Answers for "or in regex"

regex any character

/(.*)/

or in regex

-> You can use "|" operator in between two differebt regex expression 
in php for selection of any one of them

-> Example for Php only
  [a-z]|[0-9] patteren will select either small alphabet or numbers from 
  a string

regex or operator

Grouping Operators (( ... ) or \( ... \))

find with regex

$ find . -regex "<expr>"  
## Need to match the whole path