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.