed by DIET. DIET skips
    files with extension '.LZH'. DIET will skip small files less
    than a cluster unless you specify -B option.

    IMPORTANT NOTE. DIET will overwrite on the original files except
          with -O or -C option. To save storage space DIET makes no backups
          in principle. If you are not sure of the result, please take a
          backup of the file(s). You will be assured of safety using DIET for
          certain period, however.
          Specifically, when you use other TSR programs, we strongly 
          recommend to take backup of files.

          The dynamic Lempel-Ziv method adopted in the software may fail
          to compress files compressed by other tools. The success or
          failure in compression is determined by the number of clusters
          a file needs for storage. If you use -B option, then success
          depends on byte-count.

   Usage 2. File Decompression.
   ============================
          With -R or -RA option, DIET decompresses files
          it had compressed. With '-R' option files with extensions
          EXE/COM/SYS remain compressed and other files are restored.
          Namely, this is to restore all the data files to the original.
          With '-RA' option, you could restore all.

   Usage 3. TSR On/Off.
   ====================
          Option. '-Z' to load -ZR to remove from memory.
          DIET -Z or -ZR
          will announce either "stayed on memory' or "removed from memory".
          When you compressed COMMAND.COM or when you compressed some
          overlay files, you need DIET to be resident on, memory.
          I recommend you to write a line "DIET -Z" in your autoexec.bat
          file, when you use DIET frequently.

          DIET uses 1 page from EMS (Lotus-Microsoft) if it finds one. 
          The size of the resident part is reduced by the EMM.sys utility.
          After you type;
            DIET -Z -P
          you get the announce:
            |Stayed on memory! (use EMS 1 page)
            |   auto recompress : on (with messages)
            |   temp. directory : D:\
    
    DIET -ZR  ---------------- remove resident part of DIET from memory.

    IMPORTANT NOTE. This is not only for DIET.
          If you use multiple TSR programs, be careful to unload
          following the reverse order they were loaded.

    Temporarily Enable/Disable TSR part of DIET.
          DIET -ZD  disables resident part of DIET without unloading.
          DIET -ZA  enables resident part of DIET without reloading.
          The second command restores the resident DIET when an
          interrupt was received from keyboard or from any other device's.
          Remember this switch, when you pressed Ctrl-C or Ctrl-Break
          while DIET had been acting.

    Automated re-Compress Facilities.
         DIET -P-------------enable automated recompress.
         DIET -P -M ---------enable automated recompress without message.
         DIET -TD:\ ---------temporary files generated on D:\.
                             You may specify the same by
                             "set TMP=D:\"
                             in your autoexec.bat.
         Files retrieved by the DIET's resident part,
         files opened by Write-Open or RW-open modes and
         files overwritten on the old file by file-creation
         can be re-compressed. You may need to know by making tests.

         This function is activated when dos-call INT4C is called.
         This is when the program terminates. I don't want to interrupt
         any program for the compression, nor I don't want to make the
         resident part of DIET larger than the present. These are the
         reasons for the limited facility of the present design.

    Usage 4 -L-H,-! Options.
    =======================
    [LIST files compressed with DIET,-L option.]
         DIET -L
         will list files compressed with DIET. You may skip wild card
         for the option.

    [Check Files Compressed by DIET,-H option.]
         DIET -H <file_name >.
         Check the file if it is compressed by diet, and checks CRC
         for the integrity. Displays:
         |Compressed File Size with CRC.
         |Original File Size and Type.
         |If -K option is specified, report K option.

    [File Validation, -! option.] 
         DIET -! -----------displays its own validation.
         DIET.EXE is original file!

    Usage 5. Copy, -C option.
    ==========================
      Copy DIETED files may cause extra time. Since COMMAND.COM will
      decompress the file first and copy to the directory and TSR DIET
      will recompress the file again. You can use -C option to copy files
      as compressed as they are. If DIET finds newer file(s) with same name(s), 
      then DIET will skip the files(s).

   (1)   DIET -C<destination> <filenames> 

      When you store compressed files of Floppy disks, and use them
      on a RAMDISK, you may use this method to restore files compressed.

      <Example 1.> To copy all the files on the current directory c:\
       to Floppy Disk A:
         DIET -CA:\ C:\*.*  
        ~~~~~~~~~~~~~~~~~~~
   (2)   DIET -RA -C<destination> <filenames>.
    
      When you keep files compressed on floppies and use them on a RAMDISK
      in decompressed shape. You may copy file(s) with restoring to the
      original size(s).

      <Example 2.> To copy compressed files on Floppy disk in drive A:,
      to a RAMDRIVE C:\ in the original size for faster execution.

         DIET -RA -CC:\ A:\*.*
         ~~~~~~~~~~~~~~~~~~~~~~~

    
    [Backup Files, Output Directories, -O option.]
         By default, DIET overwrites files by compressed equivalent with
         the same name. So if you want to back up the files before you
         apply DIET with -O option.

      <Example 1>. You are not on DRIVE A: and you want the compressed file
         of alpha.dat on A: with the same name on your current directory:
             DIET -O A:alpha.dat.
  
      <Example 2>. Compress the file alpha.dat on the current directory
         compressed, and record it on the directory C:\TEMP:
             DIET -OC:\temp\ alpha.dat
                 ^          ^    
         Please note the positions of the spaces and back slashes.

      <Example 3>. beta.dat has been compressed by DIET on the current
         directory. Decompress this file and record it on the root directory
         with the name alpha.dat:
             DIET -R -O\alpha.dat beta.dat

    [Specify Directory for temporary files, -T option.]
    
         By default, DIET makes temporary files on the current directory.
         It is recommended to specify the directory on which temporary
         files to be made with the TSR mode. DIET makes temporary files
         very frequently in TSR mode, consequently, if DIET could use
         High Speed Memory Devices, DIET runs smooth and easy.
         In case of nonresident mode, DIET compress and decompress on
         memory, in principle, so you need not use this option.
             DIET -Z -TD:\temp\  , where d: is supposed to be a RAMDISK.
         DO NOT FORGET THE LAST "\" in this option.
                                ~~~
    [Bytes Counts -B option.]
         DIET says success in file compression if a cluster in the
         storage supposes is saved. If you specify this option, you
         can get Bytes Comparison for the success or fail of compression.
         Since DIET overwrites files within clusters, this option is useful
         when you are to store files in an archive like LHA with no compress
         option.         

    [Overlay mode -V option.]
         DIET compresses executable files with headers for self-extraction.
         However you may compress an executable file without this header
         by decompressing it as a temporary file and let resident DIET to
         activate its execution if you have DIET resident in your memory. 
         You can execute a huge file in overlay mode by this option, say 
         a file of size more than 400KB. This mode has a side-effect in
         the size of compressed executables hence the header is missing.

    [Device Drivers compression -D option.]
         From this version on, you can compress device drivers, too.
         Device driver is a file with '.SYS' extensions usually, and
         is used with a line 'device=?????.sys' in your config.sys
         file. DIET checks whether a file is a device driver by the 
         leading FF FF block of the file. There are some device driver
         without this block. You have to use -I option together with 
         -D option.

    [Ignore warning -I option.]
         DIET ordinarily stops compression for the files with overlays
         when the size of the file in EXEHDR information is not the
         same, with the message 'may be overlay files'. Since DIET can
         take care of overlay files in the TSR mode, DIET may ignore
         warnings and continue compression with '-I' option.
         
         Those who use DIET only in nonresident mode should refrain
         from using this option. There are EXE files which are loaded
         in high memory. DIET warns you with the same message as
         overlays, but you can't expect to have a smooth action with
         such executables.

    [Enable Automated re-compress option -P.]
         Automated recompression is off by default. In order to get
         your file compressed automatically to the compressed size,
         you have to set this option.

    [No message option -M.]
         If your screen is mixed up with the messages from
         DIET activated as a child process from your editor etc.,
         use this switch to make DIET silent.

    [Japanese Messages Outputs: DIET -J]
         I am sorry that some witty succinct Japanese messages are
         not imbedded in English messages. However, if you have
         JDOS4.0 from IBM Japan, you may listen to the advice of
         DR.Matsumoto on the present shape of your disk health status.
  
    [Read Only Attribute option, -A.]
         This is only for the sake of safety. This will make all
         the data files to have attribute read-only. If you are using
         DIET in resident mode, your editors invoke diet to decompress
         a compressed file, if not your data files are not compressed.
         In case your editor opened a compressed file, when you don't
         have DIET resident, your editor may not be able to quit from 
         editing compressed binary file. A rare possibility, it might be.
         This switch makes all the compressed file to be read-only.
         You can not edit a file without changing its attribute.
         Please note, if you copy a file from the original position,
         then its file size will normally be restored to its original
         size.

    [Kill temporary Files when you quit -K option]
         Resident part of DIET opens a temporary file whenever a
         compressed file is opened in read-mode. The temporary file
         is erased whenever the program closes the file. However,
         there are programs which open and close a file frequently,
         e.g. a Help Message file, creating and erasing temporarily.
         This type of file is very much time consuming for TSR DIET.
         
         The option -K should be used when you compress a file with
         DIET. This is a new option, from this version DIET ver.1.20.
         You must remember you need a fairy large amount of space for
         your temporary file. The temporary file will be erased when
         the program terminates.

         You can check whether your file is compressed with -K option
         or not with -H option.

4. Environmental Variables.
===========================
      DIET from version 1.02x refers to the following environmental strings.

      DIETOFF  File_names for which DIET is disabled to act in resident
               mode.

      DIETSIZE File_names which returns the real size of compressed
               files when referenced.

      TMP      Specify directory to generate temporary files.

   ** NOTE reference to environmental string is possible only in MS-DOS 
      ver3.xx or after.

 [DIETOFF] DIET in its resident mode has a powerful control over
      files. In return, we have to be careful for its adversary actions.
      For an example, when you copy compressed files:
         COPY HIMEM.SYS
      you will know HIMEM.SYS has the original uncompressed file size.
      Of course you can type:
          DIET -ZD
          COPY HIMEM.SYS
      to produce an exact copy of compressed size, yet it is better to
          SET DIETOFF=COMMAND.COM;FC.COM;DUMP.EXE;XCOPY.EXE
      to the effect typing, dumping and copying without re-
      producing files to original sizes.
      
      Register names of program to DIETOFF to disable reproduction
      of the uncompressed files. You don't have to specify full path
      names. DIET just ignores them and is concerned with program
      names only.

  [DIETSIZE] There are programs which read in data files only to the
     size obtained by the Function Call AH=4Eh/4F/h. In earlier versions
     of DIET, it fails to read the data properly for such programs.
     This string refers to such programs.
         SET DIETSIZE=**.COM;***.EXE
     will enable **.COM and ***.EXE to read compressed MSG or HLP
     files, and will disable them to return "Wrong file" messages.
     Unfortunately, there are many files including SK.COM, which
     checks data files with other methods for different versions.

  [TMP]  You may set this environmental string in your autoexec.bat
     file as  'set TMP=d:\'. Command line -T option like 'DIET -TD:\TEMP'
     overrides the setting.

5. Concluding Remarks.
======================
  [You can't use DIET for Norton's SD]
     The resident part of DIET can take file handlers swapped from
     the compressed original. If a program does not use a file-handle
     and works directly on FAT table or FCB, then it is not activated        by resident DIET. Please type DIET -ZD when you use programs
     with names like HDD Optimizer, Speed Disk, DOG or Harddisk manager.

  [File Open Error message.]
     When DIET is resident in your memory, you may see a message
     "Can't find abc.exe" even if the file exists. This is often
     with the case when DIET cannot find enough space on your
     temporary directory. Because some programs say "can't find"
     when it fails to create a file. Please check your space if
     you see this message.
     From version 1.10 on, DIET will beeps at you when DIET fails
     to decompress a file.

  [Executable Files with extension not COM/EXE.]
     There are some executable files without the extensions EXE/COM.
     DIET tries to differentiate such files from DATA files.
     If you specify either -I or -V option to compress these files
     as overlays or self-executables. Executable files are to have
     EB, E9, E8, 0E, 1E, 06, BC, FA, FB, FC, or FD as leading bytes.
     Naturally, there are DATA files with one of these as the
     starting bytes.

  [Temporary File Names.]
     Using DIET in resident mode, you will often see files with
     names such as __DIET__.*. You will get these files when you
     reset system or stop execution by Ctrl-Break. These are the
     temporary files generated by DIET. You may or may not erase
     those files, since they are under constant transactions.

  Acknowledgements.
  =================
  To all users, the version has been well tested by many 'brave' people
  who were not afraid of uncountable backups, collisions with other 
  TSR's or RESETings. However, I am sure, yet, of unexpected
  bad timings with other resident programs or devices. Please be
  warned against the use of this software with other resident programs
  especially in its resident mode. The author can not be liable for
  the damages caused by the use of this program. Backup your files
  before testing every time you use with a new program.

  To Haruyasu Yoshizaki who found the vital bug which I could not find
  up to the last moment,
  to K.Okubo who introduced this software outside Japan,
  and to my friends in Fgal/Flabo forums on Nifty Serve who
  dared to hang on the earlier versions in spite of the hang overs
  from so many Hang Up's.

  Our Distribution Policy.
  ========================
  The program together with the other packaged documents is copyrighted 
  by Teddy Matsumoto. Package consists of DIET.exe, DIET120.DOC,& update.doc.
  You may copy, distribute and use this program free of charge
  under the conditions.
   You must not charge for copying or distributions,
   you use this for your personal purposes,
   you are to follow up versions if you distribute, and
   you must copy or distribute the entire package.

  How to contact the Author.
  ==========================
  Email to Teddy Matsumoto at GBG00230 on Nifty Serve.
  Overseas Users may contact K.Okubo at one of the following:
                             74100,2565  Compuserve, 
                             K.Okubo Genie, 
                             okubok@tansei.cc.u-tokyo.ac.jp

===== REVISION HISTORY =====

 Version 1.00x    Beta Test version.

 Version 1.01a (02/01/91) The first TSR version.

 Version 1.01b (02/16/91) New routine added to detect the use of EMS.
                          Some improvement for software hooked on
                          disk I/O routine by function call int21h.
 Version 1.02a (02/27/91) Use of EMS to minimize the resident part.
                          Environment Variable DIETOFF is introduced.
                          Any program registered in DIETOFF will disable
                          DIET. Namely, copy, an interior command of
                          COMMAND.COM, if registered as DIETOFF, will
                          disable DIET while copying files. That is,
                          you can copy files as compressed as they are.
                          EX. set DIETOFF=COMMAND.COM;DIET.EXE;DUMP.EXE
                          
                          Another Environment Variable DIETSIZE now
                          takes care of the files which load only a
                          portion of the program as is indicated by
                          size obtained from intAH 4Eh/4Fh.

                          New routine is supplied to distinguish character
                          devices.
 Version 1.02b (03/04/91) Environmental String "COMSPEC" had to be at
                          the top of Environment Area, when COMMAND.COM
                          is specified to DIETOFF.
                          A bug fixed for the resident mode in which
                          temporary file was not correctly generated to
                          the directory specified by -T option.
               
 Version 1.10a (4/1/91)   Automated compression supported. -P option.
                          -Z option does not toggle -ZR option added.
                          -B option -V option added.
                          New environmental strings DIETOPT and TMP.
                          BEEP when DIET fails to create file.
                          Function call AH=4B03 is taken into account.
                          Can compress files with size more than 1MB.
                          A bug fixed for -O option.
 Version 1.10 (5/12/91)   Warn against the coexitent DIET versions.
                          Temporary file remaining when the file is
                          opened with file sharing mode. This bug is
                          fixed. Check against executables without
                          COM/EXE extension. DIET auto-checks -! option.
                          (8/20/91)
  ==================End of Diet120.doc=============================