Basic Bash Regex
Basic regex operator is =~ with basic syntax
1[[ "string" =~ pattern ]]
NOTE pattern is not quoted, only the string.
Very basic example when checking if a variable has either values 'running' or 'exited':
1status='running' ## change to 'exited' and '' to see it works
2if [[ "$status" =~ running|exited ]]; then
3 echo "Is either running or exited"
4else
5 echo "Nope, I don't understand that status"
6fi