PAK

                          File Archive Utility for OS9
                                  Version 02.02


                       (c) Copyright 1987 by G.B. Janssen
                              ALL RIGHTS RESERVED









































                                Table of Contents



     Introduction  ....................................................   1
     Using PAK  .......................................................   3
     PAK commands  ....................................................   4
         Adding files  ................................................   4
         Moving files  ................................................   4
         Updating files  ..............................................   4
         Extracting files  ............................................   5
         Removing files  ..............................................   5
         Printing files  ..............................................   5
         Testing an PAK  ..............................................   5
         Directory Listing  ...........................................   6
         Backup retention  ............................................   7
         Suppress compression .........................................   7

















































                                  INTRODUCTION


     PAK is the copyrighted property of G.B. Janssen and is not public domain
     software.  You may distribute it, upload it, download it, use it, etc, 
     etc, as long as it is FREE. It may NOT be used as part of any commerical
     ventures, nor as a sales aid without the expressed written consent of
     th author.




















































     PAK                                                           Page 0001






     PAK is used to create and maintain files in groups. Such groups are
     usually called an archive (in this document it is called a PAK). PAK 
     automatically compresses the files being archived, so that the 
     resulting PAK takes up a minimum amount of space.

     When PAK is used to add a file to an PAK it analyzes the file to
     determine which of four storage methods will result in the greatest
     savings.  These four methods are:

     1) Huffman squeezing; the file is compressed into variable length bit
        strings, similar to the method used by SQ programs found on IBM
        PC's.

     2) No compression; the file is stored as is.
        NOTE.. That since this methods involves no compression at all, the 
        PAK entry will be larger than the original file do to overhead.

     3) Run-length character compression; repeated sequences of the same byte
        value are collapsed into a three-byte code sequence.

     4) Lempel-Zev compression;  the file is stored as variable size bit codes
        which represents character strings.

      PAK was developed on a Tandy COCO3 OS9 Level II system using Tandy's
      "C" compiler.  ***** Will run on Level I and II. *****

      Some notes:

      1.   Bugs.mge was downloaded from Delphi COCO graphics database.
           This is a COMPRESSED graphics picture of Bugs Bunny that is 
           input to COLORMAX (input size=21248). Using it as a test for
           PAK a saving of 50% in disk storage space was obtained (output
           size=10575).

      2.   A 1,000,206 byte text file (many "C" and ASM sources merged)
           resulted in a 532318 byte output file, a saving of 467888
           bytes (46%).

      3.   Using PAK to distribute text, source, binary, graphics, fonts,
           etc. eliminates the need for multiple transmissions. It also
           solves the long discussed problem of needing special protocols
           and programs to eliminate characters added by XMODEM. PAK 
           ignores any chararcter added to the end-of-the-file.

       4.  Due to work/backup copies, the largest PAK can only be approx.
           1/2 the capacity of media being used.  If using a 40 track DSDD
           disk drive (40trk * 18 sec/trk * 256 byte/sec * 2 no. of sides
           = 368640 bytes) (360KB) then the maximum PAK would be about
           179KB or 183296 bytes.

       5.  PAK uses OS9 command "rename". It must be available in the
           current execution directory or loaded in memory prior to
           executing the PAK command. When using PAK with large files
           or files on multiple diskettes, preload both programs 
           ("load pak rename"), change diskettes then issue PAK command.

       6.  MAXIMUM input file size is 1,048,575 or $FFFFF.


     PAK                                                           Page 0002





                                    USING PAK



     If PAK is invoked with no arguments then a brief command summary is 
     displayed.


                           OS9 Pak Version 02.02
                           (c) 1987 G.B. Janssen
===============================================================================

 Usage: pak -{amuexrpdltb} archive [filelist]

 where: a = Add files to a PAK.
        m = Move files to a PAK.
        u = Update files in a PAK.
      e,x = EXtract from a PAK.
        r = Remove files from a PAK.
        p = Print files from a PAK to stdout.
      d,l = Directory (List) of files in a PAK.
        t = Test integrity of files in a PAK.

     alter how a command works:

         b   = retain Backup copy of PAK.
         s   = Suppress all compression.

     NOTE The "B" option may be added to Add, Move, Update, Extract 
     or Remove.  The "S" option may be added to Add, Move or Update.

     Archive is the name of the PAK to use or build.

     Filelist is a list of up to 40 file names to Add, Move, Update,
     Extract or Remove.

     Commands may be in UPPER or lower case.























     PAK                                                           Page 0003





                                  PAK COMMANDS



     This section describes each of the commands.  PAK will only accept 
     one command at a time. 


     ADDING FILES

     NOTE.. Files added to the PAK retain date-last-modified for use in    
     Update command.      ...NOT DATE ADDED TO PAK...

     Files are added to an PAK using the "A" (Add), "M" (Move), or "U"
     (Update) commands.  Add always adds the file.  Move deletes the source 
     file once it has been added to the PAK.

     Update adds the file to the PAK if not present.  If present, date last 
     modified is use to determine older of the two, which is kept in the
     PAK.

     To add the file named "JUNK.DOC" to an PAK named "TEST.PAK", you 
     would use the command:

         pak a test junk.doc

     To move the file named "JUNK.DOC" to an PAK named "TEST.PAK", you 
     would use the command:

         pak m test junk.doc

     To update the file named "JUNK.DOC" in an PAK named "TEST.PAK", you
     would use the command:

         pak u test junk.doc

     You may also add, move or update a file which is in a directory 
     other than your current directory.  

         pak a test /d1/mystuff/junk.doc 

     The above commands add, move and update will accept more then one
     filename from the command line.

         pak a test junk.asm junk.doc /d0/cmds/junk

     PAK does not save the path name.  In other words, if you specify a
     path when adding a file, only the actual file name is stored in the
     PAK.  In the above example junk.asm, junk.doc and junk are the
     file names stored.

     Duplicate names may not be added to a PAK. The following example
     will result in an error.

     pak a test junk /d0/cmds/junk





     PAK                                                           Page 0004





     EXTRACTING FILES

     PAK entries are extracted with the "E" (Extract) and "X" (eXtract)
     commands.  For example, if you had an PAK named "TEST.PAK", and
     you wanted the file in it named "JUNK".

         pak e test junk      OR    pak x test junk

     If you wanted to extract all of the files in an PAK named
     "TEST.PAK".

         pak x test           OR    pak e test

     Whatever method of file compression was used in storing the files is
     reversed, and uncompressed copies are created in the CURRENT
     DIRECTORY (not in directory they were originally from).


     REMOVING FILES

     PAK entries are removed with the "R" (Remove) command.  For
     example, if you had an PAK named "TEST.PAK", and you wished to
     delete an entry in it with a filename "JUNK".

         pak r test junk


     PRINTING A FILE

     PAK entries may printed with the "P" (Print) command.  This works
     the same as extract except the file is written to stdout, which in
     turn may be redirected '>' or piped '|' as required.

         pak p test junk   OR   pak p test junk >/p  OR   pak p test | sort

     NOTE... Files are printed regardless of type (text, binary or graphics).
     So be careful.  Also no headings/total are printed to stderr.

     TESTING AN PAK

     The integrity of an PAK may be tested by use of the "T" (Test)
     command.  This checks to make sure that all of the entries within  
     a PAK are in good shape.

     This can be very helpful for critical PAKs, where data integrity
     must be assured.  All of the entries in the PAK are unpaked
     (without saving them) and the CRC value is recalculated and
     compared with the CRC value saved at the time the file was stored.

     Example, if you just downloaded an PAK named "TEST.PAK" from your
     favorite bulletin board, and you want to make sure that you received 
     it properly, enter the command:

         pak t test






     PAK                                                           Page 0005






     LISTING PAK ENTRIES (Directory)

     You can obtain a list of the contents of an PAK by using the "D"
     (DIR) command or the "L" (LIST) command.  To see what is in an 
     PAK named "TEST.PAK".

         pak l test           OR     pak d test


                           OS9 Pak Version 02.02
                           (c) 1987 G.B. Janssen
===============================================================================
Name                   date   time    --orig length- --out length--  action 
===============================================================================
ty_asis              04-14-86 10:05am       4 $00004       4 $00004      Asis 
ty_comp              05-10-88 05:41am    4081 $00FF1      50 $00032  98% Comp 
ty_crnc              05-14-87 06:33pm    3562 $00DEA    1893 $00765  46% Crnch
ty_sqz               05-14-87 04:32pm    8192 $02000    5748 $01674  29% Sqz  
===============================================================================
Files (4)                               15839 $03DDF    7695 $01E0F  51%      
Controls/overhead                                       1044 $00068
Total                                   15839 $03DDF    7799 $01E77  50%      
Savings                                                 8040 $01F68  31%      


     "Name" is the name of the file.

     "Date  time" is the date/time the file was last modified, NOT the
     time when it was added to the PAK.

     "orig length" is the original file length in deciaml and hex.

     "out length" is the file length in decimal and hex as saved within 
     the PAK.

     "action" various messages or percentage saved and method used to
      save file.

         Asis           No compression.
         Comp           Runs of repeated byte values are commpressed.
         Sqz            Huffman squeeze technique employed.
         Crnch          Lempel-Zev compression technique employed.

     Some totals are printed at end and are self explanitory.















     PAK                                                           Page 0006






     BACKUP

     When PAK changes an PAK (during an Add, Move, Update, Remove)
     it builds a new PAK with the same name, but with an extension 
     of ".TMP". 

     When PAK is finished it deletes the original and renames the
     temp PAK to the original name (TEST.PAK goes away, and TEST.TMP
     becomes the new TEST.PAK).  Among other things, this means that
     if anything goes wrong and PAK is unable to finish, then your
     original PAK will still be intact.

     If you wish to retain the original version of the PAK as a backup
     copy.  You can do this easily by using the Backup option.  Add
     the letter "B" to your command, and PAK will rename your original
     PAK to have an extension of ".BAK" instead of deleting it.

        pak ab test junk



     SUPPRESS COMPRESSION

     By adding a "S" to the Add, Move or Update commands PAK will store
     files "ASIS" without analyzing data.  This save considerable time
     if you just want to store files quickly.

































     PAK                                                           Page 0007






     MODIFICATIONS TO PAK

     A word about version and level numbers.  Version is a two digit number
     left of the decimal point and indicates a major revision such a new
     packing formula. Level is a two digit number right of the decimal point.
     The first decimal place (tenths) indicates a minor revision correcting 
     small problems. The second decimal place (hundredths) indicates a trival 
     revision for cosmetic (spelling etc.) type changes.

     Version 01 level 00.
       
     Original release of PAK.

     Version 01 level 10.
     
     Correct long int compiler problem if file greater than 64k.    
     All storage methods compatible with previous release.
     
     Version 01 level 20.

     Correct unaccessable file problem when move option has error.    
     Correct output file ending up in current directory even if full       
     pathname given.
     Redo calculation for ASIS storage.
     Date-last-modified on extracted file same as stored date.
     All storage methods compatible with previous releases.

     Version 02 level 00.

     Added Lempel-Zev compression formula.
     Added "S" option.
     Files stored asis if all formulas less than 5%.
     Version 02 will unPAK all version 01 files.
     Version 01 will ***NOT*** unPAK version 02 files.

























     PAK                                                           Page 0008