Getting a Glimpse of the Boot Process

A lot goes on behind the scenes whenever you restart your Macintosh; verbose booting provides a unique glimpse of the Unix underpinnings of Mac OS X.

A lot goes on behind the scenes whenever you restart your Macintosh. In pre-OS X days, we couldn’t really tap into this knowledge; at most, we knew what control panels and extensions had been started, but that was about it. Nicely, OS X gives us a few ways we can turn on verbose booting, providing more esoteric knowledge for our coffers.

Being able to see exactly what goes on when you start your computer is easier than you may think. Longtime OS 9 users may recall the Shift or spacebar keyboard tricks: hold one down during bootup and you’ll disable, or interactively choose, your extensions, respectively. The same principle lies behind verbose booting in OS X: simply hold down the

Getting a Glimpse of the Boot Process

and V keys.

When you do this during startup, your screen should turn black and you’ll see tiny text instead of the normal happy Mac or Apple logo. Most of this text may not make much sense to you, but some messages about your hardware will appear as OS X tries to figure out what you’ve got plugged in or installed.

You may find that the text scrolls by too fast for your inquisitive mind to handle. No worries, though; since OS X is based on Unix, nearly everything gets written down. Once you’re logged into the Finder, ...

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