Common Commands

Essential bash commands and built-ins for scripting and automation

Powerful Looping Strategies: Iterating Files and Lists in Bash Scripts

Powerful Looping Strategies: Iterating Files and Lists in Bash Scripts

Master essential Bash looping techniques using `for` and `while` to automate repetitive system tasks efficiently. This comprehensive guide covers iterating over lists, processing numeric sequences, and robustly handling files line by line using best practices like `while IFS= read -r`. Learn the foundational syntax, advanced loop control (`break`, `continue`), and essential techniques for powerful, reliable shell scripting and automation, complete with practical code examples.

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Understanding Exit Codes: Effective Error Handling with $? and exit

Understanding Exit Codes: Effective Error Handling with $? and exit

Master Bash error handling by understanding exit codes (0 for success, non-zero for failure). This essential guide details how to use the special variable `$?` to inspect the status of the last command and leverage the `exit` command for intentional script termination. Learn best practices using `set -e` and conditional logic (`&&`, `||`) to build robust, self-diagnosing automation scripts.

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Securely Accepting User Input: Essential Techniques for the Bash read Command

Securely Accepting User Input: Essential Techniques for the Bash read Command

Learn to securely and efficiently accept user input in Bash scripts using the `read` command. This guide covers essential techniques for prompting, handling passwords silently with `-s`, setting timeouts with `-t`, and performing basic input validation and sanitation to create more robust and secure interactive scripts.

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Bash Conditionals Compared: When to Use test, [ , and [[

Bash Conditionals Compared: When to Use test, [ , and [[

Unlock the nuances of Bash conditional statements with this comprehensive guide comparing `test`, `[ ]`, and `[[ ]]`. Learn their distinct behaviors, from POSIX compliance and variable quoting requirements to advanced features like globbing and regex matching. Understand their security implications and choose the right construct for robust, efficient, and portable shell scripts. This article provides clear explanations, practical examples, and best practices to master conditional logic in Bash.

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Mastering Positional Parameters: A Guide to Bash Script Arguments

Mastering Positional Parameters: A Guide to Bash Script Arguments

Unlock the power of dynamic Bash scripts by mastering positional parameters. This comprehensive guide explains how to access command-line arguments using `$1`, `$2`, and special variables like `$#` (argument count) and the crucial `"$@"` (all arguments). Learn essential best practices for input validation, understand the difference between `\$*` and `\$@`, and see practical examples for writing robust, error-checked scripts that adapt flawlessly to user input.

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