Arithmetic
When we want to perform arithmetic (math) in Bash, we need a little managing for it to work. As always, there are different ways to perform it. Above all, there are two different ways of performing so-called arithmetic expansion. Double brackets (( ))
or with the built-in command let. There are also logical operators that help us with condition management.
In many other languages it is straightforward. We only write what we want to add or subtract or whatever it may be:
#!/usr/bin/env bash
#
# An example script for the linux course
value1=5
value2=10
value3=$value1+$value2
echo "$value3" # Prints 5+10
In Bash, however, it is not quite as we thought, as we can see above. Move ahead and we’ll take a look at what it might look like.