575 lines
28 KiB
Plaintext
575 lines
28 KiB
Plaintext
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SHRINKIT FOR THE APPLE IIGS
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Program by Andy Nicholas
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Documentation by Karl Bunker
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Send comments/suggestions on ShrinkIt to:
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Andy Nicholas
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1180 Reed Ave, Apt 12
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Sunnyvale, CA 94086
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Electronic Addresses:
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GEnie, America-Online: shrinkit
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Compuserve: 70771,2615
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Internet: shrinkit@apple.com
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Note: In online discussions, GS-ShrinkIt is often abbreviated "GSHK".
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Send comments/suggestions on this documentation file to:
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Karl Bunker
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GEnie: k.bunker
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What is GS-ShrinkIt?
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--------------------
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GS-ShrinkIt is a utility program for archiving files and disks.
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"Archiving", in this usage, refers to the process of placing files or
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disks "within" another file -- the archive file. This is usually done
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to prepare the files/disks for transmission via modem, or for storage
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purposes. Thus, an archive file, whether created with GS-ShrinkIt or
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another archiving utility, will be a file which serves as an envelope,
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containing one or more other files, or complete disks. There are a
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number of reasons for archiving files before transmitting them with a
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modem. The principal reason is that an archive provides a means of
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sending the "attributes" of a file -- its filetype and other
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information -- along with the file itself. An archive also allows
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several related files (or an entire disk) to be packed together into a
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single file. True archiving utilities will also have the capability of
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compressing the files they contain to minimize the transmission time
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and disk space the archive requires.
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GS-ShrinkIt uses a highly efficient compression algorithm known
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as dynamic LZW, and creates archive files with a format called NuFX.
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GS-ShrinkIt and the 8-bit version of ShrinkIt are currently the
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standard archiving utilities for Apple II telecommunications.
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GS-ShrinkIt can unpack files which have been archived with
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GS-ShrinkIt, as well as those which have been packed with certain
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other Apple II file-packing utilities, such as BLU and ACU. One of
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GS-ShrinkIt's most exciting features is that it can also unpack a
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variety of non-Apple II archives. This will be discussed in more
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detail later in these instructions.
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About These Instructions
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------------------------
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Most users of GS-ShrinkIt will be interested in unpacking files
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that they have downloaded from a Bulletin Board Service or Information
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Service. Others will also be using it to pack files that they want to
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upload to such a service. In these instructions I will first describe
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how one uses GS-ShrinkIt to unpack archives, and then how to create a
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new archive file. Then I will give an explanation of each of the
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options available in GS-ShrinkIt's pull-down menus. If you are ONLY
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interested in how to unpack a file which you have downloaded, you can
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read as far as the end of the section entitled "Unpacking an Archive",
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and skip the latter sections. I will attempt to make these
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instructions understandable to the relatively new computer-user; if
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you are unfamiliar with any of the terms used, or become generally
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confused, you may want to consult the instruction manual to your
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telecommunications software, or a magazine article on
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telecommunicating with the Apple II.
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System Requirements
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-------------------
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GS-ShrinkIt requires a IIgs with System Disk 5.02 or later, and a
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minimum of 768K of RAM. If you are using a GS/OS program launcher
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other than the Finder, it's possible that your system (boot) disk
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doesn't have an "Icons" folder. GS-ShrinkIt requires that you have
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this folder on your system disk, and that it contain (at least) the
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file "FType.Main".
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GS-ShrinkIt and ShrinkIt
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------------------------
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GS-ShrinkIt is (of course) for the Apple IIgs. There are also
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versions of ShrinkIt available for 8 bit Apple II's. Archives created
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with GS-ShrinkIt can be unpacked with version 3.0.3 or later of the 8
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bit ShrinkIt, providing that none of the files being extracted from
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the archive is an "extended" GS/OS file (also know as files with
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resource forks). Since ProDOS-8 can't handle extended GS/OS files,
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someone who doesn't own a IIgs would probably have no reason to
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extract such a file.
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Distribution and Copyright Info
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-------------------------------
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GS-ShrinkIt is a Freeware program. This means that you are under
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no obligation to pay the author anything for it, but the copyright is
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retained by him. You are encouraged to distribute this program to
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whomever you please.
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Some Terms Defined
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------------------
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In the Apple II telecommunications community, there are a number
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of different file- and disk-packing formats which have been used over
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the years. Most of these formats have been superseded by ShrinkIt and
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its NuFX format, others are still used. These various formats are
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usually denoted with a three-letter suffix appended to the file's name
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(as in "MY.FILE.BNY"). The following is a list of the suffixes you are
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likely to encounter, with brief descriptions of their related file
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formats:
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.BNY: Binary II format. Though not a true archive format, a Binary II
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"envelope" will preserve a file's attributes through a download
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or upload. GS-ShrinkIt can unpack .BNY files, and they can
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also be automatically unpacked during downloading by many
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telecommunications programs.
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.BQY: "Squeezed" (i.e., compressed with a different algorithm than the
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one used by GS-ShrinkIt) files within a Binary II envelope.
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Created with the utility BLU, these files can be unpacked with
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GS-ShrinkIt.
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.QQ: If you remove the Binary II envelope from a .BQY file, the
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squeezed files it contains will have the suffix .QQ. These files
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can be unsqueezed with GS-ShrinkIt.
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.ACU: The archive format used by America Online (formerly
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AppleLink Personal Edition); these files can be unpacked with
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GS-ShrinkIt. (America Online currently uses .SHK format for new
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uploads.)
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.SHK: NuFX format; can be created and unpacked with GS-ShrinkIt.
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.BXY: A NuFX archive within a Binary II envelope. This is the format
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currently required for new uploads to the Apple II libraries of
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GEnie and Compuserve. .BXY files can be created and unpacked
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with GS-ShrinkIt. Although this "envelope within an envelope"
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format may seem redundant, it has several advantages. Ideally,
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the Binary II envelope will be entirely "transparent" to end
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users -- it will be automatically added by telecommunications
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software during uploading, and automatically removed during
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downloading. As more telecommunications programs come to support
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automatic Binary II packing and unpacking, this ideal will be
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increasingly realized. Thus, if your telecommunications software
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supports automatic Binary II unpacking during downloading, you
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can turn this option on when downloading a .BXY file. Doing this
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will give you a downloaded file which is a "bare" NuFX archive.
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Thanks to the Binary II wrapper, this file will automatically be
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given the correct name and filetype.
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Unpacking an Archive
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--------------------
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GS-ShrinkIt uses the standard Apple Desktop interface commonly
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found in IIgs programs, with the familiar pull-down menus and dialog
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boxes.
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When you have downloaded a file with one of the suffixes given
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above, you will want to process this file through GS-ShrinkIt to
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unpack it and get at the files or disks it contains. It doesn't matter
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which of the packing formats your download is in; GS-ShrinkIt will
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automatically recognize the format and handle the file accordingly. To
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unpack an archive, you select "Open Archive..." from the "File" menu.
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This will give you an "Open which Archive?" file-selection dialog box.
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In addition to the usual "Disk", "Open", "Close" and "Cancel" mouse
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buttons, there are also two radio buttons labeled "Show Only Archives"
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and "Show All Files". GS-ShrinkIt uses two methods to decide whether a
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file is an archive file: It checks the attributes of the file (its
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filetype and auxtype), and it checks to see if the filename has an
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appropriate suffix. When a file is downloaded, its attributes may not
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be preserved through the download.If your archive doesn't have EITHER
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the appropriate attributes OR a suffix that GS-ShrinkIt recognizes,
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GS-ShrinkIt won't be able to identify that file as an archive. If you
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don't see your archive file listed in the window (after you've opened
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the appropriate folder), try clicking the "Show All Files" button.
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(A bug in System 5.0.2 sometimes causes the file dialog to hang
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if it can't find a disk which it expects to be online. To avoid this,
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you should only swap disks in your drives AFTER the file dialog is
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on-screen.)
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When you click the "Open" button with your file highlighted, a
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window will be displayed showing what type of archive file you have
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selected, and listing the "items" (the packed files or disks)
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contained within the archive. This window will also show several
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buttons: "Extract", "Info", "Delete", "Sort", "Add Files", and "Add
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Disk". If you simply want to unpack this archive, only "Extract" and
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"Info" need concern you.
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If the archive is NuFX format, there may be a brief message
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included within the archive by the person who put it together and
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uploaded it. Items which have space set aside for an attached message
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will have a small document icon to the right of the item's name. If
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there is an actual message, this icon will be yellow; if the message
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space is blank, it will be gray. You can read the message by
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highlighting the item and then clicking the "Info" button. This will
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display a window with various pieces of information about that item,
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and the message text, if there is any.
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To unpack an archive, you must first highlight those items which
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you want to extract. Usually you will want to extract all of the items
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listed, but you also have the option of extracting only one or a few
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items. To highlight all of the items, press Apple-A. You can select
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several individual items by holding down the Apple key while you click
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on those items you want. You can select a group of items by holding
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down the shift key and clicking on the first item in the group you
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want, and then on the last of the group.
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When the items you want are highlighted, click the "Extract"
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button. Another file-selection dialog box will be displayed allowing
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you to choose which disk and folder you want to put the new, unpacked
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files in. Open the appropriate folder, and click the "Accept" button.
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If there is a file in the folder with the same name as the file you
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are about to unpack, GS-ShrinkIt will ask if you want to overwrite the
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existing file, rename the unpacked file, skip that file, or cancel.
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You can set GS-ShrinkIt to automatically overwrite any existing
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same-name files by turning off the "Prompt before overwriting" check
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box which appears in the file-selection dialog.
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If the archive file contains a packed disk (or disks),
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GS-ShrinkIt will prompt you to select a "device" (disk drive) for the
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archived disk to be unpacked to.
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Creating an Archive
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-------------------
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As you might expect, creating an archive is somewhat more
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involved than unpacking one. However, the process is quite
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straightforward.
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If you are going to be archiving files (rather than a disk),
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select "New File Archive..." from the "File" menu. A file-selection
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dialog box will be displayed, allowing you to select the files to be
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archived. There are two check boxes in this file-selection dialog box;
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these let you choose whether to "Use Compression" (usually you will
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want to compress the files you archive) and to "Delete after
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archiving".
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As when selecting items to be extracted from an archive,
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GS-ShrinkIt gives you several ways to highlight files in this dialog
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box. You can select all the files in the open folder by clicking the
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"Select all" button, you can select several individual files by
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holding down the Apple key while you click files, and you can select a
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group of files by holding down the shift key and clicking on the first
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and last files of the group.
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When the files you want to archive are highlighted, click the
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"Accept" button. A new file-selection dialog box will appear,
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prompting you for a "Destination Name" -- a filename for the archive
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file you are about to create. After opening the disk and folder you
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want your archive to be saved to, enter a name for the archive in the
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text box. To avoid confusion, be sure the filename has the correct
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suffix: Straight NuFX archive should have the suffix ".SHK", and
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NuFX-within-Binary-II archives should be suffixed ".BXY". After
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entering the filename, press <return> or click the "Save" button, and
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the archive will be created.
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There is a check box in the "Destination Name?" dialog box
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labeled "Save as '.BXY' file". This box must be checked if you want
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your archive to be saved to disk in the NuFX-within-Binary-II format.
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The best way to create a .BXY file is to use GS-ShrinkIt to make
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a .SHK file, and then let your telecommunications program add the
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outer Binary II envelope during uploading. However, not all
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telecommunications programs can do this. GS-ShrinkIt does not allow
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you to add new items to a .BXY archive after it has been created. This
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can only be done with "bare" NuFX archives. For this reason, if you
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are using GS-ShrinkIt to make a .BXY file, you must start out with all
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of the files you want to archive in the same folder, so you can select
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and pack them all at once.
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After creating a new archive, you can perform a number of
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operations on it. You can delete items, you can add a file or disk
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item (provided the archive isn't a .BXY file), you can sort the
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archive to change the order in which its items are listed, and you can
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add a short message to the archive to be read when the "Info" button
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is clicked. All of these operations are performed via the "Open
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Archive..." option in the "File" menu; that is, you must first select
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and open the archive, just as you would if you were going to unpack
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it.
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To add a message, or "comment" to an archive, you first highlight
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the top item listed in the archive, and then click the "Info" button.
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Enter the text of your message in the lower half of the "Info on Item"
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window, and then click the "Update" button in that window.
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The other operations are performed by clicking the appropriate
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buttons in the Open Archive window. The various options for sorting
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items within an archive can be set in the "Preferences" dialog box,
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selected from the "Special" menu. This will be described later. The
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sorting operation requires an amount of free disk space equal to the
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size of the archive file. If GS-ShrinkIt doesn't find sufficient space
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on the currently open disk, it will report the problem and abort the
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operation.
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To create a new archive from an entire disk, you would select
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"New Disk Archive..." from the "Disk" menu. Disks to be archived may
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be ProDOS disks, or they may use other operating systems, such as DOS
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3.3, CP/M or Pascal. Some non-standard, "customized" operating systems
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can also be handled. Unfortunately, due to a bug in the IIgs 5.0.2
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System Disk, GS-ShrinkIt disk-archiving only functions correctly with
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3.5" disks and ProDOS 5.25" disks; non-ProDOS 5.25" disks cannot be
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archived or unpacked. To archive or unpack 5.25" disks, you will have
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to use the 8 bit version of ShrinkIt.
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Pull-down Menu Options
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----------------------
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The above instructions give a fairly thorough overview of
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GS-ShrinkIt. This section provides a list of each of the options
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available in GS-ShrinkIt's pull-down menus. This will serve as a
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reference section to the instructions, and will also fill in some
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details not dealt with above.
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"Apple" Menu:
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About ShrinkIt...
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Information about the programmer, distribution & copyright
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information, addresses for user support, thanks to those who
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helped out.
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Your NDA's are also under this menu.
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File Menu:
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New File Archive... (Apple-N)
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Create a new archive (from files).
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Open Archive... (Apple-O)
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Open an existing archive to unpack its contents or to modify
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it.
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Close (Apple-W)
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Close the active window.
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Delete...
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Delete files from your disks.
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Quit (Apple-Q)
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Exit from GS-ShrinkIt.
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Edit Menu:
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Undo
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Cut
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Copy
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Paste
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Clear
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These are provided for use when editing an archive message,
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and for possible use by NDA's.
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Select All (Apple-A)
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Select all files in the displayed folder, or all items in
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the displayed archive.
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Disk Menu:
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New Disk Archive... (Apple-D)
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Create a new archive from a disk.
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Erase...
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Erase the contents of a disk.
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Format...
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Format a disk. Due to a quirk in the ROM 03 IIgs firmware, the
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Format option will not work on this machine.
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Special Menu:
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Create AppleSingle...
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AppleSingle is a relatively simple file-packing format
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designed by Apple, Inc. to provide a means by which extended
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GS/OS files can be handled on "foreign" file systems (such as
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ProDOS 8). AppleSingle files can only contain one file, and
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don't use any compression. Because NuFX archives are also
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able to store extended GS/OS files, and have many other
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capabilities as well, most users will have no need for this
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option. GS-ShrinkIt can also unpack AppleSingle files, and
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AppleSingle within Binary II files.
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Preferences...
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This option puts up a dialog box with several check boxes and
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pop-up menus, allowing you to set a number of parameters.
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These settings will be saved in an "invisible" file called
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"ShrinkIt.Prefs" in the folder containing GS-ShrinkIt.
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The check boxes are as follows:
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Show invisible files
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Show invisible files (such as "Finder.Data") in
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file-selection displays.
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Prompt on every extraction
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When multiple items are selected for extraction from an
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archive, you will be prompted to select a new disk and
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folder for each file before it is unpacked.
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Force extracted names to fit ProDOS
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When extracting a file from one of the "foreign" archive
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formats (see below), the name of the file may not fit
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ProDOS's rules for filename syntax. With this box checked,
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GS-ShrinkIt will automatically modify such a filename to
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make it legal. If the box is unchecked, you will have to
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modify such filenames manually.
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Use sessions when archiving
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"Sessions", also referred to as "cache-deferred writes",
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are a feature of GS/OS which can save considerable time
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with disk-intensive operations, such as creating large
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archives. With "Use sessions" selected, the new archive
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will be saved in memory until the entire archive-creation
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process is completed (or until memory runs out). Then it
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will be written to disk. A disadvantage of using sessions
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is that it uses up memory which GS-ShrinkIt may need for
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its file compression process.
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Use sessions when extracting
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This option corresponds to "Use sessions when archiving"
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above, but enables the use of sessions when an archives are
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being unpacked.
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Attach suffix when archiving
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With this box checked, GS-ShrinkIt will automatically add
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the appropriate suffix -- either ".SHK" or ".BXY" -- to the
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default archive name it offers you.
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To the right of these check boxes there are eight labels
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with pop-up menus; the titles of these menus are:
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Sort by:
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This allows you to set how the items in an archive will
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be sorted when you click the "Sort" button. The choices
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are:
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Name (Alphabetical order)
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Length (Of the uncompressed file)
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Percent Size (How much the file was compressed)
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Date Archived
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Filetype
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Auxtype
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Sort order:
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Ascending
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Descending
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Comment size:
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This lets you set the maximum size of the comment that
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can be added to an archive; the choices are:
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100 Bytes
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200 Bytes
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400 Bytes
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800 Bytes
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1000 Bytes
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Add Comment to:
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First File
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All Files
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With First File (the default), a message can only be
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attached to the first item in an archive. This menu
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gives you the option of adding comments to all of the
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items.
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Archive As:
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Hierarchy
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Flat File
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It is possible to select a folder for archiving with
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GS-ShrinkIt. When you do this, the entire contents of that
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folder (including the contents of any folders within the
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folder you selected) will be archived. Normally, when this
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archived folder is unpacked, GS-ShrinkIt will first create
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the folder that was archived, and then extract the folder's
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contents, placing them within the new folder. By changing
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the "Archive As:" preference from "Hierarchy" to "Flat
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File", you can change this procedure. A "Flat File" archive
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will only contain the contents of any selected folders; it
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will not contain the folders themselves. Thus, when this
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archive is unpacked, no new folders will be created, and
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the archived files will simply be placed "flat" in whatever
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disk and folder you selected.
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Extract As:
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Hierarchy
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Flat File
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This option corresponds to the "Archive As:" preference
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above, but it controls how an archive is extracted, rather
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than created. With "Flat File" selected here, an archive's
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contents will be extracted "flat", with no new folders
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being created, even if that archive contains one or more
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folders.
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Save ARC Files As:
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Binary
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Text
|
|
Save ZOO Files As:
|
|
Binary
|
|
Text
|
|
"ZOO" and "ARC" are two "foreign" archive formats supported
|
|
by GS-ShrinkIt; this is discussed in more detail below.
|
|
These two options in the Preferences window allow you to
|
|
set how files which GS-ShrinkIt extracts from these
|
|
archives will be saved on your disk. The ZOO and ARC
|
|
archive formats don't include any internal information that
|
|
GS-ShrinkIt can use to determine what type the files should
|
|
be when they are extracted, so the user has to make this
|
|
decision.
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|
|
|
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|
"Foreign" Archive and Compression Formats
|
|
-----------------------------------------
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|
This part of the instructions was left for last because it's a
|
|
little technical. However, you shouldn't feel too intimidated even if
|
|
many of the terms used here are unfamiliar. The "short version" of
|
|
this section is simply this: Thanks to the remarkable versatility of
|
|
GS-ShrinkIt, IIgs users can now unpack MOST of the files found in MOST
|
|
of the download libraries of the online services. Whether these files
|
|
are for Macs, Atari STs, Amigas, IBM PCs, or Unix systems, there is a
|
|
good chance that GS-ShrinkIt will be able to unpack them. Although
|
|
programs which were written for these other computers will not run on
|
|
a IIgs, such things as text files, programmer's source code and
|
|
graphics files (which can be converted for IIgs viewing with utilities
|
|
such as SHR.Convert) CAN be used on the IIgs. It's probable that
|
|
certain other types of non-IIgs files will become usable on the IIgs
|
|
in the future. The wide range of formats supported by GS-ShrinkIt make
|
|
it the most versatile archiving utility available for ANY personal
|
|
computer. So take advantage of this and go exploring in those other
|
|
libraries!
|
|
What follows isn't intended to be a complete description of the
|
|
archiving and library standards used by these various other computers.
|
|
It only presents the salient points of using GS-ShrinkIt with the
|
|
archive formats it supports. The "foreign" (non-Apple II) formats
|
|
supported by GS-ShrinkIt are:
|
|
|
|
StuffIt (Used on the Macintosh)
|
|
ZOO (Used on the IBM PC, Amiga and Atari ST)
|
|
ARC (Used on the IBM PC, Amiga and Atari ST)
|
|
Compress (Used on computers running the Unix operating system)
|
|
|
|
StuffIt:
|
|
GS-ShrinkIt can extract files from StuffIt archives, sort them,
|
|
and delete items from them. Encrypted items can not be extracted,
|
|
nor can HFS folders within other folders. Such items will be
|
|
dimmed in GS-ShrinkIt's display. StuffIt archives within
|
|
MacBinary I or II "envelopes" are supported, as are StuffIt
|
|
archives from America Online.
|
|
ZOO:
|
|
ZOO archives can be opened and their contents extracted with
|
|
GS-ShrinkIt. ZOO archives can't be sorted or items within them
|
|
deleted, however.
|
|
ARC:
|
|
GS-ShrinkIt's unpacking of ARC archives works only for those
|
|
created with ARC 5.0, not ARC 6.0, which are less common. Some of
|
|
the types of compression used in ARC files are not supported, and
|
|
archive items using these methods will appear dimmed. Sorting and
|
|
deleting of ARC items is not supported.
|
|
Compress:
|
|
GS-ShrinkIt should be able to unpack all types of Unix Compress
|
|
files.
|
|
|
|
Two fairly common archive formats which are not currently
|
|
supported by GS-ShrinkIt are ZIP and LHArc (LZH). These formats are
|
|
used on IBM PCs and other machines.
|
|
|
|
Table of Supported Formats
|
|
--------------------------
|
|
For reference purposes, the following is a table showing all of
|
|
the file packing formats supported by GS-ShrinkIt:
|
|
|
|
Format |Filename
|
|
|Suffix
|
|
| |[C]reates and
|
|
| |Unpacks, or
|
|
| |[U]npacks Only
|
|
| | |
|
|
| | |Computer(s) Which
|
|
| | |Use This Format
|
|
--------------------------------|------|---|--------------------------
|
|
NuFX . . . . . . . . . . . . . | .SHK | C | Apple II
|
|
NuFX in Binary II . . . . . . . | .BXY | C | Apple II
|
|
Binary II . . . . . . . . . . . | .BNY | U | Apple II
|
|
Binary II in Binary II. . . . . | .BNY | U | Apple II
|
|
ACU (Used on America Online) . .| .ACU | U | Apple II
|
|
ACU in Binary II . . . . . . . | -- | U | Apple II
|
|
SQ (BLU) . . . . . . . . . . . | .QQ | U | Apple II
|
|
SQ in Binary II (BLU) . . . . . | .BQY | U | Apple II
|
|
AppleSingle . . . . . . . . . . | -- | C | Apple II
|
|
AppleSingle in Binary II . . . | -- | U | Apple II
|
|
StuffIt . . . . . . . . . . . . | .SIT | U | Macintosh
|
|
StuffIt in MacBinary I or II. . | .SIT | U | Macintosh
|
|
StuffIt from America Online . . | .SIT | U | Macintosh
|
|
Zoo . . . . . . . . . . . . . . | .ZOO | U | IBM PC, Amiga, Atari ST,
|
|
| | | Unix systems
|
|
ARC . . . . . . . . . . . . . . | .ARC | U | IBM PC, Amiga, Atari ST
|
|
Compress . . . . . . . . . . . | .Z | U | Unix Systems
|
|
|
|
|
|
For More Technical Information...
|
|
---------------------------------
|
|
If you want to know more about data compression:
|
|
|
|
Welch, T. A Technique for High-Performance Data Compression. IEEE
|
|
Computer, Vol. 17, No. 6, June 1984, pp. 8-19.
|
|
|
|
Ziv, J. and Lempel, A. A Universal Algorithm for Sequential Data
|
|
Compression. IEEE Trans. Information Theory, Vol. IT-23, No. 3, May
|
|
1977, pp. 337-343.
|
|
|
|
Ziv, J. and Lempel, A. Compression of Individual Sequences via
|
|
Variable-Rate Coding, IEEE Trans. Information Theory, Vol. IT-24, No.
|
|
5, Sept. 1978, pp. 5306.
|
|
|
|
Storer, James A. Data Compression: Methods and Theory. Computer
|
|
Science Press, 1988. ISBN 0-7167-8156-5.
|
|
|
|
Held, Gilbert. Data Compression, Techniques and Applications, Hardware
|
|
and Software Considerations. John Wiley & Sons, 1987
|
|
|
|
If you want to know more about the NuFX ("nu-eff-ex") archive format,
|
|
please consult the Apple Filetype Technote for $E0/$8002.
|
|
|
|
|
|
Trademarks
|
|
----------
|
|
Apple, Apple II, IIgs, GS/OS, ProDOS, Finder and Macintosh are
|
|
registered trademarks of Apple Computer Inc. ACU and AppleLink are
|
|
registered trademarks of Quantum Computer Services, Inc. America
|
|
Online is a registered service mark of Quantum Computer Services Inc.
|
|
StuffIt is a registered trademark of Aladdin Systems, Inc. and Raymond
|
|
Lau. ARC is a registered trademark of System Enhancement Associates,
|
|
Inc. Unix is a registered trademark of AT&T. ShrinkIt is a trademark
|
|
of Andrew E. Nicholas
|
|
|