There's a contradiction between
On 2017-10-18 15:01:23 +0200, Martijn Dekker wrote:
> GNU stat (or gstat) makes this trivial: 'stat --file-system --format=%i
> /file/one /file/two' provides two hexadecimal file system identifiers to
> compare. But GNU stat is not standard and nowhere near ubiquitous. BSD
> 'stat' does not have any such feature.
and
On 2017-10-21 02:39:42 +0200, Martijn Dekker wrote:
> Hmm... on Linux, there can be several tmpfs mounts and they all have the
> same file system name in the first column. Example:
>
> tmpfs 33039212 0 33039212 0% /dev/shm
> tmpfs 33039212 3277180 29762032 10% /run
> tmpfs 5120 0 5120 0% /run/lock
> tmpfs 33039212 0 33039212 0% /sys/fs/cgroup
>
> Looks like we also need the mount point to uniquely identify a file
> system. A little tweak to the sed incantation accomplishes that:
>
> df -P /dev/shm /run |
> sed '1d;
> s/\([[:blank:]]\{1,\}[[:digit:]]\{1,\}\)\{4\}%[[:blank:]]\{1,\}/,/'
>
> gives
>
> tmpfs,/dev/shm
> tmpfs,/run
as with "stat --file-system --format=%i", the output is 0 for any file
on a tmpfs.
The initial question was actually not clear. First, you should define
what a file system is. If this is not what is identified by st_dev[*],
what is it?
[*] which you can get with GNU stat, or by including a small C program
in the script and compiling it.
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Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
