Re: tar extract changed since netbsd-8? (extracting sets over running system)

[Joerg Sonnenberger <joerg%bec.de@localhost>]

On Wed, Nov 13, 2019 at 07:29:59PM -0000, Christos Zoulas wrote:
> Yes, but open(O_EXCL) does not protect you against mmapped segments
> (which has the potential to kill running processes that use shared
> libraries/jar/other mapped files) or crashing in the middle of
> writing a file and leaving stuff 1/2 written. For me safety trumps
> speed (after all we don't mount our filesystems async :-), so I
> would prefer that the default is slow and safe as opposed to fast
> and unsafe, like the old pax/tar did:

O_EXCL|O_CREAT does not allow overwriting mmapped text segments. Always
writing new files and renaming doesn't make live updates safe either.
E.g. consider the case of a new symbol being updates to a shared
library.

Joerg