7gmadiso@pomona.bitnet.UUCP (04/07/87)
XARC4/CMD
File Archive Utility
Version 01.00.00 02/14/87
for TRSDOS 6.x.x
(C) COPYRIGHT 1985, 1986 by System Enhancement Associates;
ALL RIGHTS RESERVED
TRSDOS 6.x.x adaptations (C) COPYRIGHT 1987 by David Huelsmann;
ALL RIGHTS RESERVED
This document describes the XARC4 file utility, version 01.00.00, which was
based on the MS-DOS ARC created by System Enhancement Associates.
INTRODUCTION
XARC is the copyrighted property of System Enhancement Associates. Since
XARC4 is a derivative work based on XARC, it, too, is the copyrighted property
of System Enhancement Associates. The TRSDOS 6.x.x modifications are the
copyrighted property of David Huelsmann. You are granted a limited license to
use XARC4, and to copy it and distribute it, provided that the following
conditions are met:
1) No fee may be charged for such copying and distribution.
2) XARC4 may ONLY be distributed in its original, unmodified state.
Any voluntary contributions for the use of this program will be appreciated,
and should be sent to:
System Enhancement Associates
21 New Street
Wayne, NJ 07470
You may not use this product in a commercial environment or a governmental
organization without paying a license fee of $35. Site licenses and commercial
distribution licenses are available. See the order form in the back of this
manual for more details.
A word about user supported software:
The user supported software concept (usually referred to as freeware) is an
attempt to provide software at low cost. The cost of offering a new product by
conventional means is staggering, and hence dissuades many independent authors
and small companies from developing and promoting their ideas. User supported
software is an attempt to develop a new marketing channel, where products can
be introduced at low cost.
If user supported software works, then everyone will benefit. The user will
benefit by receiving quality products at low cost, and by being able to "test
drive" software thoroughly before purchasing it. The author benefits by being
able to enter the commercial software arena without first needing large sources
of venture capital.
But it can only work with your support. We're not just talking about XARC
and XARC4 here, but about all user supported software. If you find that you are
still using a program after a couple of weeks, then pretty obviously it is
worth something to you, and you should send in a contribution.
And now, back to XARC4:
XARC4 is used to extract files from MS-DOS archives or from ARC4 created
archives. An archive is a group of files collected together into one file in
such a way that the individual files may be recovered intact.
When XARC4 is used to extract files from an archive, it extracts files
created by ARC4 or MS-DOS ARC version 5.0 to 5.1.2 that utilized any of four
possible storage methods. These four methods are:
1) No compression; the file was stored as is.
2) Repeated-character compression; repeated sequences of the same byte value
were collapsed into a three-byte code sequence.
3) Huffman squeezing with repeated-character compression; the file was
compressed into variable length bit strings, similar to the method used by
the SQ programs.
4) Dynamic Lempel-Zev compression; the file was stored as a series of variable
size bit codes which represent character strings, and which were created "on
the fly".
Note that since one of the four methods involved no compression at all, the
resulting archive entry is never larger than the original file.
USING XARC4
XARC4 is invoked with a command of the following format:
XARC4 <x> <arcname> <arcname> . . .|
Where:
<x> is an XARC4 command letter (see below), in either upper or lower
case.
<arcname> is the name of the archive to act on, with or without an extension.
If no extension is supplied, then "/ARC" is assumed. The archive name
may include a drive specifier even if the extension is not supplied.
If XARC4 is invoked with no arguments (by typing "XARC4", and pressing
<ENTER>, then a brief command summary is displayed.
The following is an example of the display when XARC4 is invoked with no
arguments:
XARC4/CMD Version 01.00.00 02/14/87
(C) COPYRIGHT 1985,1986 by System Enhancment Associates
ALL RIGHTS RESERVED
TRSDOS 6.x.x adaptations (C) COPYRIGHT 1987 by David Huelsmann
ALL RIGHTS RESERVED
Distributed with permission of SEA
Usage: XARC4 o:xnlv| g<password>| arcname arcname. . .|
Where:
o:x = Output drive (x = 0 to 7)
n = New Line Mode: Suppress removing LF after CR
l,v = List table of contents (verbose) to CRT
g = Garble (decrypt) archive entry
If no extension is given, then /ARC is assumed.
Refer to program documentation for complete instructions
and limitations on copying and distribution of this program.
XARC4 COMMANDS
This section describes each of the commands. ARC4 will accept any one ommand
at a time. If no commands are given, then a brief command list is displayed as
shown above.
EXTRACTING FILES
Archive entries are extracted when the output drive specifier is added to
the command line. Note that ALL files are extracted. There is no provision in
XARC4 to let you specify a specific file. Also note that you can place as many
archives on the command line as can fit and the files will be extracted from
each archive in order. ALL will be placed on the output drive specified - that
is, only one ouput drive may be specified no matter how many archives are
listed on the command line.
You could type:
XARC4 O:2 JUNK:1
or
XARC4 O:2N JUNK
Note that in the first example, the files would be extracted to drive 2. In
the second example, the files would also be extracted to drive 2 and automatic
removal of Line Feeds after Carriage Returns would be suppressed. In addition,
the first occurrence of JUNK/ARC would be used starting with drive 0.
Whatever method of file compression was used in storing the files is
reversed, and uncompressed copies are created. If a file with the same name
already exists on the drive specified, you will be asked if you wish to
overwrite the file.