Beginners Guide to Using “trap” to Catch Signals and Handle Errors in Shell Script
Shell Signal Values A signal is a message that some abnormal event has taken place or a message requesting another…
4 years ago
DevOps
How to Make a Variable read-only (constant) in Bash and Korn Shell
Creating Bourne Shell Constants A variable can be made read-only with the following syntax: readonly var[=value] The square brackets around…
4 years ago
Examples of “shift” Command in Shell Scripts
The shift Statement Sometimes a script does not require a specific number of arguments from users. Users are allowed to…
4 years ago
Korn Shell select Loop
The select statement in the Korn shell creates a menu. This construct is for the Korn shell only. The syntax…
4 years ago
How to use “break” and “continue” statements in shell scripts
The break Statement The break statement allows you to exit the current loop. It is often used in an if…
4 years ago
How to use until loop in Shell Scripts
The until Loop The until loop is very similar to the while loop, except that the until loop executes as…
4 years ago
“while” Loop Examples in Shell Scripts
The while loop allows you to repeatedly execute a group of statements while a command executes successfully. The syntax for…
4 years ago
How to Configure Network Namespaces in Docker Containers
This post tells how Docker uses network namespace to isolate resources. The following figure is the lab setup to help…
5 years ago
“su: Authentication failure” – in Docker
The Problem In some situations, a normal user within a Docker container cannot run 'su' command to switch user. When…
5 years ago
How to Pause and Resume Docker Containers
Question: How to Pause and Resume running containers on docker host? This post will help to know about pausing and…
5 years ago