Regular Expression Syntax
There are two types of regular expressions: regex (OS_Regex) and sregex (OS_Match).
Regex (OS_Regex) syntax
This is a fast and simple library for regular expressions in C.
This library is designed to be simple while still supporting the most common regular expressions.
Sregex (OS_Match) syntax
This is faster than OS_Regex, but only supports simple string matching and the following special characters.