This is a wordpress plugin that uses the phrets library to connect to an MLS association's listings database using the RETS protocol and perform searches. It stores config data in the wp_options table (saved as "rets-config"), such as server url and login info. This plugin is meant to be mostly used in theme files, for example:
$search = trim(@$_GET['search']);
$props = apply_filters('rets-search', array(), $search); // perform a search against the mls server
foreach($props as $prop) {
// $prop will have several fields implemented by the MLS server, like # of beds/baths, sq.ft. of home, etc.
$mlsid = trim(@$prop->MLSNumber);
echo $mlsid;
}