Base structure.
Flush the stream.
Return true (1) if this handler performs work like accessing the file system which may block. Used as a hint for determining the thread to access the handler from.
Seek to the specified offset position. |whence| may be any one of SEEK_CUR, SEEK_END or SEEK_SET. Return zero on success and non-zero on failure.
Return the current offset position.
Write raw binary data.
Structure the client can implement to provide a custom stream writer. The functions of this structure may be called on any thread.