How do I bash compare strings to check if a variable matches a specific value?

General Discussions
,
1

I want to bash compare strings by comparing a variable to a given string and execute commands based on whether they match.

What is the proper syntax for string comparison in Bash scripts?

2

When I wanted to bash compare strings, I usually use the [ test command with = inside an if statement, like this:

if [ "$var" = "value" ]; then  
  echo "Match found!"  
fi

Make sure to put quotes around the variables to avoid errors if the variable is empty or contains spaces. It’s simple and works well for exact string matches.

3

For bash compare strings, I often prefer using [[ ]] because it’s more flexible and safer. Here’s how I do it:

if [[ "$var" == "value" ]]; then  
  echo "Strings are equal"  
fi

The double brackets allow more advanced pattern matching too, but for exact match, == works perfectly. Just remember to quote your variables!

4

I was confused at first, but to bash compare strings you can also use the test command:

if test "$var" = "value"; then  
  echo "It's a match!"  
fi

It’s basically the same as using [ ], just more explicit. Whatever style you pick, quoting your variables avoids surprises, especially with empty strings or special characters.