peteg's blog 2006-01-12-Xorg.autumn

Doing battle with Adobe Reader.

This application is just plain broken. It wants to be an operating system: from the look of Version 8 Adobe has tried to shoehorn most of the Mac OS X desktop into their proprietary web-browser-of-sorts. Hmm... perhaps this is what the Windows people have been dealing with all these years. unnecessary, unwanted feature-creep and integration.

The updater is broken. Just download the latest version. Oh wait, you need to get the "Download Manager" to download it for you. Grrr. And you sure do a lot of waiting on all these bloody programs... and then it tries to do the update thing anyway! Screw it, too much trouble.

Now, down to business: the instant-gratification eBook I rashly bought yesterday only lets me print 20 pages of it per month, which seems to me to be a strange compromise between the real world (fair use?) and what's possible with electronic authoritarianism. I found this mechanism is indeed easy to defeat.

A moment's reflection tells you that it is common (UNIX) courtesy for an application to only fiddle with stuff in your home directory, which you (of course) have free access to. (It could do nasty things if it's SUID or using OS DRM services, and that's surely in the post.) The hope is that by swapping some files we can reset the print counter, and that is indeed the case. On Mac OS X, simply, if inconveniently:

Kill Adobe Reader. I assume you haven't used any of your print quota.
Copy your ~/Library/Acrobat User Data somewhere safe. It seems to be a bit sensitive to a few things, so I suggest:
```
cd ~/Library
tar cfv ~/AUD.tar Acrobat\ User\ Data/
```
Fire up Adobe reader, print as much as you're allowed to.

Kill Adobe Reader, save the new state and extract the old:

cd ~/Library
mv Acrobat\ User\ Data/ /tmp/AUD.old
tar xfv ~/AUD.tar

Go back to step 3.

If things screw up you can move your saved state back into place and things should work as they did before. The standard disclaimer applies to all of this: it worked for me, I hope it works for you, don't sue me if it doesn't.

I see I'm not the first to think of this.

iPod Shuffle Gripes

OK, I've owned the damn thing for about a month, time to put the boot in. :-) What I like:

Unplugging the headphones makes it pause. Perhaps all iPods do this, but my iRiver didn't.
The control is much better designed than my old iRiver.

What I'd like:

Some audible warning that it's out of juice. The little all-purpose LED glows red, I think, and that's that.
A way to delete songs on the player itself, so I can fill it up with random crap and on-the-spot nuke the annoying stuff, rather than having to tediously go through it afterwards in iTunes at home.

What I don't like:

The dinky dock. My old iRiver had a standard mini-USB port, which happened to be the same as my Canon PowerShot A75. One cable was all I needed. Moreover I have no way to recharge it without having the iBook plugged in and running — there's no juice on the USB bus when it's suspended.

Ars Technica killed theirs by running a car over it. This program may yet liberate me from iTunes inanity.

Powering the iBook from the car.

I trudged all over Sydney CBD today looking for a new pair of Docs and something that would let me recharge the iBook from the car. It seems the old Docs shop on Pitt St Mall has folded, and the joint down George St that for years proudly advertised cut-price Docs has gone for the factory- (China-) direct brand instead. I'd forgotten what a hassle it is shopping on the street.

Anyway, to cut a long ramble short, I ended up buying a "Powertech Plus Cat. MP-3463 3.5 Amp Universal Step-up DC/DC Converter for Notebook Computer" from Jaycar on York St for <$40 />. The sealed-in cardboard says it was made in China and is distributed by Electus Distribution, and I can guarantee you that the cardboard was printed there too. I can't find it in either of their catalogues. There is also a 6 Amp version for those who have something hefty.

It works, with one small wrinkle: the iBook-sized plug adaptor is wired backwards! Fortunately the iBook is up to that game, simply ignoring a reverse-polarity 24 volts. The solution is to wedge the plug adaptor onto the cable backwards. For the curious these Italians have the details, or you can try to figure out what Apple is on about.

André pointed out Terminator to me, a cross-platform terminal emulator written in Java. It sounds promising; the only things tying me to X.org are XEmacs, a DVI viewer and xterm.

Easing into the 21st Century.

Met up with André in Newtown for a coffee and some lunch, and being the unpaid ambassador for Apple that he is, we ended up in the Apple store on Broadway and I parted with <$119 /> for an iPod Shuffle, a replacement for my venerable 256Mb iRiver iFP-390T I bought in Boston at the end of 2003. I can't see why it needs an on/off switch.

Backups at CSE.

I was very proud of myself when I cooked up the following to backup and encrypt my email to CSE's shiny new selfbackup server in a streaming manner. Assuming you've set up GPG and your environment sets and appropriately, this will encrypt a tar archive of ~/Library/Mail using your public key:

tar c ~/Library/Mail/ |
   gpg -e -r  |
   ssh selfstore.cse.unsw.edu.au "cat - > /backups//.mail.gpg &&
      mv /backups//.mail.gpg /backups//mail.gpg"

Decryption is just a matter of gpg -d | tar x.

Wow, a computer-controlled back hoe.

I tried building one of the pneumatic pumps in CSSoh catalogue but was sorely disappointed by the lack of pressure I got out of it. It's possible that my Nickel-Metal-Hydride rechargeables do not provide enough voltage to make the motor run quickly enough. There's plenty of torque, just not enough air pressure...

My big haul (in a little box) of Lego™ bits turned up. I bought them from the Brick Artist Depot, run by a very pleasant and accommodating bloke in Atlanta. Very happy. Go and make him a rich man.

I now own another two motors that look identical to those that come with the Lego™ Mindstorms kit. Slightly worrying is that these are known to fail. Conversely the four turntables should come in quite handy.

Allen Smith recently released an updated version of Bricksmith. It's an excellent Lego™ CAD tool for Mac OS X.

This looks interesting: a Wikipedia-style collaborative robotics textbook. Sounds like a great idea.

A three speed automatic transmission built out of Lego™. Wow.

Isn't darcs great?

I've put off trying out darcs for ages, indeed, longer than I've been putting off checking my stuff into a crusty old CVS repository. My main operations are diffing (to see if I've screwed things up more than I'm aware of) and finding that little bit of code from ten revisions back that hacked around that little problem that came back. pcl-cvs in XEmacs was good for the former, and I just dug around in the repository itself for the latter.

It seems there's a pcl-cvs-equivalent for darcs in the pipeline, and moreover is being actively hacked. Find the repo here, darcs'ed, of course.

Well, it works, and that's a good start. A Haskell program doing useful things? Unheard of!

I've been meaning to get a new X-server for a long time now, as the one I have is bug ridden. I thought I'd managed to upgrade it in the past, as the build process for these X.org servers continues after fatal errors... and restarting with make World kicks off a big clean, which makes this behaviour both misleading and somewhat useless to non-hardcore hackers.

The short story is that at this point in time X.org R6.9.0 does not readily compile on Mac OS X 10.4 (using GCC 4.0), but R6.8.2 does after you do some fiddling. Most of the trick is to replace the files that fail to compile with their updated selves in a R6.9.0 tree, and the rest is a small tweak to darwinKeyboard.c. Here's a patch that does it for you. Apply it with:

patch -p1 < patch-Xorg-R6.8.2-OSX-10.4.3-GCC-4.0.1

in your <build-dir>/xc/ directory.

Thanks to Torrey Lyons for the pointers.

Lego™ pneumatics: what else could be said? The extensive survey of compressors is great.

Lego™ intends to release a new version of Lego™ Mindstorms in the third quarter of 2006 — here's the press release, and Slashdot has some links.