Mac Geekery

Since I use Mercurial and it doesn’t have Xcode integration, I find that I’ll have added classes or whatnot and they will not have been added to the repository and I’ll forget about them come checkin time. That’s bad.

So I thought about ways to remedy this, and after describing the issue to myself, the issue was clear. “When I add new files to the directory, it should run hg add on the files.” Well, when when we need to do something when a directory changes, we use launchd yes? Yes.

So I made a launchd item that ran a script any time my specific repository changed. Since this is just for yourself, it can go in ~/Library/LaunchAgents. The item should set the current and working directories to the repository so the context of the hg commands is proper.There's more »

Ever get that lovely “overlapped extent allocation” or “missing extent” error when checking your drive in Disk Utility? Notice how it never gets repaired when you repair the disk? There’s a reason: it’s technically irreparable.

The extents that the error is referring to are the file fragments on your drive. There’s a special catalog file called the extents B-tree (this is also sometimes referred to as the extents or extents overflow file) that holds all of the information on which files have which fragments on the disk. Each fragment is an extent. When you have a missing extent then you have a record that states that there are a certain number of extents for a file, but the known extents are too few for that file.There's more »

CUPS is the name of the service that handles printing in Mac OS X 10.3 to 10.5. It has a lot of features that aren’t really pushed in the GUI in Mac OS X, but users are able to get at those features by using the special administrative interface at http://localhost:631/.

One of those features is classes. A class, in this context, is a group of printers that can be made to look as if it were one printer. This is great in lab settings where you have half a dozen printers of the same type as you can add them all to a class on a print server and have everyone print to that queue. Then whichever printer is free (or round-robin) will print the job.There's more »

I needed to change many iBooks from having a Preferred Network (and wanting to keep looking for that network) to automatically joining any open network and not giving a preference to that certain network.

I found that the two preference files involved were:

• /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist
• /Library/Preferences/SystemConfiguration/preferences.plist

I also found that the computer name is kept in preferences.plist, so copying these two files out to all the iBooks would have resulted in a same-name-game fiasco. Soooo, my solution was to:

1. Copy /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist out to all the iBooks using Apple Remote Desktop.
2. Issue the following UNIX command as root also using Apple Remote Desktop:

This command will search through the preferences.plist file for the word Ranked and replace it with the word Automatic.

I went to the GUI feedback session at WWDC last year and in the midst of all the yelling and screaming over the new dock and menu bar there was one guy with a wholly different mission: be able to turn off tooltips. His complaint (a valid one, I feel) is that every time he wants to sit and think about what’s on-screen, a little yellow box comes up where the mouse is, and there’s no real “safe spot” for the mouse that doesn’t do this in most applications.

So, I present a little tip I discovered shortly afterwards and appear to have not written up. I dedicate this to Tooltip Guy, wherever he is.

defaults write -g NSInitialToolTipDelay 99999

You now have 99.999 seconds to think at a given time. Replace -g with the ID of any application to change it in that application.

So I'm paranoid, but not THAT paranoid.

Sometimes I feel like using "Secure Empty Trash", but that uses '/usr/bin/srm' with the '-m' option (7 passes), which can take a while to complete. Most of the time, I only care about what might turn up with simple file recovery tools in case my drive gets stolen (as opposed to covering my tracks from say law enforcement or a foreign government) so really, a single pass should be plenty for my needs. I could always use 'srm' directly, but the convenience the built-in tool offers in handling the Trashes on various volumes, and having a built-in menu item is nice.

It turns out the 'srm' option used by "Secure Empty Trash" in Tiger is specified in the file:There's more »

/System/Library/PrivateFrameworks/DesktopServicesPriv.framework/Resources/Locum

There is a video on Launchd on Google Video as part of the Google Tech Talks series. The creator of launchd gives a talk on how to use it and how its going to change as of Leopard 10.5. its pretty informative and useful if you are a sysadmin and supposedly if your a programmer also.

As others have noted, there’s nothing all that new about Time Machine other than its UI. UNIX admins have been doing similar incremental backups for ages immemorial. Well, OS X is a UNIX, isn’t it? So it should follow that we can get the same bang-for-buck in Tiger (and possibly prior versions, too). For this, rsync and cpio are our friends today. Adam Knight did most of the footwork here; I just hacked it up into OS X-compatibility.There's more »