Doubt on mmap file backend

Poul-Henning Kamp phk at
Wed Sep 19 11:42:50 UTC 2018

In message <CAC3PTxJqHqzH_9dsN8Q7jhLOonVc7CGQRscwwP86hDHGykj97w at>, Prem Kumar writes:

>Is it possible that mmap content can differ on read after write or is this
>the problem happening because read is called before the msync().Sorry ,it
>is very generic question ..Wanted to know if any idea on the behavior.

If you mean "read by another process", then yes.  Only kernels with
integrated VM/buffers provide consistency without msync.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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