Anybody who has used command-line systems for a serious amount of time will love grep. But today I stumbled across ack, which (for many things) is better than grep and a whole lot nicer to use.

The best bit? It’s pure Perl, therefore also uses real Perl regular expressions. Yes, there might be grep --perl-regexp, but nobody bothers compiling that in. Plus ack has some other neat features.

See more at the ack website.

My first bunch of boards arrived back from BatchPCB and I’m really impressed.  Great printing for the silkscreen and a really professional looking product.  One of the boards I ordered was a breakout board for the SMD PIC 18F2321, the first surface mount board I have tried.
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During a recent conversation with another Dave he pointed me at the Facebook group “No, you’re not a photographer, you just own a camera” (update May 2011: this no longer exists).  Whilst I don’t agree with most of the comments on there (they are generally rude and unhelpful) it does raise an interesting point: How high the bar should be set for whether you are really a photographer or not?
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It is sometimes useful to limit the running time of a process, either to stop it from using up all resources or to make sure nightly cron jobs don’t continue into working hours.

I needed this for rsync, to let a remote backup server slowly catch up if large amounts of data were added to the live server during the day. A useful post on the rsync mailing list discusses an rsync patch but also the timeout command.

After installing (the Debian package is simply timeout) it is as easy as running with the number of seconds to run for:

It is also possible to specify the signal which will be sent to a program, which is useful if you do not want to simply send SIGKILL. I used SIGHUP in the hope that rsync would have a chance to exit gracefully:

A full list of signals and their numeric values can be found in man 1 kill.

A wrapper script is also available from Johannes Buchner.