src/Http/Stream.php
public function write($string)
    {
        if (! $this->isWritable()) {
            $message = 'Stream is not writable';

            throw new \RuntimeException($message);
        }

        $this->size = null;

        return fwrite($this->stream, $string);
    }
public function write($string)
    {
        if (! $this->isWritable()) {
            $message = 'Stream is not writable';

            throw new \RuntimeException($message);
        }

        $this->size = null;

        return fwrite($this->stream, $string);
    }
Write data to the stream.

@param  string $string
@return integer

@throws \RuntimeException