I was exploring Text.Regex.Posix and found that I was not able to do a non-greedy match by modifying the quantifier with a "?". How can I achieve non-greedy match in Text.Regex.Posix?

If it's Posix, it is greedy. Successive submatches are as long as possible subject to the constraint that a longest possible overall match be found if such exists. Doug McIlroy