Shell - The Command-Line Interpreter

Ubuntu Tutorials - Herong's Tutorial Examples

∟Shell - The Command-Line Interpreter

This chapter provides introductions and tutorial examples on Ubuntu shells, which are command-line interpreters and scripting languages. '/bin/bash' is the default shell for interactive sessions. '/bin/dash' is the default shell for shell scripts.

What Is Shell

What Is Bash (Bourne Again SHell)

Create and Run Bash Script

Bash Command Line Interpretation Steps

Bash Shell Session Customization

Command Input/Output Redirection

Shell Session Command History

"tmux" - Terminal Multiplexer

Takeaways:

/bin/bash, Bourne Again SHell (Bash), is the default shell on Ubuntu computers for interactive sessions.
/bin/dash, The Debian Almquist SHell (Dash), is the default shell on Ubuntu computers for shell scripts.
"type -a command" looks up the command in 4 sources: alias, user-defined function, built-in command, and program file.
~/.bashrc contains commands to be executed when a non-login and interactive Bash session starts.
"history" displays past commands used in the current and previous shell sessions.
~/.bash_history carries past commands from the previous session to the next session.
"<" in command line redirects input channel to a file instead of the keyboard.
">" or ">>" in command line redirects output channel to a file in replace or append mode.
"2>" or "2>>" in command line redirects error channel to a file in replace or append mode.
"&>" or "&>>" in command line redirects both output and error channels to a file in replace or append mode.
"|" or "|&" in command line pipes output channel or output+error channels to the next command as input.
"tmux" tool can be used to manage multiple shells in a single terminal window.
"tmux" tool automatically keeps its shells running when the terminal is disconnected.

Table of Contents

About This Book

Introduction to Ubuntu Systems

GNOME - Desktop Interface and Environment

►Shell - The Command-Line Interpreter

Process Management

Memory Management

Files and Directories

APT (Advanced Package Tool)

Network Connection on Ubuntu

Internet Networking Tools

SSH Protocol and ssh/scp Commands

Administrative Tasks

References

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