struct _FAST_IO_WRITE_UNION {
union {
struct { USHORT number_of_packets, write_in_progress_flag; } split;
ULONG join;
} union_;
};number_of_packets
Number of packets currently hold in the shared memory
write_in_progress_flag
Flag indicating if there is a write operation into the shared memory is in progress.
Available starting version 3.2.20. Fast I/O is supported for Windows Vista and later. WOW64 mode is not supported.