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[Python-Dev] best place for an atomic file API

Most users don't need a truly ACID write, but implement their own
best-effort function. Instead of having a different implement in each
project, Python can provide something better, especially when the OS
provides low level function to implement such feature.


2012/2/16 "Martin v. L?wis" <martin at v.loewis.de>:
> I'm not so sure that "atomic writes" is a useful concept. I haven't seen
> a proposed implementation, yet, but I'm doubtful that truly ACID
> writes are possible unless the operating system supports transactions
> (which only Windows 7 does). Even if you are ignoring Isolation,
> Atomic already is a challenge: if you first write to a tempfile, then
> rename it, you may end up with a state tempfile (e.g. if the process
> is killed), and no rollback operation.
> So "atomic write" to me promises something that it likely can't
> deliver. OTOH, I still think that the promise isn't actually asked
> for in practice (not even when overwriting bytecode files)