Asynchronous I/O on UNIX? Request for status..

[Richard Friedman]

I understand that asynchronous I/O is not a part of standard
Unix.  (By asynch I/O I mean the capability of a program to
startup an I/O operation, such as a binary read from disk to
memory, and continue to use the cpu while the I/O operation
is in progress.. at some later time the program requests
status on the operation and waits until the read has 
completed if it hasn't already).  Asynch I/O is an important
part of most large scientific mainframe systems and many
applications codes require asynch I/O (e.g. CDC BUFFERIN/OUT)
to efficiently overlap I/O and computation.

As more and more mainframe systems are moving to UNIX, I am
very interested in finding out how asynch I/O is being implemented
on these systems.

Please reply to me directly if you have information, and I will
digest it and spew it all back into net.unix later.  Thanx.
-- 
     
    [rchrd] = Richard Friedman
              Pacific-Sierra Research, 2855 Telegraph #415
              Berkeley, CA 94705 (415) 540 5216
    UUCP: {hplabs,ptsfa,dual}!well!rchrd