From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael Kerrisk (man-pages)" <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: Revised futex(2) man page for review
Date: Mon, 27 Jul 2015 13:10:43 +0200
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List-Id: linux-api@vger.kernel.org

Hi David,

On 03/31/2015 04:45 PM, Davidlohr Bueso wrote:
> On Sat, 2015-03-28 at 12:47 +0100, Peter Zijlstra wrote:
>=20
>>        The condition is represented by the futex word, which is an a=
ddress  in
>>        memory  supplied to the futex() system call, and the value at=
 this mem=E2=80=90
>>        ory location.  (While the virtual addresses for the same memo=
ry in sep=E2=80=90
>>        arate  processes  may  not be equal, the kernel maps them int=
ernally so
>>        that the same memory mapped in different locations will corre=
spond  for
>>        futex() calls.)
>>
>>        When  executing  a futex operation that requests to block a t=
hread, the
>>        kernel will only block if the futex word has the value that t=
he calling
>=20
> Given the use of "word", you should probably state right away that
> futexes are only 32bit.

So, I made the opening sentence here:

       The  condition  is  represented  by  the  futex word, which is a=
n
       address in memory supplied to the futex() system  call,  and  th=
e
       32-bit  value  at  this  memory  location.=20

Okay?

Cheers,

Michael

--=20
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/