Unix as a Second Language
Looking at user login time with the ac command
The ac command can provide very useful summaries of how much time users spend logged into a Linux system. It gets its data from the wtmp file.
Bash: A primer for more effective use of the Linux bash shell
There are lots of sides to bash and much to know before you're likely to feel comfortable snuggling up to it. This post examines many aspects of this very popular shell and recommends further reading.
Counting individual characters on Linux
If you need to count how many of each character is included in a file or phrase, there are some handy commands you can string together to accomplish this along with scripts and aliases that can make the job easy.
Finding and fixing typos on Linux
The Linux aspell and enchant tools can both ID typos in text files and suggest replacements.
Using Wikipedia from the Linux command line
A tool called wikit provides an easy way to get information from Wikipedia without leaving the Linux command line.
Using functions in bash to selectively run a group of Linux commands
Bash functions can group related commands in Linux and run them as frequently or infrequently as needed. They can also make scripts more readable by organizing commands by the roles they play.
Using bash options to change the behavior of scripts
Here are some of the more popular bash options to control how scripts work on Linux and how to list the available options, including seeing which ones are turned on.
Using 'break' and 'continue' to exit loops in bash
As nice as looping in Linux scripts can be, you might just want to interrupt it sometimes, and the break and continue commands can do this.
Using the Linux apropos command – even if you have to fix it first
The apropos command can help you find commands or discover some you don't yet know, but if you get the response "nothing appropriate", it might need some help.
How to work on Linux with filenames that contain blanks
Filenames that contain blanks can add complexity to the commands you use to work with them. Fortunately, there are several handy ways to make that easier.
How to copy files to multiple locations on Linux
You can run a series of Linux commands to copy multiple files to a folder or copy a single file to multiple folders, but you can save time and trouble by using xargs, loops and scripts.
Checking exit codes in bash
No matter what command you run when using bash, an exit code is returned and the code can tell you if your command was successful or you ran into a problem. Exit codes and error messages are related, but you have to ask to see an exit...
24 ways to check the status of files using if commands on Linux
The Linux if command can help find types, permissions, and content of files, among many other things.
How to find files on Linux and make it easy to find them again
The cd command is easy to use, but adding a couple tricks to your toolbox can make moving around, finding, and remembering the locations of files and directories simpler.
The simplicity and complexity of using quotes on Linux
Using single and double quotes on Linux is easy if you know a few essential rules.
Using the watch command on Linux
The watch command allows you to rerun commands in a loop until you stop it or run into a condition that stops the looping for you. It can be very useful when you're waiting for something to change before you can move on to the next...
Using the yes command to automate responses
The Linux yes command allows you to automate responses to scripts and commands, but how it responds is up to you.
Repeating commands on Linux with or without changes
There are a lot of ways on Linux to make repeating commands easier than retyping them, and here's a nice collection of them.
Rocky Linux 9 arrives with Peridot
New to Rocky Linux 9 is Peridot, a tool that makes it easy for anyone to replicate and extend Rocky Linux.
Using the eval command in Linux to run variables as commands
The eval command allows you to run the contents of variables as commands and can be very useful -- especially in scripts.
