Add support to exchangedata(2)

[GoogleCodeExporter]

I don't know if it's possible, but it'd be nice if support for exchangedata() 
was added to macfuse, 
which will enable filesystems to properly handle safe save.

Original issue reported on code.google.com by ofri.wol...@gmail.com on 1 Apr 2008 at 1:57

[GoogleCodeExporter]

Sorry, this was meant to be an enhancement type issue.

Original comment by ofri.wol...@gmail.com on 1 Apr 2008 at 1:58

[GoogleCodeExporter]

Sorry, this won't be done for MacFUSE in its current form. Perhaps if some day 
MacFUSE evolves into something 
very different... but that's another discussion.

Original comment by si...@gmail.com on 1 Apr 2008 at 5:12

• Changed state: WontFix

[GoogleCodeExporter]

I believe I explained myself poorly. Sorry.
I'm currently at the early stage of writing a MacFuse based filesystem which 
does some processing on file 
modifications. Based on write calls the FS determines the data that changed and 
processes it, but this won't 
work for safe saves based on exchangedata(). If I understand correctly, 
exchangedata() calls into the FS and 
sees if it supports this capability, so ideally, I'd like to be able to have an 
exchangedata callback in my FS in 
order to properly handle safe saves. If I had an exchangedata callback, I could 
then diff the file with its 
replacement and find what changed, but without exchangedata support safe save 
just does delete + move 
which is tricky at best to detect.

If this request is still not appropriate to MacFuse, I'd be happy to know why 
as I can't really think of a reason 
myself.

Original comment by ofri.wol...@gmail.com on 2 Apr 2008 at 9:15