Tag Archives: shell

A Quick Introduction to sed(1)

Posted on July 29, 2017 by

The sed(1) stream editor is one of the most powerful tools from the classic Unix tool box. It is a close cousin to the ed(1) command line editor and a descendant of the ex(1) editor, the command line mode of … Continue reading →

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Maven: Discovering Dependency Conflicts

Posted on August 30, 2014 by

Among other things, Maven’s dependency plugin displays the result of Maven’s dependency resolution mechanism. The output of the dependency:tree goal makes it easy to see where transitive dependencies come from. This week I discovered that recent versions of the plugin … Continue reading →

Posted in java | Tagged , , | 2 Comments

Quick Tip #6: Triggering Actions on File Close

Posted on December 30, 2013 by

Sometimes it’s useful to trigger an action after a file is closed. Suppose you started a lengthy download on your notebook and you want to suspend it as soon as the download is done. There are several ways to achieve … Continue reading →

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Quick Tip #5: Navigating in Source Trees

Posted on April 14, 2013 by

I often move around in checked out Subversion or Git source trees on a Bash command line. Directory structures tend to get quite deep (especially in Java projects), so one problem keeps coming up frequently: Changing back to the base … Continue reading →

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Bourne Shell Parameter Expansion

Posted on January 20, 2013 by

Classic Bourne Shell has a handy feature that many people don’t seem to know: Parameter Expansion. Stephen Bourne describes it in An Introduction to the UNIX Shell, which is part of the original Unix V7 manuals from 1978. Among other … Continue reading →

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Scripts That Just Don’t Work

Posted on July 22, 2012 by

Sometimes people ask for my help when their shell scripts don’t work. I’ve seen all kinds of problems, ranging from trivial to really, really weird. The one I’m describing in this article is definitely from the weird category, but I’ve … Continue reading →

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Quick Tip #4: Sorting Large Files

Posted on May 23, 2010 by

With traditional Unix sort(1), the size of the files you can sort is limited by the amount of available main memory. As soon as the file gets larger and your system has to swap, performance degrades significantly. Even GNU sort … Continue reading →

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