Returns the block size for the file or its storage device. The block size is a constraint for clients of the Stream Manager: All reads, writes and position changes need to be a multiple of that size.
戻り値:
The block size for a specific file or storage device.
意見:
Some files might be opened with flags that require I/O transfers to be a multiple of this size. The stream manager will query this function to resolve calls to IAk(Auto)Stream::GetBlockSize( ).
Also, AkFileDesc::uSector specifies a number of sectors in multiples of this value.
Files/IO devices that do not require byte alignment should return 1.
Whether file opening was deferred or not, GetBlockSize() is always called right after the first call to Open(), in the client's thread, and is never called again.
警告:
Returning 0 is not allowed and will likely make the Stream Manager crash.