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Date: Sun, 27 Sep 2026 02:02:29 -0400 Message-ID: <5193732.31r3eYUQgx@daniel-desktop3> In-Reply-To: <20241021-tonyk-tmpfs-v8-6-f443d5814194@igalia.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Upon successfully mounting via `sudo mount -t tmpfs -o casefold test /mnt`, I cannot find a read-only way to determine whether this option is enabled. `mount`, `cat /proc/mounts`, and `cat /proc/mountinfo` only display "rw", "relatime", and "inode64", never "casefold" for both with and without `-o casefold`. The only way on 7.0.0-34-generic to test I found is `mkdir test ; chattr +F test ; echo $?`, but that isn't atomic. Which command can determine, without writing anything, whether someone or some program specified `-o casefold`? If absent, I suggest adding the missing info to `/proc/mounts`, likely `mm/shmem.c:shmem_show_options`. Link: https://lore.kernel.org/r/20241021-tonyk-tmpfs-v8-6-f443d5814194@igalia.com