Amazon.com finally has a Linux downloader for use with their MP3 store (mentioned previously here)! You can get it (for a number of different distributions) here.

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As a corollary to my last post, it’s important to be careful when calculating file seek positions (if you’re skipping around that way). It turns out it’s necessary to cast all of the numbers being used when calculating a seek position to a large integer, such as unsigned long int.
By the way, Rob had some […]

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Any system that encodes values in some set number of places has a limit on the values that can be held. For example, old, mechanical cash registers were physically limited in the number of digits they could ring up. Likewise, modern LCD cash registers are limited by the number of digits available on the screen, […]

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I have written before about the usefulness of command-line scripting in computational science.
Today, while looking for some information on various file test operators in bash (e.g. to check whether a file or directory exists), I found this amazing guide. As the author puts it,

This tutorial assumes no previous knowledge of scripting or programming, but progresses […]

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Occasionally, on our cluster, a node will crash. If a job was running on it that spanned multiple nodes, sometimes the other nodes won’t get the message that their fellow has crashed, and they will just keep running whatever processes are on them.
I call these “Zombie” processes, because they just lumber along eating CPU time […]

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