How do you use shell to get the length of a list?

You can use the wc -l command to get the length of a list. For example, to get the number of lines in a file, you can use the following command:

wc -l filename

To find the number of elements in a variable, you can first convert the variable into an array, and then use the wc -l command to get the length of the array. For example:

array=(element1 element2 element3)
echo ${#array[@]}