public function getGroupName()
    {
        $userId = $this->getGroup();
        if ($userId) {
            $userData = posix_getgrgid($userId);
            return ((isset($userData['name'])) ? $userData['name'] : null);
        }
        return false;
    }
public function getGroupName()
    {
        $userId = $this->getGroup();
        if ($userId) {
            $userData = posix_getgrgid($userId);
            return ((isset($userData['name'])) ? $userData['name'] : null);
        }
        return false;
    }
public function getGroupName ( ) { $ userId = $ this -> getGroup ( ) ; if ( $ userId ) { $ userData = posix_getgrgid ( $ userId ) ; return ( ( isset ( $ userData [ 'name' ] ) ) ? $ userData [ 'name' ] : null ) ; } return false ; }
return user group name of the file or directory

@return      string|bool|null         user group name of file group
return user group name of the file or directory