bug#51433: cp 9.0 sometimes fails with SEEK_DATA/SEEK_HOLE

[Pádraig Brady]

On 30/10/2021 02:24, Paul Eggert wrote:
> On 10/28/21 12:11, Paul Eggert wrote:
> > Wait - lseek returns a number less than -1?! We could easily check for
> > that FreeBSD bug, perhaps as an independent patch; this shouldn't
> > require any extra syscalls.
>
> I installed the attached patch to do this. This doesn't fix coreutils
> bug#51433; it merely makes 'cp' and similar programs more likely to
> detect and report the FreeBSD 9.1 bug you mentioned.

On further inspection it seems the bug is in truss :/
I.e. the only bug on FreeBSD 9.1 is that the SEEK_DATA takes ages,
but the returned values are correct.
I.e. SEEK_DATA was returning 1099511595008 in this case
which truss was reporting in 32 bit rather than 64 bit.
I see other inconsistencies in truss output,
so it can only be relied on for what syscall was called,
rather than what was passed/returned.

Given this patch doesn't change any operation,
it may be best to revert to avoid the complexity?

cheers,
Pádraig