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Date:   Tue, 26 Sep 2023 16:13:53 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Florian Weimer <fweimer@redhat.com>
Cc:     Miklos Szeredi <mszeredi@redhat.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-api@vger.kernel.org, linux-man@vger.kernel.org,
        linux-security-module@vger.kernel.org, Karel Zak <kzak@redhat.com>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Amir Goldstein <amir73il@gmail.com>
Subject: Re: [RFC PATCH 2/3] add statmnt(2) syscall
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> I also don't quite understand the dislike of variable-sized records.
> Don't getdents, inotify, Netlink all use them?  And I think at least for
> Netlink, more stuff is added all the time?

Netlink is absolutely atrocious to work with because everything is
variable sized and figuring out the correct allocation size is a
complete nightmare even with the "helpful" macros that are provided.

The bigger problem however is the complete untypedness even of the most
basic things. For example, retrieving the mtu of a network interface
through netlink is a complete nightmare. getdents, inotify, fanotify,
open_by_handle_at()'s struct fiel_handle are all fine. But let's
absolutely not take netlink as a model for anything related to mounts.

And no one is against again variable sized records per se. I think we're
coming to a good compromise here.