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From: Florian Weimer <fweimer@redhat.com>
To: Peng Yu via Libc-help <libc-help@sourceware.org>
Subject: Re: What is the point of IPC_PRIVATE of shmget?
References: <CABrM6w=oBUEcrWHTc-Q_ksoxwpHYCeLZnz0F+jG9bbeKMSrGoA@mail.gmail.com>
Date: Mon, 12 Apr 2021 18:07:46 +0200
In-Reply-To: <CABrM6w=oBUEcrWHTc-Q_ksoxwpHYCeLZnz0F+jG9bbeKMSrGoA@mail.gmail.com>
 (Peng Yu via Libc-help's message of "Mon, 12 Apr 2021 10:54:20 -0500")
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* 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?

Thanks,
Florian