public function write($input)
    {
        if (null === $input) {
            return;
        }
        if ($this->isClosed()) {
            throw new RuntimeException(sprintf('%s is closed', static::class));
        }
        $this->input[] = ProcessUtils::validateInput(__METHOD__, $input);
    }
public function write($input)
    {
        if (null === $input) {
            return;
        }
        if ($this->isClosed()) {
            throw new RuntimeException(sprintf('%s is closed', static::class));
        }
        $this->input[] = ProcessUtils::validateInput(__METHOD__, $input);
    }
public function write ( $ input ) { if ( null === $ input ) { return ; } if ( $ this -> isClosed ( ) ) { throw new RuntimeException ( sprintf ( '%s is closed' , static :: class ) ) ; } $ this -> input [ ] = ProcessUtils :: validateInput ( __METHOD__ , $ input ) ; }
Appends an input to the write buffer.

@param resource|string|int|float|bool|\Traversable|null $input The input to append as scalar,
stream resource or \Traversable
Appends an input to the write buffer .