From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christopher Covington <cov@codeaurora.org>
Subject: Re: [PATCH] mm: msync: require either MS_ASYNC or MS_SYNC
Date: Thu, 03 Apr 2014 07:51:30 -0400
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On 04/03/2014 04:25 AM, Michael Kerrisk (man-pages) wrote:

> I think the only reasonable solution is to better document existing
> behavior and what the programmer should do. With that in mind, I've
> drafted the following text for the msync(2) man page:
>=20
>     NOTES
>        According to POSIX, exactly one of MS_SYNC and MS_ASYNC  must =
 be
>        specified  in  flags.   However,  Linux permits a call to msyn=
c()
>        that specifies neither of these flags, with  semantics  that  =
are
>        (currently)  equivalent  to  specifying  MS_ASYNC.   (Since Li=
nux
>        2.6.19, MS_ASYNC is in fact a no-op, since  the  kernel  prope=
rly
>        tracks  dirty  pages  and  flushes them to storage as necessar=
y.)
>        Notwithstanding the Linux behavior, portable, future-proof app=
li=E2=80=90
>        cations  should  ensure  that they specify exactly one of MS_S=
YNC
>        and MS_ASYNC in flags.

Nit: MS_SYNC or MS_ASYNC

Christopher

--=20
Employee of Qualcomm Innovation Center, Inc.
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