Bash Operators

Understanding Bash Operators

This section provides an overview of operators used in Bash scripting, including comparison, string, arithmetic, logical, and file test operators.

Comparison Operators

• -eq: Equal to
• -ne: Not equal to
• -lt: Less than
• -le: Less than or equal to
• -gt: Greater than
• -ge: Greater than or equal to

String Comparison Operators

• =: Equal to
• !=: Not equal to
• <: Less than, in ASCII alphabetical order
• >: Greater than, in ASCII alphabetical order

Arithmetic Operators

• +: Addition
• -: Subtraction
• *: Multiplication
• /: Division
• %: Modulus (remainder of division)
• For exponentiation, use external tools like bc or awk.

Logical Operators

• &&: Logical AND
• ||: Logical OR
• !: Logical NOT

File Test Operators

• -e: Checks if a file exists
• -d: Checks if a directory exists
• -f: Checks if a file is a regular file
• -s: Checks if a file is not empty