Do you still type the long “sudo apt update && sudo apt upgrade -y” commands each time you want to update your Debian-based system? Or are you still navigating into directories (ex: “/var/www/html“) using the cd command each time you have to modify something there?
In Linux, whenever you want to execute any executable program or script, you need to jump into the directory and execute your program or script. But when you execute system commands like ls, pwd, echo, apt, and nano, you don’t need to jump into any
The source is a built-in command-line tool that reads and executes the commands from the specified file (in order) as its argument in the current shell. Each command from the specified file will be delivered to the TCL interpreter to be read and run, making
The env command is an advanced version of printenv with a few more features to tweak your environment variables, like setting new environment variables, printing all environment variables, or executing a command or script in a modified environment. I would also suggest you read the
The printenv command is an alternative to the env command used to fetch the value of a specified variable name (key) used as an argument. If no variable name is assigned to printenv, it will print all environment variables in your system. Tutorial Details Description
The bash or any other shell uses multiple profiles, also known as shell configuration files, like “/etc/profile“, “~/.bash_profile“, “~/.profile“, “~/.bash_login“, “~/.bashrc“, “~/.bash_history“, and “~/.bash_logout” to configure the user’s interactive login or non-login shell. Files Description /etc/profile It stores the variables, aliases, functions, etc. that are
The environment variables are a set of key-value pairs that define the shell environment and can affect the behavior of the ongoing programs that are executed in the current shell session. The programs running in the current shell session can access the variable values from
The whatis command is used to fetch a one-line description of the specified command from the manual pages. The search query (command) you will use as an argument to get the description will be looked up in the index database maintained by the “maindb” program.
The which command locates the executable command or file location in the user’s environmental path. It will give you the complete path of executable command or file pointing towards in your file system. Tutorial Details Description Which Difficulty Level Low Root or Sudo Privileges No
The usermod command is a user management tool to modify user account information like username, user ID, default shell, home directory, and many more. Tutorial Details Description Usermod (Modify User Information) Difficulty Level Moderate Root or Sudo Privileges Yes OS Compatibility Ubuntu, Manjaro, Fedora, etc.
Linux administrators are allowed to create “normal user accounts” with a range from 1000 to 60000 uids, where uid 0 is reserved for “root users” and “system users” are allowed uids from 1 to 999. Normal users might rarely reach this threshold, creating so many
The chown command is used to modify the user and group ownership of files and directories. It will be helpful to restrict the access permissions for files and directories to selective users and members of group. Tutorial Details Description Chown (Change Ownership) Difficulty Level Moderate
