Bash If...Else

Using If...Else Statements in Bash

This section explains how to use conditional statements in Bash scripting.

If Statements

If statements allow you to execute code based on a condition. If the condition is true, the code block will run.

The condition is enclosed in square brackets[ ] and the statement ends withfi, which isif spelled backward, marking the end of the if block.

# Basic if statementnum=15if [ $num -gt 10 ]; then  echo "Number is greater than 10"fi

If...Else Statements

If...else statements provide a way to execute one block of code if a condition is true and another block if it is false.

Theelse keyword introduces the alternative block, and the statement ends withfi.

# If...else statementnum=8if [ $num -gt 10 ]; then  echo "Number is greater than 10"else  echo "Number is 10 or less"fi

Elif Statements

Elif statements allow you to check multiple conditions in sequence. If the first condition is false, the next one is checked.

Theelif keyword stands for "else if," and the statement still ends withfi.

# If...elif...else statementnum=10if [ $num -gt 10 ]; then  echo "Number is greater than 10"elif [ $num -eq 10 ]; then  echo "Number is exactly 10"else  echo "Number is less than 10"fi

Nested If Statements

Nested if statements allow you to place an if statement inside another if statement, enabling more complex logic.

Each if block must be closed with its ownfi.

# Nested if statementnum=5if [ $num -gt 0 ]; then  if [ $num -lt 10 ]; then    echo "Number is between 1 and 9"  fifi