How to split a wallpaper for multiple monitors on GNU/Linux

So I wanted to split a 3840×1080 wallpaper in two halves for my dual monitor based KDE 4.10.5 setup. Obviously there are several applications that would do the job, but why bother when ImageMagick can do it with a one-liner. The “magick” is achieved by using a geometry argument:

What is the latest Skype for Business User-Agent string?

When using a client other than Skype for Business (formerly known as Lync) to connect with your Office 365 account, you’ll need to provide the Microsoft Lync servers with a user-agent string they recognize as an “acceptable” client. The reasoning behind this is surely to give you the best possible experience and not at all to lock out other messaging clients.

BlueOnyx 5107R - make_sock: could not bind to address 0.0.0.0:80

Recently, I became aware that Apache’s access and error_log on a BlueOnyx 5107R server were both zero byte files. Restarting Apache to correct the issue resulted in the following error message: (98) Address already in use: make_sock: could not bind to address 0.0.0.0:80 no listening sockets available, shutting down Unable to open logs Fixing the issue was a simple matter of issuing the following commands: killall -9 httpd service httpd start It seems that during logrotate, Apache was not able to get new file handles to write to the new log files.

Arch Linux - Failed to start Verify integrity of password and group files

The shadow.service unit reported that it had failed and threw the following error message: “user ‘colord’: directory ‘/var/lib/colord’ does not exist”. I had no recollection of housing such a user, but by issuing the command below there was hard proof (image to the right) that colord was indeed a homeless user on my system, and her home was supposed to have been /var/lib/colord.

How to reverse a shortened URL with a single command on GNU/Linux

Remember that old saying: if you don’t know the source, don’t click it? With all these new URL shortening services, that advice seems to have been thrown out the window. As a result, evildoers are embracing the technology to disguise their malware sites behind shortened URLs. This is obviously effective as an URL like hxxps://goo.gl/3BSi65 would have a much easier time getting past your spamfilter than say something like hxxp://h4x0r.tld/inject.aspx

Slackware ARM on the Raspberry Pi 2- 38 days later

Excited by the prospect of hosting my blog on the new Raspberry Pi 2, I decided lately to wave goodbye to the local datacenter and unleash a Slackware Linux box into the wild (full story here). Everything went (mostly) without a hitch until I wanted to get back in sync with the Slackware-current tree. After applying the available updates and issuing a reboot, the system seemed operational and nothing from the logs gave any indication of imminent failure.