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PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 1
Table of Contents
-----------------
Topic Page
----- ----
Features and Overview .............................. 2
Archive Functions
Add files to an archive ........................ 4
Update files to an archive ..................... 4
Freshen files in an archive .................... 4
Move files to an archive ....................... 5
Delete files in an archive ..................... 5
Verbose listing of files in an archive ......... 5
PKARC Archive Commenting Feature ................... 6
Using a Ramdisk with PKARC ......................... 8
Using PKARC in a batch file ........................ 8
PKARC Error Messages ............................... 9
PKARC Revision history ............................. 11
General Information ................................ 12
Software License ................................... 13
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 2
Features
--------
- THE FASTEST CREATION AND UPDATING OF ARCHIVES - EVER.
- Highest compression ratios with state-of-the-art Enhanced
Dynamic Ziv-Lempel-Welch Crunching and Squashing.
- Unique Archive Commenting capability.
- Data integrity ensured by 16 bit Cyclic Redundancy Check.
- Superior file buffering.
- Not copy protected.
- Pay only if you find the software useful.
Overview
--------
An archive is a collection of one or more files collected into a
single archive file. A file extension of .ARC is usually used to
denote an archive. Each file in an archive is compressed to save
disk space, backup storage space, and file transfer time. When a
file is archived, it is analyzed and compressed with the most
optimal data compression method for that file. Every file in an
archive is stored with a 16-bit Cyclic Redundancy Check (CRC) to
ensure data integrity when the file is extracted from the archive.
PKARC is a FAST! archive update/create utility that generates
archives. It is compatible with SEAware's (Software Enhancement
Associate's) ARC program and my own FAST! archive extraction
utility PKXARC, but is many times faster than SEAware's ARC program
and faster than ANY OTHER archive utility. PKARC achieves its
speed through the use of highly optimized assembly language code
and advanced file buffering techniques. With version 1.1 of PKARC,
an Enhanced Ziv-Lempel-Welch crunching technique is employed which
can result in an up to a 40% space savings over ARC. With version
2.0 of PKARC, a new compression method called "squashing" is used
which can save up to an additional 10% or more for large text files.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 3
Using PKARC
-----------
Usage: PKARC [compatibility options] options archive [filespec...]
Compatibility options are:
/oc = old crunching (no squashing)
/ot = old datestamping method
/otc = both old crunching and datestamping
Options are:
a = add files to archive d = delete files from archive
f = freshen files in archive m = move files to archive
u = update files in archive v = display verbose listing of archive
l = display software license c = add/update file comments
x = add/update archive comment
The /oc compatibility option prevents PKARC from using file
squashing. With squashing disabled, PKARC will create archives
completely compatible with SEAware's ARC program and older versions
of PKXARC.
The /ot compatibility option forces PKARC to follow SEAware's
archive datestamping method. By default, PKARC sets the time and
date of an archive to the current time and date whenever it is
modified. The SEA archiver will set the time and date of an
archive to the time and date of the latest file within the archive.
Using this option will cause PKARC to use this archive dating
method.
The two compatibility options can be specified at the same time by
using either /oct or /otc.
The A,F,M, and U options can be followed by a C and/or X to cause
prompting for the file comments and/or the archive comment. The V
option can be followed by a C for a verbose listing with the file
comments.
The DOS wildcards * and ? can be used when specifying file names.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 4
Adding files to an archive
--------------------------
This option is used to add files to an existing archive, or create
a new archive with the specified files. This is the most common
use of PKARC. If no list of files is given, all the files in the
current directory will be added. Examples:
PKARC a stuff
will collect all the files in the current directory, and place them
in the archive STUFF.ARC
PKARC a a:manuals b:*.doc b:*.txt
will collect all files with an extension of .DOC or .TXT on drive B
and place them in the archive A:MANUALS.ARC.
Updating files to an archive
----------------------------
This option works the same as the Add option, with the exception
that if a file already exists within an archive, it will be updated
only if the datestamp of the file on the disk is dated after the
file within the archive. This option can be used to prevent an
earlier version of a file from overwriting a later version which is
in an archive. For example:
PKARC u manuals *.doc *.txt
will collect all files with an extension of .DOC or .TXT and place
them in the archive MANUALS.ARC. If however, a file already exists
in the archive and on the disk (say STARTREK.DOC), the file
STARTREK.DOC will be added to the archive only if it is dated later
than the version already in the archive. If the file on the disk
has an earlier date, then the version in the archive will remain.
Freshening files in an archive
------------------------------
This option is used to ensure that an archive contains all the
latest versions of its files. The Freshen function works like the
Update function, except it will not cause new files to be added to
the archive. For example:
PKARC f arcutil b:*.*
will go through all the files on drive B and look for files that
are in already in the archive, but with a later date. If a later
version is found, it will be updated in the archive.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 5
Moving files to an archive
--------------------------
This option works exactly like the Add function, except that the
original files are deleted from the disk after successful
archiving. The files are deleted only after the archive is created
and completed, and no errors have occurred. If any errors occur
during the archiving process (such as disk full) the original files
will not be deleted. For example:
PKARC m cfiles *.c
will add all files with an extension .C to the archive CFILES.ARC.
After all the files have been successfully added to the archive,
they will be deleted from the disk.
Deleting files from an archive
------------------------------
This option is used to delete files from within an archive. For
example:
PKARC d games *.bas
This will delete all files with the extension .BAS from the archive
GAMES.ARC.
Verbose listing of an archive
-----------------------------
This option is used to list the contents of an archive. The
listing is in the following format:
Filename Length Method Size Ratio Date Time
-------- ------ ------ ------ ----- ---- ----
FILENAME.EXT nnnnnn aaaaaaaa nnnnnn nn% mm-dd-yy hr:mm:ss
The length is the true length of the file. The method is the data
compression technique used on the file and is one of the following:
Stored The file was Stored.
Packed The file was Packed with non-repeat packing.
Squeezed The file was Squeezed with Huffman encoding.
crunched The file was crunched with old style Ziv-Lempel-Welch compression.
Crunched The file was Crunched with Dynamic Ziv-Lempel-Welch compression.
Squashed The file was Squashed with Dynamic Ziv-Lempel-Welch compression.
The size is the resulting size of the file after compression, and
the ratio is the percentage of file space saved. For example, a
file with a length of 10,000 and a size of 2,500 would have a
savings ratio of 75%.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 6
PKARC Archive File Comments Feature
-----------------------------------
One of the unique features of PKARC is the ability to store a
comment with an archive, and optionally a comment for each file in
an archive, similar to the file descriptions found on many Bulletin
Board Systems. The archive comment is automatically displayed when
the archive is manipulated by PKARC version 1.2 or later and PKXARC
version 3.3 or later. Each file in an archive can be given a
comment which can be displayed with the verbose listing function.
Following the V option with letter C will cause the comments to be
displayed. For example:
PKARC vc utility
will display the files in the archive UTILITY.ARC with the archive
file comments in the following format:
Filename Comment Date Time
-------- -------------------------------- ---- ----
FILENAME.EXT cccccccccccccccccccccccccccccccc mm-dd-yy hr-mm-ss
The archive comment and file comments can be up to 32 characters in
length.
If the A,U,F, or M options are followed by a X, prompting will
occur for the archive comment. For example:
PKARC ax datafils *.dat
will add all files with an extension .DAT to the archive
DATAFILS.ARC and prompt for the archive comment for DATAFILS.ARC.
If the A,U,F, or M options are followed by a C, prompting will
occur for a file comment after each file is added to the archive.
For example:
PKARC ac datafils *.dat
will add all files with an extension .DAT to the archive
DATAFILS.ARC. After each file is placed into the archive, the
comment for that file can be entered.
The C and X options from above can be combined to prompt for the
archive comment and the file comments at the same time. For
example:
PKARC acx datafils *.dat
will add all files with an extension .DAT to the archive
DATAFILS.ARC and cause prompting for the archive comment and the
file comments.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 7
The C option can be used to add or update file comments. For
example:
PKARC c programs
will go through all files in the archive PROGRAMS.ARC and prompt
for a comment for each file. Comments can be updated selectively,
such as:
PKARC c programs spoolkey.sys
will allow the file comment for the specified file to be added or
changed.
The X option can be used to add or update the archive comment. For
example:
PKARC x programs
will add or update the archive comment for the archive PROGRAMS.ARC.
The C and X options from above can be combined to prompt for the
archive comment and the file comments at the same time. For
example:
PKARC cx programs
will add or update the archive comment and the file comments for
the archive PROGRAMS.ARC.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 8
NOTE: The comments are stored in a way totally transparent to
SEAware's ARC program and and have no effect on the operation
of ARC.
However, because SEAware's ARC program does not know about
archive comments or file comments, ARC truncates the comments
from an archive when modifying it. Using SEAware's ARC
program to add, update, move, freshen or delete files from an
archive will cause all comments to be lost. If you wish to
retain the comments within an archive, it is recommended that
the use of SEAware's ARC program be avoided.
Using a Ramdisk with PKARC
--------------------------
PKARC sometimes creates one or two temporary files while archiving
files. The default drive for these files is the current drive. In
order to increase performance, PKARC can be told which drive and/or
subdirectory to use for temporary files through DOS environment
strings. PKARC searches the environment for the string
PKARCTMP=pathspec. For compatibility with ARC, the string
ARCTEMP=pathspec can be used as well. For example if drive D is a
ramdisk, entering:
SET PKARCTMP=D:
at the DOS prompt will cause PKARC to use drive D for temporary
files.
Using PKARC in a batch file
---------------------------
If you are using PKARC from a batch file, you can test if PKARC
aborted with an error using the DOS errorlevel variable. PKARC
returns a non-zero errorlevel if an error occurred, and a zero
errorlevel for normal termination.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 9
PKARC Error Messages
--------------------
When any of the following errors are detected, PKARC will display
the indicated message and abort to DOS. All original files and
archives will be intact, as PKARC does not overwrite or delete
existing files on the disk until the entire archive processing has
been successfully completed.
PKARC: Unknown option: (unknown character)
The displayed option is unknown.
PKARC: Insufficient Memory
There is not enough free memory to run PKARC.
PKARC: No archive specified.
The name of the archive to be processed must be given.
PKARC: No files specified for deletion.
The delete option was specified, but no files were given.
Unlike other options, delete does not assume *.* if no specific
files are given.
PKARC: Can't find XXXXXXXX.YYY
The specified file(s) could not be found.
PKARC: No file(s) found.
No files were found to add or update to the archive.
PKARC: Can't create file XXXXXXXX.YYY
The displayed file could not be created. The output directory
is probably invalid or full.
PKARC: Too many files.
This error will occur if more than 512 files or 16 different
drive/pathspecs are given at one time for the add, update,
freshen, or move options. While there is no limit on the total
number of files allowed in an archive, only 512 can be added at
one time.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 10
PKARC: XXXXXXXX.YYY is not an archive.
The archive name given to PKARC existed on the disk, but either
is not an archive, or is corrupted.
PKARC: Can't open XXXXXXXX.YYY
The displayed file could not be opened.
PKARC: disk full
The disk is full.
PKARC: XXXXXXXX.YYY is read-only!
The displayed archive file is a read-only or system file.
No modification (add, update, delete, etc.) is possible.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 11
PKARC Revision History
----------------------
*** PKARC version 1.0, 8-06-86 ***
Initial release.
*** PKARC version 1.1, 9-12-86 ***
Enhanced Ziv-Lempel-Welch compression was added to PKARC. The
enchanced crunching algorithm provides superior compression ratios
over the traditional crunching algorithm used in SEAware's ARC
program. Files crunched with the enhanced crunching algorithm are
up to 40% smaller, yet still fully compatible with ARC and PKXARC.
File buffering has been drastically improved, resulting in faster
compression, especially on floppy disks.
The improved buffering and other optimizations have resulted in a
twofold increase in archiving speed over PKARC version 1.0.
*** PKARC version 1.2, 10-23-86 ***
PKARC version 1.1 inadvertently introduced a rare bug involving
squeezed files. This has been corrected in version 1.2.
Archive commenting ability has been added to PKARC. PKARC now
allows a comment to be assigned to an archive, in addition to each
file within an archive. The archive comment is automatically
displayed when the archive is manipulated by PKARC version 1.2 or
later and PKXARC version 3.3 or later.
File buffering has been improved. While PKARC will still run in
minimum of 128K of RAM, PKARC will take advantage of up to 224K of
RAM if available to increase file buffering.
The Enhanced Ziv-Lempel-Welch compression has been slightly
improved. Some files will compress up to 5% smaller than with
PKARC version 1.1. Binary files should experience the most
improvement.
Optimizations in PKARC version 1.2 have resulted in up to a 20%
increase in archiving speed over PKARC version 1.1.
*** PKARC version 2.0, 12-15-86 ***
A new compression method called "squashing" was added to PKARC
version 2.0. Squashing is a variation of Dynamic Ziv-Lempel-Welch
compression which can yield a significant improvement over
crunching for larger text files. Also, the unsquashing of files is
faster than uncrunching. In addition, the Dynamic Ziv-Lempel-Welch
crunching has been improved in PKARC version 2.0 with some files
crunching significantly smaller than with PKARC version 1.2.
As always, minor speed improvements have resulted in about 10%
speed increase over the previous version.
An "old compatibility switch" was added to PKARC version 2.0 for
compatibility with SEAware's archive dating method. By default,
PKARC sets the time and date of an archive to the current time and
date whenever it is modified. The SEA archiver will set the time
and date of an archive to the time and date of the latest file
within the archive. While most users prefer that an archive date
be set to the current date, this switch was added for those who
prefer the SEA method.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 12
General Information
-------------------
PKARC will run on any IBM PC/XT/AT/RT/jr/Portable/Convertible or
DOS compatible whatever running PC/MS-DOS 2.0 or higher with a
minimum of 128K free RAM.
IBM is a registered trademark of the International Business Machine
Corporation.
MS-DOS is a registered trademark of Microsoft Inc.
If you have any questions or comments about PKARC send them to Phil
Katz at:
Exec-PC multi-user IBM BBS, Bob Mahoney SYSOP
Shorewood, Wisconsin
414-964-5160
300/1200/2400 baud, 24 hours a day, 16 lines
or
RBBS-PC of FARGO, Loren Jones SYSOP
Fargo, North Dakota
701-293-5973
300/1200/2400 baud, 24 hours a day
Special thanks to Bob Mahoney, Alan Losoff, Gene Alm,
Loren Jones, and Mike Shawaluk.
PKARC FAST! Archive Create/Update Utility Version 2.0 12-15-86 Page 13
License
-------
Copyright (c) 1986 PKWARE, Inc. All Rights Reserved.
You are free to use, copy and distribute PKARC providing that:
NO FEE IS CHARGED FOR USE, COPYING OR DISTRIBUTION.
IT IS NOT MODIFIED IN ANY WAY.
Clubs and user groups may charge a nominal fee for expenses and
handling while distributing PKARC.
Volume discounts, site licenses, commercial licenses and custom
versions of PKARC and PKXARC are available. Write to the address
below for more information.
This program is provided AS IS without any warranty, expressed or
implied, including but not limited to fitness for a particular
purpose.
If you find PKARC fast, easy, and convenient to use, a contribution
of $20 would be appreciated. With each contribution of $45 or more
you will be registered to receive a diskette with the next version
of PKARC and PKXARC when available. Please state the current
versions of PKARC and PKXARC that you have. Send contributions to:
PKWARE, Inc.
7032 Ardara Avenue
Glendale, WI 53209