Tracking down a stolen laptop

This is a bit off-topic, but worthwhile sharing.

I recently, rather unfortunately had my laptop stolen and now I have a replacement; I remember hearing about software that could use the built in iSight to take photos of the thieves and mail them back to me.

After looking on the net and finding some rather good, but pay-ware applications, I came across the Prey Project offering an open source free alternative. I went about installing the software and after checking that it worked went about tweaking it to work with how I have my laptop set up.

I use file vault (thank God it was switched on the laptop that was stolen) and have a password on wake so my personal files are secure. However, even with crontab running Prey once a minute, I figured that if the thief couldn’t log into my laptop, it was a bit pointless. So I have used two tactics that will hopefully result in my getting some pictures if the unfortunate were to happen again:

  1. Enable logging in of the Guest account. This means if the thief reboots the laptop (to try and log in as a different user rather than get the password screen from wake), they can log into a sandboxed account with Prey happily snapshotting away.
  2. Put Prey in the crontab that runs for the login screens:

in /private/etc/crontab (this may not exist):

*/1 * * * * cd /usr/share/prey; ./

Of course, there are no guarantees, but it’s better than nothing.

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./java: No such file or directory (on Linux)

… and when you look, it exists, it has the correct permissions and everything. Do a long-listing and it’s readable and executable by everyone, and all the directories up the tree also are.  It just doesn’t start!  I spent a while looking for this and didn’t find it on google so hopefully this helps someone.

The clues:

$ file java
java: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.5, dynamically linked (uses shared libs), stripped

$ uname -a

reports a 64-bit OS.

The problem is you’re running a 64-bit OS with insufficient 32-bit shared library support to run a 32-bit binary.

The solution:

$ sudo aptitude install ia32-libs

(Courtesy of

PS: Yes, I know I could get a 64-bit java interpreter….