src/Database/Attach/Media.php
public function getLastModified($fileName = null)
    {
        if (!$fileName)
            $fileName = $this->disk_name;

        return $this->getStorageDisk()->lastModified($this->getStoragePath().$fileName);
    }
public function getLastModified($fileName = null)
    {
        if (!$fileName)
            $fileName = $this->disk_name;

        return $this->getStorageDisk()->lastModified($this->getStoragePath().$fileName);
    }
Returns the last modification date as a UNIX timestamp.
@return int