Multiplication on command line terminal

bash, command-line, unix

Solution

Yes, you can use bash's built-in Arithmetic Expansion `$(( ))` to do some simple maths

$ echo "$((5 * 5))"
25

Check the Shell Arithmetic section in the Bash Reference Manual for a complete list of operators.

For sake of completeness, as other pointed out, if you need arbitrary precision, `bc` or `dc` would be better.

Problem

I'm using a serial terminal to provide input into our lab experiment. I found that using ``` $ echo "5X5" ``` just returns a string of `"5X5"`. Is there a command to execute a multiplication operation?

Original source