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From: Julian Elischer <julian@freebsd.org>
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Subject: Re: FreeBSD FUSE calls truncate() on read-only files
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On 2/25/15 5:34 AM, Eggert, Lars wrote:
> Hi,
>
> this came up when trying to port tup (https://github.com/gittup/tup) to FreeBSD.
>
> Even though we are opening the file read-only with cat, FUSE calls truncate() on it, which modifies its mtime and this screws up tup. See https://github.com/gittup/tup/issues/198
>
> Anyone know why FreeBSD's FUSE is doing this?

nope but it has lots of other bugs..
for example it caches information when it shouldn't, even from 
'dynamic' file systems
We had to change the code to disable  it as our data is synthetic and 
might change between reads.
fstat info is also cached and confused our apps mightily.


>
> Thanks,
> Lars