Bash - Control Flow

Bash Control Flow Code

title: ## Contents 
style: nestedList # TOC style (nestedList|inlineFirstLevel)
minLevel: 1 # Include headings from the specified level
maxLevel: 4 # Include headings up to the specified level
includeLinks: true # Make headings clickable
debugInConsole: false # Print debug info in Obsidian console

Overview

Control flow statements in Bash scripting allow you to control the execution of your script based on conditions and loops. Here are some common control flow statements:

1. If Statement: The if statement is used to test a condition and execute a block of code if the condition is true. If the condition is false, the code block is skipped.

if [ condition ]; then
    # code to execute if condition is true
fi

2. If-Else Statement: The if-else statement is an extension of the if statement that allows you to execute a different block of code if the condition is false.

if [ condition ]; then
    # code to execute if condition is true
else
    # code to execute if condition is false
fi

3. Elif Statement: The elif (else if) statement allows you to test multiple conditions and execute a different block of code for each condition.

if [ condition1 ]; then
    # code to execute if condition1 is true
elif [ condition2 ]; then
    # code to execute if condition2 is true
else
    # code to execute if both conditions are false
fi

4. For Loop: The for loop is used to repeat a block of code a certain number of times.

for variable in list; do
    # code to execute for each item in the list
done

5. While Loop: The while loop is used to repeat a block of code as long as a condition is true.

while [ condition ]; do
    # code to execute while condition is true
done

6. Case Statement: The case statement is used to match a variable against several patterns and execute a different block of code for each match.

case variable in
pattern1)
    # code to execute if variable matches pattern1
    ;;
pattern2)
    # code to execute if variable matches pattern2
    ;;
esac

Remember, the conditions in these control flow statements are tested using test constructs like [ condition ] or [[ condition ]]. The double bracket [[ ]] construct is a more modern version that supports more complex conditions and regular expressions.

See Also

• Bash - Check if Directory Exists

• Bash Code Snippets

• Linux, Ubuntu, Kali Linux

• Zsh

• Development Map of Content

• Windows Sub-System for Linux (WSL)

---

Appendix

Note created on 2024-05-17 and last modified on 2024-05-17.

See Also

Backlinks

LIST FROM [[Bash - Control Flow]] AND -"CHANGELOG" AND -"04-RESOURCES/Code/Bash/Bash - Control Flow"

---

(c) No Clocks, LLC | 2024