Byte at a time disk IO

[lvs at ndm20]

Since I have no access to any UNIX source code, and this aspect is
not very well documented, I will ask "Those who know where from they speak".

The point in question is byte at a time disk i/o.  Does it really work.
Can n processes be reading/writting from/to different bytes in the same
locality (block) without wiping each other out.  In another guise, if you
set a file mode to "unbuffered", is it REALLY unbuffered to the point of
being able to write individual bytes without possibly stomping on another
process reading the byte next to it.

I would like information about as many different versions of UNIX as I can
get.  Please mail to me directly, and I will summarize the relevant details.
If any are received.

Thanks in advance.

Larry V. Streepy Jr.
Nathan D. Maier Consulting Engineers
VOICE:  (214)739-4741
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