[systemd-devel] Is there a reason to forcefully create /etc/mtab?

[Mike Gilbert]

On Sun, Jul 6, 2014 at 1:08 PM, Ivan Shapovalov <intelfx100 at gmail.com> wrote:
> On Sunday 06 July 2014 at 13:01:22, Leonid Isaev wrote:
>> Hi,
>>
>>       I have a read-only / filesystem and /etc/mtab points to
>> /proc/self/mounts as it should.
>>       So, in systemd-215 tmpfile.d fails to create a symbolic link /etc/mtab
>> because /usr/lib/tmpfiles.d/etc.conf contains is a line "L+ /etc/mtab - - - -
>> ../proc/self/mounts".
>>       Is this intentional? Besides failing on ro /, it is also confusing
>> because /etc/mtab can be supplied by a package (in archlinux, the 'filesystem'
>> package), so why tmpfiles instead of including this symlink with systemd?
>>       The same question applies to the entire etc.conf: why does tmpfiles
>> touch /etc at all, especially if /etc is already properly set up?
>>
>> Thanks,
>>
>
> L+ (as well as any other "+" directives) only force-overwrite files if this is
> needed, e. g. if a symlink points to the wrong desination.
>

Right.

I think the path matching is a little naive; Using a simple string
comparison, "/proc/self/mounts" != "../proc/self/mounts" even though
both paths refer to the same object.