My PyQt GUI book Create Simple GUI Applications has been updated, with new chapters on Qt Designer and multithreading. Get it here.

Control memcached from the command line

memcached is a general-purpose distributed memory caching system originally developed by Danga Interactive for LiveJournal but now used by many other sites. It is often used to speed up dynamic database-driven websites by caching data and objects in RAM to reduce the number of times an external data source (such as a database or API) must be read. Here we describe the options available from the command line to control a memcached instance via unix socket or IP:port.

Kill unresponsive applications on Linux

Sometimes things go a bit wrong. Sometimes they go very wrong. XKill is a simple little application that allows you to kill a running X application that has got out of kilter. Think of this as a quick way to get back control of your Desktop.

Change the 'Desktop' directory on Linux

On desktop setups where icons are shown on the desktop these are normally taken from the specific folder ~/Desktop. If you find you want to show icons from either your Home or another directory for a particular install/user you can do so by editing the user-dirs config file as described here.

Collaborate in the shell with screen (multiuser)

Screen is a neat little program that allows you to use multiple virtual terminals in a single session on Unix/Linux and Mac. However, it does more than just that. It can also allow you to share your current session on a machine with another user - allowing you to collaboratively hack away at a problem in real time.

Bash Command Substitution

Bash command substitution performs a given command replacing the marker with the resulting standard output. It is particularly useful when you want to store the output of a command in a variable or as an alternative method of chaining multiple commands together.

Control Console with SysReq

System request (often abbreviated SysRq or Sys Req) is a key on keyboards for PCs that has no standard use. This key can be traced back to the operator interrupt key of the IBM System/370 mainframe computer. But under Linux there's a bunch of useful things available via this key.

Install Cinnamon on Ubuntu 12.04

Cinnamon is a re-implementation of the Gnome 2 desktop in GTK3 developed by the Linux Mint project as an alternative to both Gnome3/Shell and Ubuntu Unity. Here we explain how to install Cinnamon on top of your Ubuntu installation, without installing Linux Mint.

Use screen to manage persistent sessions

GNU Screen is a command-line application that allows use of multiple virtual sessions within a single real terminal or remote session. Importantly, it allows for persistent running of command-line applications independent of the shell that initiated them program, meaning active applications can persist during disconnection.

KDE fileprotocol+transportprotocol://

While getting started using the new SVN I was looking for a quick way to download the contents of an SVN to local disk. This can be useful when doing research on methods employed by other plugins or for getting a local development copy where SVN access is unavailable. Under KDE you can normally access any remote location using the standard URL format. For example, an SVN (using the svn://) protocol would normally be accessed using the URL style svn://

Apache vs. the Slashdot Effect

Increasing traffic is the measure of success for a website. More visitors equals more exposure which in turns generates more income. However, if you have hosted your site on a low-end package you could get hit by excess use charges just as your start celebrating your success.