String length (${#var}) in Bash Scripting - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does ${#var} do in bash scripting?

It returns the length (number of characters) of the string stored in the variable var.

beginner

How do you find the length of the string stored in variable name?

Use ${#name} to get the number of characters in name.

beginner

What will be the output of this bash code?<br>

text="hello"
echo ${#text}

The output will be 5 because the string "hello" has 5 characters.

beginner

Can ${#var} be used on empty strings? What is the result?

Yes, it can. If the string is empty, ${#var} returns 0.

intermediate

Is ${#var} a command or a parameter expansion in bash?

It is a parameter expansion that returns the length of the string stored in the variable var.

What does ${#var} return in bash?

A Value of the variable var

B First character of var

C Length of the string in variable var

D Number of words in var

${#var} returns the number of characters in the string stored in var.

If var="abcde", what is the output of echo ${#var}?

A 5

B 4

C abcde

D Error

The string "abcde" has 5 characters, so ${#var} outputs 5.

What will echo ${#empty} print if empty=""?

A empty

B 0

C 1

D Error

An empty string has length 0, so ${#empty} returns 0.

Which of these is the correct way to get string length in bash?

A ${#var}

B len(var)

C length(var)

D var.length

In bash, ${#var} is the correct syntax to get the length of a string.

If var="hello world", what does echo ${#var} output?

A Error

B 10

C 2

D 11

The string "hello world" has 11 characters including the space.

Explain how to find the length of a string stored in a variable in bash using ${#var}.

Think about how bash expands variables to get string length.

Describe what happens when you use ${#var} on a variable containing spaces or special characters.

Consider the string as a sequence of characters.