Filename
There are two methods for obtaining the filename. The first is uri(), which return the uri metadata. The second is filename(), which returns the file's basename, or a custom filename entry from the stream's metadata.
$stream = FileStream::open('houses.txt', 'rb');
echo $stream->uri(); // /home/my_user/files/houses.txt
echo $stream->filename(); // houses.txt
If you specify a custom filename metadata, then it will be favoured instead of the basename.
$stream = FileStream::open('houses.txt', 'rb');
$stream->meta()->set('filename', 'my_file.txt');
echo $stream->uri(); // /home/my_user/files/houses.txt
echo $stream->filename(); // my_file.txt