Re: [coreutils] [PATCH 1/2] stat: support printing birthtime

[Eric Blake]

On 10/04/2010 03:53 AM, Pádraig Brady wrote:
> > +case $(stat --format %x a) in
> > +  *.000000000*) sleep 2;; # worst case file system is FAT
> > +  *) # FIXME: sleep .1 would be sufficient if %X showed nanoseconds
> > + sleep 1;; # should be adequate for any system with subsecond resolution
> > +esac
> > +
> > +touch a || fail=1
> > +test "x$btime" = x$(stat --format %W a) || fail=1
> > +test "x$atime" != x$(stat --format %X a) || fail=1
> > +test "x$mtime" != x$(stat --format %Y a) || fail=1
> > +test "x$ctime" != x$(stat --format %Z a) || fail=1
> > +
> > +Exit $fail
>
> Note the above test fits the pattern of "requiring a delay to pass"
> and so can use the retry_delay_ functionality used elsewhere.
> The advantage is that the delay is 1s rather than 2 on
> 1s resolution file systems like ext3.

I like it.

> +# Wait up to 2.17s for timestamps to change.
> +# ----------------------------------------
> +# iterations   file system resolution  e.g.
> +# ----------------------------------------
> +# 1            nano or micro second    ext4
> +# 4            1 second                ext3
> +# 5            2 second                FAT

And the table is nice, too.

> +# ----------------------------------------
> +check_timestamps_updated()
> +{
> +  local delay="$1"

I guess we're blindly assuming that coreutils testsuite is requiring a 
shell that supports 'local'?

--
Eric Blake   address@hidden    +1-801-349-2682
Libvirt virtualization library http://libvirt.org