Siyuan's Blog

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Setting up a KVM virtual machine on CentOS 7

I’ve been running virtual machines for many years. In the past, I mainly used VirtualBox as my hypervisor since it’s free and it can be installed on Linux/macOS/Windows. Recently, I was asked to install a VM on a remote server at work. This time, I decided to set up a KVM-based VM instead. This post describes the steps to set up KVM and create a VM. Terminologies Before we dive into the steps, let me first introduce and explain a few terms.

Night light mode for monitors

Recently I switched from Ubuntu 16.04 to Fedora 28 on my desktop PC. After the installation, I noticed that newer version of GNOME has added a night light feature which is the same as night shift on macOS and iOS and the f.lux software. The feature is great. However, it can only adjust the color temperature of the video output and the monitor’s brightness stays constant. As I work besides a big window, I need higher brightness during the day and lower brightness at night.

Fixing a strange GRUB related filesystem error

I’m running a dual-boot desktop system with Fedora 28 and Windows 10. Today a strange error happened to my GRUB2 installation. This post documents how I fixed the error. Here is what happened: I was installing the Logitech software for my mouse in Windows because I need it to tune a new mousepad. After installation completed, it asked me to reboot the system. I did that and when the system boots up again, the normal GRUB boot menu didn’t appear.

Mixing C and C++ code

C and C++ are two closely related programming languages. Therefore, it may not come as a surprise to you that you can actually mix C and C++ code in a single program. However, this doesn’t come automatically when you write your code the normal way. In this blog post, I will describe what makes it possible to mix the two languages and how to achieve that in code. C and C++ linkage When you compile a source file, the function names are mangled.

Linux shared folder management done right

If you’ve ever collaborated with someone on a Linux machine or worked as a system administrator on a multi-user Linux system, chances are you’ve set up shared folders for groups of people to share data. It’s quite easy on Linux. Well, kind of. I mean, you can simply create a group, add relevant users in, and set the shared folder’s owner and permission correctly. However, this approach has a problem: new files and directories created inside a shared folder doesn’t inherit the owner and permission of the shared folder itself.