src/cache/File.php
public function get($id, $default = NULL) {

        $filename = $this->cache_file($id);

        if (@filemtime($filename) > time()) {
            $fp = @fopen($filename, 'r');
            if ($fp !== false) {
                @flock($fp, LOCK_SH);
                $value = unserialize(@stream_get_contents($fp));
                @flock($fp, LOCK_UN);
                @fclose($fp);
                return $value;
            }
        }

        return $default;
    }
public function get($id, $default = NULL) {

        $filename = $this->cache_file($id);

        if (@filemtime($filename) > time()) {
            $fp = @fopen($filename, 'r');
            if ($fp !== false) {
                @flock($fp, LOCK_SH);
                $value = unserialize(@stream_get_contents($fp));
                @flock($fp, LOCK_UN);
                @fclose($fp);
                return $value;
            }
        }

        return $default;
    }
Retrieve a cached value entry by id.

@param   string $id id of cache to entry
@param   string $default default value to return if cache miss
@return  mixed
@throws  CacheException