I am using notepad and analysing the output using Filemon. Suppose there is
a file abc.txt. First time that file is read by first issuing
FastIoQueryStandardInfo fastio call and then sending the irp IRP_MJ_READ and
read that file from the disk. Now suppose i close the file and again open
that file. again FastIoQueryStandardInfo fastio call is issued and no
IRP_MJ_READ is issued. In both cases whether the file is in cache or it is
being read from disk, fastio call FastIoQueryStandardInfo returns true. Now
how will we differentiate between these two. whether the file is read from
the disk or is present in the cache.