Working with Linux as system administrator, there likely will be times that need to lock the user. It can be useful when limiting access to a system temporary. This tutorial...

SHA-256 is a cryptographic hash function that can be used for verifying file integrity. For example, to check that the file has not been altered during transfer over the network...

In Linux, file permissions can presented in human readable form (e.g. drwxr-xr-x) and in octal format (e.g. 755). This tutorial shows how to get file permissions in octal format in...

Linux is a multi-user operating system that allows multiple users to connect to the system at the same time and access system resources. Sometimes we may need to find currently...

In Linux, there are various commands to work with text files processing. Sometimes we may need to count number of occurrences of a word in a file in Linux. This...

Pulse width modulation (PWM) is a technique that allows to control analog devices with a digital signal. Raspberry Pi Pico has GPIO pins that can be configured as PWM signal...

SHA-1 is a cryptographic hash function that can be used to verify file integrity. For example, to check that the file has not been modified during transfer over the network...

MD5 is a cryptographic hash function that can be used for verifying file integrity. For example, to check that the file has not been modified during transfer over the network...

Base64 is an encoding and decoding scheme that often used to convert binary data to an printable ASCII text format, and vice versa. This tutorial shows how to perform Base64...

In Linux, there are commands that allows to perform various operations on files. Sometimes we may need to remove last N lines from file in Linux. This tutorial demonstrates how...