`SECONDS` is like `PWD`: the shell keeps track of updating it somewhere, and it'll tell you how long your shell has been running. https://www.oreilly.com/libra

`SECONDS` is like `PWD`: the shell keeps track of updating it somewhere, and it'll tell you how long your shell has been running. https://www.oreilly.com/library/view/shell-scripting-expert/9781118166321/c03-anchor-3.xhtml https://www.oreilly.com/library/view/shell-scripting-expert/...