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From:   Florian Weimer <fweimer@redhat.com>
To:     Palmer Dabbelt <palmer@sifive.com>
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Subject: Re: Add a new fchmodat4() syscall, v2
References: <20190717012719.5524-1-palmer@sifive.com>
Date:   Tue, 09 Jun 2020 15:52:17 +0200
In-Reply-To: <20190717012719.5524-1-palmer@sifive.com> (Palmer Dabbelt's
        message of "Tue, 16 Jul 2019 18:27:15 -0700")
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* Palmer Dabbelt:

> This patch set adds fchmodat4(), a new syscall. The actual
> implementation is super simple: essentially it's just the same as
> fchmodat(), but LOOKUP_FOLLOW is conditionally set based on the flags.
> I've attempted to make this match "man 2 fchmodat" as closely as
> possible, which says EINVAL is returned for invalid flags (as opposed to
> ENOTSUPP, which is currently returned by glibc for AT_SYMLINK_NOFOLLOW).
> I have a sketch of a glibc patch that I haven't even compiled yet, but
> seems fairly straight-forward:

What's the status here?  We'd really like to see this system call in the
kernel because our emulation in glibc has its problems (especially if
/proc is not mounted).

Thanks,
Florian