[parted-devel] [PATCH] Detect Ext4 (Parted Alioth #188)

[Colin Watson]

On Fri, Jan 09, 2009 at 03:15:38PM +0000, Bryn M. Reeves wrote:
> Jim Meyering wrote:
> >Or use a file on an xfs file system as the backing store.
> >Here's a 9MB file with apparent size of over 5 exabytes:
> >
> >    $ dd if=/dev/zero of=big bs=1M count=1 seek=5T
> >    $ du -h --app big
> >    5.1E    big
> >
> >Using file systems like ext4 and xfs is fine in parted's test
> >suite, as long as you're careful to diagnose "missing support"
> >failures as "skipped" (not failing) tests.
> >
> >The advantage of doing it this way, if it works, is that the test
> >doesn't have to be run as root.
> 
> I thought since we were talking about loopback devices that this would 
> need root access anyway, but XFS is a worthy alternative too that I'd 
> not thought of and should be workable on most distros. I guess whichever 
> is easier for the test at hand really.

I suspect that Jim is suggesting that the test should just try to create
the file, and if it happens to be running on a filesystem that supports
sparse files bigger than 16TB, then it can run the full test, otherwise
it can mark it as "missing support" - rather than creating and mounting
a loopback device as part of the test suite.

-- 
Colin Watson                                       [cjwatson at ubuntu.com]