(PHP 4 >= 4.3.3, PHP 5, PECL bz2:1.0)
bzflush — Force a write of all buffered data
Forces a write of all buffered bzip2 data for the file pointer bz .
The file pointer. It must be valid and must point to a file successfully opened by bzopen().
如果成功则返回 TRUE，失败则返回 FALSE。