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From: Peng Yu <pengyu.ut@gmail.com>
Date: Mon, 12 Apr 2021 11:12:50 -0500
Message-ID: <CABrM6wm3Lxj-b__WzYHYsAKbHpE9jvFg7QBSCV7TYxbYHNFVLg@mail.gmail.com>
Subject: Re: What is the point of IPC_PRIVATE of shmget?
To: Florian Weimer <fweimer@redhat.com>
Cc: Peng Yu via Libc-help <libc-help@sourceware.org>
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On Mon, Apr 12, 2021 at 11:07 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * Peng Yu via Libc-help:
>
> > I don't get the point of IPC_PRIVATE of shmget(). Since it is just
> > used by the current process, why not just use malloc?
> >
> > Can anybody give a real example in which IPC_PRIVATE must be used, but
> >  malloc or other variant of *alloc functions are not appropriate to
> > use? Thanks.
>
> shmget(2) says this:
>
> | BUGS
> |        The name choice IPC_PRIVATE was perhaps unfortunate, IPC_NEW
> |        would more clearly show its function.
>
> Does this answer your question?

No. That is just a naming issue. It is still privately used by the
current process instead of other processes.

-- 
Regards,
Peng