private function getPipe()
    {
        if (!isset($this->pipe) || !isset($this->proc)) {
            $desc = [['pipe', 'r'], $this->stream, \fopen('php://stderr', 'w')];
            $this->proc = \proc_open($this->cmd, $desc, $pipes);

            if (!\is_resource($this->proc)) {
                throw new \RuntimeException('Error opening output stream');
            }

            $this->pipe = $pipes[0];
        }

        return $this->pipe;
    }
private function getPipe()
    {
        if (!isset($this->pipe) || !isset($this->proc)) {
            $desc = [['pipe', 'r'], $this->stream, \fopen('php://stderr', 'w')];
            $this->proc = \proc_open($this->cmd, $desc, $pipes);

            if (!\is_resource($this->proc)) {
                throw new \RuntimeException('Error opening output stream');
            }

            $this->pipe = $pipes[0];
        }

        return $this->pipe;
    }
private function getPipe ( ) { if ( ! isset ( $ this -> pipe ) || ! isset ( $ this -> proc ) ) { $ desc = [ [ 'pipe' , 'r' ] , $ this -> stream , \ fopen ( 'php://stderr' , 'w' ) ] ; $ this -> proc = \ proc_open ( $ this -> cmd , $ desc , $ pipes ) ; if ( ! \ is_resource ( $ this -> proc ) ) { throw new \ RuntimeException ( 'Error opening output stream' ) ; } $ this -> pipe = $ pipes [ 0 ] ; } return $ this -> pipe ; }
Get a pipe for paging output.

If no active pager process exists, fork one and return its input pipe.
Get a pipe for paging output .