ftruncate

<?php             $stream = fopen('php://temp/maxmemory:0', 'r+');



            fwrite($stream, 'x');

            ftruncate($stream, 0);

        }



        return $stream;

<?php         $input = fopen('php://temp/maxmemory:0', 'r+');



        fwrite($input, 'x');

        ftruncate($input, 0);



        $this->loop->addReadStream($input, $this->expectCallableExactly(2));