Taming the beast

• Article 2 of 53
• iCreate, April 2004
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There used to be two common sights in a Mac user’s life. The first was a desktop, filled with lots of icons, such as hard drives, CDs, applications and the trash; the second was also an icon: a little computer icon, just like that very first Mac, but with a smiley face for a screen. The reason this second icon was so familiar was because it was the first thing that appeared when you switched on your Mac. Or, more importantly, when you restarted it.

Restarting used to be “popular” with Mac users. Every time an application crashed or froze, it was time to restart the computer. Every time you added a printer, scanner, external drive or even a mouse to the system, restart time was just round the corner. Installed a program that did something even slightly exciting? Restart time.

And it wasn’t as if application crashes were rare either. Even sneezing or sitting down too hard near your Mac used to make even the simplest of programs crash so hard that nothing short of a lot of swearing and a swift flick of the power switch/mallet three times a day would keep that puppy running smoothly.

Apple knew that couldn’t go on and spent a lot of the 90s trying to retrofit the Macintosh operating system – the software that controls a computer and its hardware, lets programs run, and gives them their familiar appearances – with the bells and whistles necessary to make crashes a thing of the past. Eventually, they decided they couldn’t do it, and bought an operating system that could: NextStep, based on Unix. After a few more years of retrofitting (this time, to make NextStep work more like the old Mac OS), Mac OS X was born and there was a sudden outbreak of stability.

Relative stability that is. There are still problems to be found, some easy to come across, others well hidden. Trouble is, even by the best estimates, around 5% of any computer program has bugs. That means that, charitably, Mac OS X probably has 50,000 bugs or so, waiting to be found. Some already have been, but at any moment, you could be the next lucky Mac user to discover a problem.

Fortunately, there are easy ways to combat these problems and even prevent them – if you read on, anyway.

Most things people stumble over are not usually that hard to solve. They’re often just an inability on the part of computer programmers to realise that what they thought was really, really obvious isn’t so obvious to the rest of us. Who, for instance, though that moving a CD to the Trash was the best way to eject a CD?

But what of that stuck disk that refuses to eject? There’s no eject button on most Mac CD drives, unlike on PCs, so there’s no “hard eject” mechanism to force it to come out. That’s an actual problem. So how to fix it? The most common reason a CD won’t come out when you press the eject button on a keyboard is that it is still in use. You won’t find that out until you try the drag-to-the-trash method of ejecting, however: naughty Apple hasn’t put an error message in for when that method goes wrong, yet. But even so, what does “in use” mean? It could mean that iTunes is playing it. But it could also mean that there’s an application running off it, meaning you’ll have to quit the guilty application – or quit all your applications if you don’t know which one it is. At the absolute worst, you might have to restart your Mac, keeping the mouse button held down at start-up to force open the CD drive.

This, though, is easy stuff. Once you’ve reached a certain level of skill with OS X, it’s only the “odd things” and the things that are genuinely wrong that will give you any real bother. “Odd things” are different from person to person. To a Unix user, all the underlying ideas are easy in OS X; it’s finding what you want in the maze of graphics that are the problems. To a Windows user, it’s not having a Start button, or trying to open an application using the “Return” key. To a user of the old Mac OS operating system, it’s pressing the Apple key and N only to find that you get a new window instead of a new folder in OS X. But almost everyone tends to get confused by one particular new feature of OS X: permissions.

Back when the Mac was born, the idea that it would be anything except one individual’s personal computer was a far-off idea. Multi-user computers exposed to the world via the Internet were the realms of the US military and research labs, running high-end operating systems such as Unix. Even more so, the idea that a Mac user would have anything less than total control over his or her computer and be told what to do by it was anathema to Apple. So the Mac let its user do just about anything he or she wanted to, short of deleting the entire operating system.

The Unix world is not so trusting. Every single file and folder on a Unix computer has a list of things that users can do it, depending upon who they are and what “groups” they belong to: the file’s owner might be able to read it and edit it; the computer’s group of admin staff might be able to read the file but not edit the contents of the file; everyone else might be able to see that the file’s there but not doing anything with it.

Unfortunately, it’s not always obvious to the average Mac user what permissions a file or folder has. So unsuspectingly, you might drop a folder into the Trash, then try to empty it, only to discover that you don’t have the permissions to delete one of the files in the folder. Panther, fortunately, has made it easier to discover and remedy this problem than earlier versions of OS X: it will at least warn you that you’re about to drag a locked file into the trash unlike 10.0 say, which apart from providing no warning, would force you to take the file out the trash, unlock it (assuming you had the right permissions), put it back in and then empty the trash. Now, you can open the Trash, highlight files or folders while they’re still in there, and select Get Info from the Finder’s Edit menu to discover what your permissions are and then alter them.

You won’t be able to do this or run any troubleshooting software, however, unless you have an administrator account (you can tell from your User Account Systems Preference whether you have a “standard” or “admin” account). If you aren’t an administrator, there’s a whole lot of things you won’t be able to do in OS X, and almost nothing you can do to fix it if it goes wrong in any substantial way. If you are intent on fixing your own Mac, make sure you have an administrator account to hand even if you don’t log in using it, otherwise you won’t be able to affect any files except your own ones – particularly not any system files.

At the moment, I’m assuming you’re got a computer in some kind of working order. But what if yours just sits there quietly, doing nothing, when you try to start it up? Now it could be a hardware problem at this stage: a lightning strike has nuked your hard drive, for instance. But we’re hoping otherwise. Check your power leads aren’t loose; unplug all your peripherals (with the exception of your keyboard and mouse); see if moving the power plug to a different socket helps; if you’ve added an Airport card, additional memory, or PCI card, try taking them out again (remembering to de-static yourself first); if you’re using a laptop and you’re not running off the mains, plug in the power adaptor and remove the battery – a flat battery can sometimes confuse your laptop into believing it has no power even when the power adaptor is plugged in; if you happen to have a spare power lead or battery, try using it instead of your regular one, in case there’s something wrong with it. If none of that works, your luck’s probably out and it’s time to get the hardware specialists in.

But there’s still more that can go wrong between pushing the power button and getting to your desktop. As soon as you press that button and power reaches your Mac’s circuitry, it looks to something called Open Firmware to tell it what to do next. This is a chip containing a slew of settings about devices, such as your Mac’s memory, and which device to boot off. Sometimes, poor old Open Firmware gets a bit confused and you need to reset its data so it can start from the beginning and let you boot up. To get to the Open Firmware prompt, you’ll need to hold down four keys at start-up: Apple, Alt, O, and F (for Open Firmeware). Then you’ll be presented with a nasty grey screen and an arrow prompt. Just type these commands in and you’ll be fine though: reset-nvram (hit enter); set-defaults (hit enter); reset-all (hit enter). The machine should reboot, and if you’ve found the correct source of your problem, all should be well.

There’s another set of settings, including the date and time, stored in yet another chip called the PRAM. Just as Open Firmware can get confused, so can PRAM. Flush it with another ambidextrous set of key strokes at start-up (Apple, Alt, P and R) if you’re having some trouble getting past the boot panel that has all those “Starting Network Services” type messages.

In rare situations, you might not make it that far. You get the Apple logo and then nothing. This is usually a symptom of a corrupt “kernel”. Think of the kernel as the foundations of the operating system: on it is built everything that makes the computer do anything more than show you a grey screen. If the kernel is corrupt (or missing. I’ve seen people boot their computers into OS 9 then move their System, Applications and Library folders, together with all the files beginning “mach”, into a folder marked “OS X stuff” to make it neater for them when they’re using OS 9), you’re screwed, although a brave soul can try to copy across a clean one from another copy of OS X.

More likely, however, something that communicates with the kernel directly is to blame – a common symptom of this is the “kernel panic” screen, which tells you something is wrong with your computer and needs to be restarted (the OS X 10.0–10.1 kernel panic message was nasty white text on black background dumped on your screen with no clues as to what was happening). Usually, that’s a peripheral that’s gone wrong or a badly written piece of software for connecting a peripheral to the computer that’s known as a driver. Unplugging all your peripherals is a good way to test for possible causes of a repeating kernel panic, but usually, they are infrequent and unpredictable things. Running the Apple Hardware Test CD that came with your computer can also help find hardware problems: boot off it like an OS X installer CD and then run the tests to see what might be wrong.

The hardware test CD is also useful for the opposite problem: the peripheral or printer that has no effect whatsoever on the Mac. If you can’t print, the System Profiler in your utilities folder and the hardware test CD can both tell you if your Mac is receiving signals from your invisible printer or not. If it can’t, you may have a dodgy lead or you may have too many peripherals connected to an unpowered USB hub, overloading it and forcing it to turn off all its attached devices. If the signals are getting through, you may need to fire up a copy of Printer Setup Repair (see walkthrough) to repair your printing system. Or you may not have the right drivers installed for your printer (a common problem for devices such as printers and scanners; it’s far less likely for digital cameras, hard drives, portable USB drives, external CD drives and other forms of storage); fortunately, you can usually download the correct drivers from the manufacturer’s web site.

If you do get as far as the boot panel – but no further – make a note of which service stopped the Mac in its track; if it’s something that relies on having a network, for example, you’ll know there’s probably something up with your network settings. Holding down the Shift key at start up can help you get passed these boot-up problems: it puts the computer into Safe Mode (another one of those ideas Apple has started to borrow from Microsoft) which loads a minimal system and allows you to get into the Mac’s graphics-based interface to change settings, if possible. If it’s not, it’s time to learn some more sets of start-up key strokes (somehow, holding down F8 at start up to get all these choices seems preferable): V; and Apple and S. The former puts you in verbose mode: bye, bye eye candy; hello, nasty white on black text. It may not be pretty, but you’ll get all the messages of distress your computer may have been putting out until this point and maybe a clue as to what’s causing the problem. The second set of key strokes puts the computer into Single User mode: you are given only a command line and nothing else. Together, assuming you have the Unix experience necessary, you may be able to hold out against that looming OS X reinstall you’ve been fearing.

Typically, verbose mode will reveal that something can’t be accessed on the network or that permissions are wrong for some directories. The latter can be fixed with Disk Utility (see walkthrough). But the former is usually a sign of damaged network preferences. Use Safe Mode to get into your computer then make arbitrary changes to the network settings, save them, then change them back. Also, turning off network interfaces you don’t use (such as Ethernet, Airport or Internal Modem) is a good help in situations where your boot panel freezes, since your Mac may be waiting for a response from these unavailable networks. Equally importantly, make sure you have them listed in the right order in the Network section of the Systems Preferences; although OS X is supposed to run through them in order as it tries to access different networks, it is possible, depending on your settings, for it to decide to stop at a certain interface and go no further. An Airport connection, whose base station tries to connect to AOL for Internet access, is perfectly valid as a network configuration, so OS X will look no further down its list of connections than Airport. Which is fine, as long as you’re only trying to network with other Airport users within range. But since AOL UK doesn’t support Airport base stations with its software, no Internet connection can be made. So even if your internal modem is properly set up for Internet access, you’ll never be able to network with other computers using Airport and obtain an Internet connection as well unless you swap their order in the network interfaces list.

Corrupt preferences can kill both programs and operating system alike, depending upon whose preferences they are. Safe Mode will help you overcome the corrupt preferences of a log-in item, since it stops all log-in items from running, but obviously it won’t fix anything particular to an application you start up once you’ve made it through to your desktop.

Other enemies of application stability are third-party programs that modify OS X’s behaviour; particularly well known culprits are things like Default Folder, extra menu-bar items, or any of Unsanity’s “haxies” such as WindowShade that use its Application Program Enhancer (APE). If you are experiencing odd crashes or slow performance, locating the APE preference pane (in any of the PreferencePane folders in the various Library folders of your hard drive), dragging it to the Trash and then logging out and back in can often bring merciful relief.

Even worse than the application that crashes is the application that won’t go away. Force quit (available from the Apple Menu or by pressing Apple+Alt+esc) allows you to terminate with extreme prejudice any badly behaving application. Sometimes even that isn’t enough, and you’ll have to use the Activity Monitor’s Quit function to kill off a program that refuses to die.

That covers most of the possible problems with OS X itself. Like a pensioner in a retirement home, however, OS 9 waits ready for the slightest bit of attention you might give it. Run some old program and up it pops ready to do its best to help you in case you’ll visit it again.

In comparison to OS X, OS 9 is a dream to fix. No keystrokes to memorise for Classic since the Advanced tab of the Classic System Preferences provides its own Safe Mode (“Turn off Extensions”) and permissions fixer (“Rebuild Classic Desktop”). If these simple tools aren’t enough, a glance in a couple of folders is usually enough to fix most problems. Unlike OS X with the cryptic naming system and hidden folders and files inherited from Unix, OS 9 wears its files on its sleeves: problem with QuickTime? Just drag all the files marked QuickTime out the Extensions folder in your System Folder, download the latest installer and then reinstall it. Your corrupt files are a thing of the past. Similarly, there’s only one folder that will contain all the computer’s preferences rather than numerous ones inflicted on us by OS X (/etc, /var/db, /Library/Preferences and ~/Preferences, to name just a few). That’s not to say every OS 9 problem is easy to fix: damaged fonts can be the root causes of many problems that are seemingly unrelated and you’ll need a third-party utility such as Font Doctor to identify and repair a damaged font.

OS 9 and OS X are similar to analogue and digital TV. OS 9 can be flaky and temperamental and as more bugs appear, offer progressively poorer performance; but usually, all you have to do is fiddle with the aerial and it’s fine, albeit it not brilliant. OS X, however, is crystal perfect until enough bad things have accumulated that the whole picture just goes completely.

So it pays to ensure you maintain your system regularly: back up your data; run Disk Utility regularly, particularly after you’ve installed new software, to repair both permissions and the disk itself; run Software Update regularly to ensure you have the latest (and hopefully the most bug-free) versions of your system software; be careful not to install software from unknown third-parties that puts files in awkward places or modifies the system too severely (be especially wary of anything that needs an administrator password for no really good reason); and a surge protector is a must if you live in a part of the country that gets stormy weather often.

Take good care of OS X and it will take good care of you.

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