O_DIRECT support in dd

[Phillip Susi]

I searched the archives and found a thread from over a year ago talking 
about adding support to dd for O_DIRECT, but it is not documented in the 
man pages.  Did the man pages not get updated, or did this patch not 
make it in?

If O_DIRECT is supported, but not documented, then I wonder: does dd use 
aio so as to keep the IO pipelined, since a blocking read/write would 
only be able to access one file/disk at a time?