Description:

This is a dynamic shared object (DSO) for PHP that will add Perl Compatible
Regular Expression support.

The syntax for patterns used in these functions closely resembles Perl. The
expression should be enclosed in the delimiters, a forward slash (/), for
example. Any character can be used for delimiter as long as it's not
alphanumeric or backslash (\). If the delimiter character has to be used in
the expression itself, it needs to be escaped by backslash. Since PHP 4.0.4,
you can also use Perl-style (), {}, [], and <> matching delimiters.