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Mac OS 8.1 Delivers Under the Hood

Apple has released Mac OS 8.1, and the Macintosh community is buzzing with talk about the new components and trying to figure out the new (and optional) disk format, Macintosh Extended Format, also known as HFS Plus. We have an article about HFS Plus later in this issue, so here I’ll talk about what else is new in 8.1 and how to install it.

What’s New Besides HFS Plus? Mac OS 8.1 offers faster launch times and speedier copying to and from network volumes. There’s also a new control for Finder list views that reverses a window’s sort direction (handy for listing items from oldest to newest, for example). Less visibly, the Finder eliminates several memory leaks when using Apple events, so scripting the Mac OS 8.1 Finder is more robust.

Mac OS 8.1 also ships with support for new types of storage media: UDF (Universal Disk Format) CD-ROMs and DVD-ROM disks. To use a UDF formatted CD-ROM, you need at least a double-speed CD-ROM drive. No Macs have yet shipped with DVD-ROM drives, but E4 has reportedly demonstrated a CoolDVD PCI card that enables Macs to use external third-party DVD-ROM drives.


Mac OS 8.1 brings together a large collection of new (and recently new) system components. Those who swap files with Windows users will welcome PC Exchange 2.2, which supports Windows 95’s long file names and has greatly improved support for PC-based removable media and disk formats. A new SoundSource control strip module can quickly change a machine’s audio input source. The choices vary with your Mac’s hardware, but commonly include microphone and audio CD inputs, as well as "none," which can help prevent the Mac’s automatic monitoring of sound input from interfering with some audio software. Under Mac OS 8.1, applications also have greater control over audio input and output.

There’s also LaserWriter 8.5.1 (see "LaserWriter Edges Up to 8.5.1" in TidBITS-406), Open Transport 1.3 (see "Open Transport 1.3" earlier in this issue), Apple CD-ROM 5.4.2, AppleShare 3.7.4 and updates to built-in Ethernet drivers, Text Encoding Converter 1.3 (see below for more info), Monitors and Sound 1.3.3, and Macintosh Runtime for Java (MRJ) 2.0. Not every item is the most recent; for instance, Mac OS 8.1 contains the Apple Remote Access 2.1.1 client, but ARA 3.0 client and personal server are available commercially.


In the retail version, Apple is shipping Location Manager 2.0.1. The original version, which came with Mac OS 7.6.1, enabled PowerBook users to switch network, printing, and other settings between predefined sets. The new version also works on many desktop computers. Although it’s not in the Mac OS 8.1 Update, Location Manager 2.0.1 can be downloaded from Apple’s servers. Similarly, QuickDraw 3D 1.5.3 improves support for high-end graphics cards and is in the retail release of Mac OS 8.1 and on Apple’s servers, but is not included in the Mac OS 8.1 Update.


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Mac OS 8.1 also includes LocalTalkPCI, a PowerPC-native LocalTalk driver built for use under Open Transport. Although LocalTalkPCI eliminates lackluster LocalTalk performance on Apple’s new G3 systems, it can cause LocalTalk printers to disappear from the Chooser. If that happens, disable the LocalTalkPCI extension: you’ll lose the performance improvements, but be able to print.

Getting Mac OS 8.1 — Mac OS 8.1 is available in two forms. The first is an online update for owners of Mac OS 8 that can be downloaded for free. Apple has posted the update in BinHex and MacBinary versions, both as a large (15 to 22 MB) single file and as thirteen smaller files.


The second form is a retail Mac OS 8.1 CD-ROM, which will be available beginning in February for $19.95 to owners of Mac OS 8, and at normal retail prices through other outlets (expect prices from $65 to $100). Also in February, new Apple CPUs should ship with Mac OS 8.1 pre-installed.


The Mac OS 8.1 update works only on U.S. versions of Mac OS 8. Look for localized versions in April, though some versions may appear sooner.

System Requirements — Mac OS 8.1’s system requirements are the same as Mac OS 8’s: a 68040- or PowerPC-based machine with at least 12 MB of physical RAM. The disk space required by the update varies, depending on the Mac OS 8 components that are already installed. However, it’s a good bet that you’ll need at least 40 MB of space to update a disk with Mac OS 8 already installed; luckily, the update may need some of that space only during installation.

If you use a clock-chip accelerator on a NuBus Power Mac, you may need to remove the accelerator to install or update to Mac OS 8.1. Alternatively, you can try software utilities that pose an accelerated Mac as a different model; my experience with them has been decidedly mixed. If you try to update a PowerPC-based Mac with 16 MB RAM or less, you may have to restart without extensions (press Shift during startup) to install the update.

Installing Mac OS 8.1 Update — Apple is distributing the Mac OS 8.1 Update as a self-mounting disk image, so there’s no need to use a disk image program. (If you download the segmented version, you need not join the parts, but they must all be in the same folder.) Just double-click the disk image (or the first archive segment) to mount the image on your desktop. From there, it’s theoretically just a question of running the installer.

As with any update to system software, back up your current system and data before updating. In addition, it’s a good idea to make a bootable Disk Tools floppy disk with Mac OS 8.1 before you update. If you have a PowerPC-based machine, use the Disk Tools PPC disk image, available at the same location as the Mac OS 8.1 Update on Apple’s FTP sites. (You need Disk Copy 6.1 or ShrinkWrap 3.0 to make a floppy disk from this image.) For a 68040-based Mac, you must use the Disk Tools 1 disk image, which is apparently available only from the Mac OS 8.1 retail CD-ROM.

After installing Mac OS 8.1, some third-party utilities may report that Open Transport 1.3 libraries (plus the AppleTalk and TCP/IP control panels) are "damaged" because they contain 11 extra bytes. Apple has acknowledged the problem, but the files should function normally. There’s no need to use ResEdit or a utility program to fix the files.

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Incompatibilities — Although software compatibility with Mac OS 8.1 is generally good, I’m listing a few updates and known problems. Also, for a comprehensive list, check the long Mac OS 8.1 special report by MacInTouch, MacFixIt, and MRP.


  • As reported in TidBITS-411, Conflict Catcher 4.1 is required for use with Mac OS 8.1. The update from 4.0 is free.


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  • Although some components of Speed Doubler 8 appear to work with Mac OS 8.1, Connectix says Speed Doubler 8.1 is required and an update will be available soon.


  • StuffIt SpaceSaver 4.5 will prevent machines running Mac OS 8.1 from starting up. Users can disable the StuffIt SpaceSaver control panel; Aladdin says an update is forthcoming.

  • Asante NetDoubler reports a disk error when performing a drag & drop file transfer. Asante has posted an interim release that disables acceleration in this particular case; look for an update to NetDoubler in February.


  • St. Clair Software’s Default Folder, a popular shareware replacement for Super Boomerang under Mac OS 8, has been updated to version 2.8 to provide Mac OS 8.1 compatibility.


In the End — Some people are disappointed by the lack of overt new features, such as a more configurable Finder appearance. However, third-party utilities are filling the gap, including Quadratic Software’s CoolViews (which allows serious customization of Mac OS 8 Finder windows), and the popular desktop makeover utility Kaleidoscope.



If you have large disks with large numbers of files, the new Macintosh Extended Format might be welcome, but I don’t currently recommend switching to Macintosh Extended Format unless you are comfortable with the issues surrounding it (see next article). Otherwise, if you already use Mac OS 8, I think the update is worthwhile, particularly if you don’t use software that needs to be updated for it. Apple isn’t charging for the update, and the bug fixes and additional components will likely be worth the trouble of installing the new version.

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