04. Command Line Interface

You will learn

what a terminal is: from the classic teletypes to the virtual terminals and the terminal emulators
what a shell is and how it runs a command
what environment variables are, how to define them (export) and how the shell uses PATH to find commands
how the shell reads a command line: words, escaping with \, single and double quotes, variables and redirects
what signals are and how to handle them with trap
how to run processes in the foreground and in the background (&, jobs, fg, bg)
how the shell expands file names with globbing (*, ?, [...], {...})