On 16/08/2026 05:27, Collin Funk wrote:
Paul Eggert <[email protected]> writes:
Since mv ordinarily acts like 'cp --preserve=all' when copying, presumably mv
should warn in this situation if cp warns.
Also, if no mv options other than -i and -f are used, a diagnostic is
needed to conform to the spirit of POSIX, as the POSIX spec says for
this situation "If the duplication of the file characteristics fails
for any reason, mv shall write a diagnostic message to standard error,
but this failure shall not cause mv to modify its exit status."[1]
Contrary to the original bug report POSIX does not require (and
seemingly does not allow) the mv to be aborted if file characteristics
are lost in the copy, but at least the user should be warned about the
situation.
Thanks for the link. POSIX seems pretty clear here.
The attached patch should fix things. I was tempted to add another
option to "struct cp_options", but it was more unwieldy then just
setting "require_preserve_xattr" and special casing "move_mode" to not
change the exit status.
The logic looks sound.
We might get complaints for the extra warnings,
but I suppose users can `cp -a && rm` for more granular warning support.
It would be nice to add a test but it seems strace can't inject
ENOTSUP. I'll see if I can think of an alternative.
EOPNOTSUPP works
Another option is to perhaps augment tests/cp/cp-mv-enotsup-xattr.sh
BTW it would be good to reference https://bugs.gnu.org/13601
in the commit message.
thanks!
Padraig
