Shell / Bash Roadmap¶

• Roadmap: https://roadmap.sh/shell-bash

1. Introduction¶

• 1.1 What is a Shell
• 1.2 CLI vs GUI
• 1.3 Types of Shells: bash, dash, zsh, fish, ksh, sh
• 1.4 Help Commands (man, help, info, --help)

2. Basic Commands¶

• 2.1 Navigating the Filesystem (cd, ls, pwd)
• 2.2 Files and Directories (mkdir, rmdir, touch, cp, mv, rm)
• 2.3 Viewing Files (cat, less, head, tail)
• 2.4 Finding Things (find, locate, which, whereis)
• 2.5 Searching Content (grep, awk, sed)
• 2.6 Wildcards and Globbing
• 2.7 Echo and Printf

3. Editors¶

• 3.1 vim / nvim
• 3.2 emacs
• 3.3 nano
• 3.4 Basic Editor Ops (create, print, modify)

4. Permissions and Users¶

• 4.1 File Permissions
• 4.2 chmod
• 4.3 chown
• 4.4 chgrp
• 4.5 Users and Groups
• 4.6 sudo and Privilege

5. Bash Scripting Basics¶

• 5.1 Bash Script Anatomy (#!/bin/bash, shebang)
• 5.2 Comments
• 5.3 Variables
• 5.4 Bash Data Types
• 5.5 Environment vs Shell Variables
• 5.6 Bash Aliases
• 5.7 Exit Codes
• 5.8 Direct Execution vs Sourcing

6. Operators and Expressions¶

• 6.1 Bash Operators
• 6.2 Arithmetic Expansion $(( ))
• 6.3 Arithmetic with expr, bc
• 6.4 Command Substitution $(...)
• 6.5 Comparison Operators
• 6.6 File Test Operators
• 6.7 Case Conversion

7. Control Flow¶

• 7.1 Conditionals (if, elif, else)
• 7.2 case Statement
• 7.3 Loops: for, while, until
• 7.4 break and continue
• 7.5 exit

8. Functions¶

• 8.1 Defining Functions
• 8.2 Function Scopes
• 8.3 Parameters and Return Values

9. Arrays¶

• 9.1 Indexed Arrays
• 9.2 Associative Arrays

10. Input / Output Redirection¶

• 10.1 Standard Streams (stdin, stdout, stderr)
• 10.2 Redirection (>, >>, <)
• 10.3 Pipes (|)
• 10.4 Error Redirection (2>, 2>&1)
• 10.5 tee

11. Text Processing Tools¶

• 11.1 grep
• 11.2 awk
• 11.3 sed
• 11.4 cut, paste
• 11.5 sort, uniq
• 11.6 tr
• 11.7 wc
• 11.8 Basic Regex Syntax
• 11.9 Extended Regex

12. Process Management¶

• 12.1 Foreground vs Background (fg, bg)
• 12.2 jobs, disown, nohup
• 12.3 ps, top, htop
• 12.4 Signals and kill
• 12.5 Process Substitution

13. Scheduling¶

• 13.1 cron and crontab
• 13.2 at
• 13.3 systemd timers

14. Networking from Shell¶

• 14.1 curl
• 14.2 wget
• 14.3 ssh
• 14.4 scp, rsync
• 14.5 netstat, ss
• 14.6 ping, traceroute, dig, nslookup

15. System Info and Resources¶

• 15.1 df, du — Disk Usage
• 15.2 free — Memory
• 15.3 uname, uptime
• 15.4 lscpu, lsblk, lsusb

16. Compression and Archiving¶

• 16.1 tar
• 16.2 gzip / gunzip
• 16.3 bzip2, xz
• 16.4 zip / unzip

17. Package Managers¶

• 17.1 apt (Debian/Ubuntu)
• 17.2 dnf / yum (RHEL/Fedora)
• 17.3 brew (macOS)
• 17.4 pacman, apk, etc.

18. Error Handling and Debugging¶

• 18.1 set -e, set -u, set -o pipefail
• 18.2 trap
• 18.3 Error Handling Patterns
• 18.4 Error Logging
• 18.5 bash -n (syntax check)
• 18.6 bash -x and set -x (trace)
• 18.7 Bash Debug Tools

19. Best Practices¶

• 19.1 Quoting (single vs double)
• 19.2 ShellCheck Linting
• 19.3 Style Guide
• 19.4 Idempotent Scripts
• 19.5 Defensive Scripting

20. Advanced Topics¶

• 20.1 Heredocs and Herestrings
• 20.2 Subshells
• 20.3 Coprocesses
• 20.4 Trapping Signals
• 20.5 Read-Only Variables
• 20.6 Bash Built-ins vs External Commands