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Hack to Fix GNOME Shell Stylesheet Problems

At the present time the GNOME Shell is badly broken (See GNOME Bugzilla 650971 and 642876) with respect to its handling of GNOME Shell extension stylesheets. The issue was mainly exposed by the user-theme extension developed by John Stowers of gnome-tweak-tool fame. The history of how this problem arose and why it still exists is interesting. In January 2011, before there was wide experience of extensions in the GNOME Shell, a leading GNOME Shell developer decided to create a GNOME Shell extensions repository and a GNOME Shell Extensions webpage. The user-theme extension was added to this repository in mid-March 2011

GNOME Shell Weather Extension

The current version of the GNOME shell does not come with a built-in weather application. As a result I, and at least two other developers that I am aware of, have written GNOME Shell extensions to provide this functionality. In this post, I show you how to write a simple weather extension for the GNOME Shell using the free weather data from World Weather Online (WWO). What is different about this particular weather extension is that it displays 5 days’ worth of forecast data and uses the weather data suppliers’ images instead of GNOME icons to display a pictorial representation

Shell Fork Bombs

Fork Bombs have been around in shells since the first Unix shell was written. Examples of Unix/Linux fork bombs include: :(){ :|: & };: $0 & $0 & The first example is often used by system administrators to test user processes limitations. Once a successful fork bomb has been activated on a system it may not be possible to resume normal operations on the system without rebooting, as the only solution to a fork bomb is to destroy all instances of it. Probably the best way to prevent a user invoking a fatal fork bomb on Linux is to add

Remove Color Code Escape Sequences

Here is a simple way using sed to remove special characters such as color codes and other escape sequences from each line in a log file or the output from a utility like screen. $ sed -r “s/x1B[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g” If you wish to see the actual escape sequences, one way is to use the -r or -R options to the less utility -r or –raw-control-chars Causes “raw” control characters to be displayed. The default is to display control characters using the caret notation; for example, a control-A (octal 001) is displayed as “^A”. Warning: when the -r option is used, less

More GNOME Shell Customization

If you plan to customize the GNOME Shell in any meaningful way, you need to understand the technologies underlying the GNOME Shell and understand how to write a GNOME Shell extension to provide the customization that you require. In this post I delve deeper into the technologies behind the new GNOME Shell and provide sample code for a number of simple extensions which demonstrate how to customize and extend various components of the GNOME Shell user interface. Essentially, the GNOME Shell is an integrated window manager, compositor, and application launcher. It acts as a composting window manager for the desktop