Linux / X-Windows: Which process owns this window?

Once in a while, there’s a piece of junk on the desktop, and the question is who should be blamed for it. The short answer is: $ xwininfo and fetch the window’s ID from the line at the beginning saying e.g. xwininfo: Window id: 0x860000a “xclock” And next, fetch the alleged process ID: $ xprop [...]

Linux: Permanent graphics mode (resolution) on Cinnamon

The goal Quite simple: Set a fixed graphics mode on the computer screen. More precisely, make Cinnamon (version 3.2.6) on Linux Mint 18.1 (Serena) show the desktop with a predefined resolution, no matter what happens. Spoiler: I failed. But I got close enough for practical purposes, and collected a lot of knowledge while trying. So [...]

Making a snapstot of a full Ubuntu / Mint repository on the local disk

What’s that good for? This isn’t about maintaining a local repository that mirrors its original, following along with its changes. The idea is to avoid the upgrades of a lot of packages every time I want to install a new one with apt. Maybe I should mention that I don’t allow automatic upgrades on my [...]

apt / dpkg: Ignore error in post-install script

You have been warned This post shows how to cripple the installation of a Debian package, and make the system think it went through OK. This might very well bring your system’s behavior towards the exotic, unless you know perfectly what you’re doing. In some few cases, like the one shown below, it might actually [...]

Linux: Command-line utilities for obtaining information

There are many ways to ask a Linux machine how it’s doing. I’ve collected a few of them, mostly for my own reference. I guess I’ll add more items as I run across new ones. General Info inxi -Fxxxz (neat output, but makes the system send me security “password required” alert mails because of attempts [...]

Linux: Atheros QCA6174′s Bluetooth disappearing after reboot

When Bluetooth goes poof Having rebooted my computer after a few months of continuous operation, I suddenly failed to use my Bluetooth headphones. It took some time to figure out that the problem wasn’t with the Cinnamon 3.8.9 fancy stuff, nor the DBus interface, which produced error messages. There was simply no Bluetooth device in [...]

VIA VL805 USB 3.0 PCIe adapter: Forget about Linux

TL;DR Bought an Orico PCIe adapter for USB 3.0 for testing a USB device I’m developing (PVU3-5O2I). It has the VL805 chipset (1106/3483) which isn’t xHCI compliant. So it works only with the vendor’s own drivers for Windows, which you’ll have to struggle a bit to install. Attempt with Linux That the device is detected [...]

ImageMagick convert to scale jpgs

Instead of using my scanner, I put my cell phone on some kind of stand, and shot a lot of paper documents (voice activation is a blessing). But then the files are unnecessarily large. Don’t need all that resolution. So $ for i in * ; do convert “$i” -scale ’33%’ -quality 75 “smaller/scan_$i” ; [...]

Linux: Writing a Windows MBR instead of grub

On a test computer, I use /dev/sda1 to contain whatever operating system I need for the moment. At some point, I installed Linux Mint 19.1 properly on that partition, and then I wanted to return to Windows 10. After writing the Windows 10 image to /dev/sda1, I got a message from grub saying it didn’t [...]

systemd / DBus debugging starter pack

Introduction Trying to solve a 90 second wait-on-some-start-job on each boot situation, I found that there’s little info on how to tackle a problem like this out there. Most web pages usually go “I did this, hurray it worked!”, but where do you start solving a problem like this if none of the do-this-do-that advice [...]