Utility software

Mac 911 - June 2006

Terminating locked files

I can’t delete several files I downloaded, because they are locked. How do I delete locked files?—James Van de Velde

I’ll assume we’re talking about files that OS X thinks are locked but that aren’t really—they are just being stubborn. (To unlock truly locked files, just select them, press Command-I, and, in the Info window, disable the Locked option.) This is the most frequently clicked-on question in the Macworld Mac OS X Forum FAQ (created by Derik DeLong and the late great Grant Grubb ). Because the question is so popular—and comes my way at least a couple of times a month—I’ll offer the answer one more time.

Launch Terminal and type

sudo rm -R
, making sure there’s a space following the
rm
command and another space following
-R
. Drag the locked file into the Terminal window; this adds the file’s path name to the command line. Press the return key and, if prompted to do so, enter your administrator password and press return again. In a moment or two, the file will be vaporized. Repeat for other files that you can’t trash by other means.

Really, Truly Deleted When you need to get rid of locked files, use Terminal’s rm command.

Here’s what’s going on:

sudo
gives you temporary superuser powers—powers that can be used for good or evil, so be very careful to type the command correctly. The
rm
command is Unix-speak for “remove directory.” The
-R
switch specifies inclusion of the target item’s entire file hierarchy (meaning that the command will delete the item and all its contents). If you added an
-i
switch (as in
-iR
), Terminal would ask you if you’d like to examine the contents of the item and then would ask for permission to delete each specific element within (each file within a folder, for example). When you don’t specify that
-i
switch, as soon as you press return, your locked item will disappear, never to come back again—so make sure that you select the correct file.

Gently down the stream

I’d like to add some streams to the Radio section of iTunes. I have some favorite stations that I want to tune into, and would like to access them through iTunes. Can you give me the steps for adding streams?—Matt Ernst

Indeed I can.

Step 1 Let go of the idea that you can add streams to the list that appears when you select Radio in iTunes’ Source list. Apple controls that section, and you can’t add to or subtract from it.

Step 2 Understand that you can add your own streams to the iTunes library.

Step 3 To do this, go to Shoutcast ( www.shout cast.com ), find a station you wish to stream to your computer, and click on the Tune In button next to that station.

Gathering Streams Once you’ve added audio streams to iTunes, you can collect them all in one smart playlist.

Step 4 You’ll be presented with the option to download a .pls (playlist) file. Download it. If your browser asks which application you’d like to use to play it (iTunes will be the default) and you click on OK, the .pls file will be automatically added to iTunes and the station will start streaming. If it doesn’t, double-click on the downloaded file to add it to iTunes, and the station will begin playing.

Step 5 You needn’t rely on outfits like Shoutcast and Live365 ( www.live365.com ) for your iTunes streams. Some terrestrial and Internet radio stations offer .pls links from their home pages. You can also add a station manually if you have its streaming address. With such an address in hand, choose Advanced: Open Stream In iTunes and enter it in the URL field.

Step 6 Once your stations are in the iTunes library, you may wish to create new playlists for them. You can, for example, group all the streams you have by creating a smart playlist, using the condition Kind Contains Audio Stream. Although you can’t add items to Apple’s Radio list, you can copy stations from that list to a stream playlist— just drag them from the Radio list to the playlist.

Snapz and the colossal cursor

Arrowing Adventure Want to see a big cursor in your screenshots? Select a Snapz Pro capture style with your keyboard instead of the mouse.

I was impressed by your recent Mac 911 blog item describing how to increase the size of the cursor in versions of Mac OS X prior to 10.4 (macworld.com/1184). I want to use the big cursor with Ambrosia’s Snapz Pro X to make better screen shots and screen movies for training materials. Alas, Snapz Pro won’t accept input from a more-expansive cursor. Is there a way around this?—Frank Lowney

No matter how you supersize your cursor—whether you do so with the help of a third-party utility or, in Tiger, with the Cursor Size slider found in the Mouse tab of the Universal Access preference pane—Snapz Pro won’t normally show it. But there is a way to get that giant cursor in your screenshots. Once you invoke Snapz Pro, choose your favored style of screen grab using the keyboard’s number keys. Pressing

1
will do a full-screen capture,
2
will capture just an on-screen object,
3
will grab a selection, and
4
will record a movie. Once you’ve invoked a capture style, the large cursor will be able to select whatever you want to capture (see “Arrowing Adventure”).

Imperfect pitch

While working on an iMovie project, I extracted the audio from a movie clip and copied it to GarageBand so I could use some of GarageBand’s effects on it. The audio plays normally in iMovie, but it’s slower and deeper in GarageBand. I’ve tried changing the tempo in GarageBand, but that doesn’t speed up the audio track. What’s going on?—Terry Southern

That audio clip you extracted is formatted as a 48kHz AIFF file, which plays back normally in iMovie. When you import it into GarageBand, its sample rate converts to 44.1kHz. Changing an audio file’s sample rate may also change its length and pitch unless the converter compensates for it. GarageBand doesn’t compensate, and that’s why your file sounds deeper.

Thankfully, iTunes does compensate for sample rate conversion—playing a converted file at its proper length and pitch. So the secret is to first import the audio clip into iTunes and convert it using the Advanced: Convert Selection To command; then bring the converted file into GarageBand, where it will play back normally.

By default iTunes will convert the selection to AAC, but you can change the file format to something else—AIFF, WAV, MP3, or Apple Lossless—in iTunes’ preferences (iTunes: Preferences: Advanced: Importing).

If you want to keep the file as an AIFF but convert it to 44.1kHz, you must manually choose its sample rate, as iTunes will keep the sample rate at 48kHz unless you instruct it to do otherwise. To choose the sample rate, while in the Importing area of the Advanced preference, choose AIFF Encoder from the Import Using pop-up menu, Custom from the Setting pop-up menu, and 44.1kHz from the Sample Rate pop-up menu that appears in the AIFF Encoder window.

Tip of the month

Faster Macworld URL access: Macworld often provides references to Web pages or products in the form of addresses such as

macworld.com/xxxx,
where xxxx is a four-digit code. Typing that into Safari’s Address field can be tiring, especially if you follow those URLs a lot; if you’ve entered similar URLs in the past, Safari automatically offers a list of similar links to choose from, none of which is the one you want.

I came up with a bookmarklet to make the process easier. Enter the following code in Safari’s Address field:

javascript:nbr=prompt('Enter%20the%20URL%20of%20the%20Macworld%20reference%20you%20want%20to%20visit:','0638');window.location.href='http://www.macworld.com/'%20+%20nbr;

All that text has to run together, without any spaces.

You’ll be asked for a four-digit number. Enter the number you found in Macworld and click on OK in the dialog box. To make the bookmarklet more accessible, just drag it to the Bookmarks bar. —Steve Hammond

[ Senior Editor Christopher Breen is the author of The iPod and iTunes Pocket Guide (Peachpit Press, 2005). ]

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