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Date: Thu, 18 Aug 2005 22:17:57 +0400
From: Dmitry Mityugov <dmitry.mityugov@gmail.com>
To: Giorgos Keramidas <keramida@ceid.upatras.gr>
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	<43044212.20909@FreeBSD.org> <20050818125348.GG1282@flame.pc>
Cc: questions@freebsd.org
Subject: Re: man malloc
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On 8/18/05, Giorgos Keramidas <keramida@ceid.upatras.gr> wrote:
> On 2005-08-18 12:08, Sergey Matveychuk <sem@freebsd.org> wrote:
> >Chuck Swiger wrote:
> >>>What is pointer coercion? I have no pointer before malloc() returns.
> >>
> >> Right.  Well, malloc returns a (void *), but most people want to use t=
he
> >> memory malloc returns to hold their own arrays, structs, whatever, whi=
ch
> >> means that you need to be able to coerce the (void *) malloc gave you
> >> into whatever pointer type you want to actually use.
> >>
> >> So the memory malloc gives you needs to be aligned so that it's OK to =
be
> >> used for even the most restrictive datatype known to the system,
> >> commonly 8, 16, or 32 bytes.
> >
> > Pointer coercion means a type cast? I see now.
> > I read it as 'force change of pointer value' before.
>=20
> It may be surprising, but casting back and forth *MAY* change the value
> of the pointer.
...

Could you back up this assertion with an example, please?


--=20
Dmitry Mityugov, St. Petersburg, Russia
I ignore all messages with confidentiality statements

"We live less by imagination than despite it" - Rockwell Kent, "N by E"