Unix Programs

Create a CPU Frequency and Temperature Monitoring Bash Script for Linux-based Systems

4 minutes to read

This post will show you a way to monitor CPU frequency and temperature on Linux-based systems without aid of any programs or packages that are not commonly preinstalled on major GNU/Linux distributions. No extra hardware drivers are required: the magic is done merely by a short Bash script in just a few lines that only relies on mechanisms provided by the Linux kernel itself and some most essential Unix commands. …

Perform Manual dnf history undo

8 minutes to read

My choices of GNU/Linux distributions are Fedora for desktop computers and CentOS for servers. Both of them feature DNF - Red Hat’s package manager front-end for RPM, which is the primary reason I use these distributions. Although one might argue that it is slow, DNF is very clear on not only what it will do for an action but also what it has done: it maintains a history of package installation and removal operations, which are called “transactions”. …

Use grep as a Substitute for cat

4 minutes to read

I came across a fascinating and educative article, Unix Recovery Legend, when someone posted a link to it on Reddit. The article presents a story of the writer, Mario Wolczko, and some other colleagues attempting to recover a system partially destructed by rm -rf /. The rm command was interrupted before it scraped off directories like /usr, but it was too late to save /bin, /dev and /etc, which were respectively the directory for basic executable programs, device files, and system configuration files. …