On 11/15/21 10:37, Sudhip Nashi wrote:
> Turns out lseek is broken (or at least works differently) on macOS as well (https://lists.gnu.org/archive/html/bug-gnulib/2018-09/msg00054.html). Funny coincidence! I’ll take a better look later this week if I can and try to see what the exact problem is.

Thanks, I think I see the problem now.

Eventually macOS will likely get fixed to work around this 
lseek+SEEK_DATA incompatibility (as FreeBSD, Solaris, etc. all do things 
the Linux way and that's what I think will appear in the next POSIX), 
but in the meantime I attempted to work around the portability issue by 
installing the attached patch into Gnulib, and by syncing coreutils to 
the latest Gnulib.

I don't use macOS so have not tested this. Please give it a try, either 
by building from bleeding-edge coreutils on Savannah, or by building 
from the tarball temporarily here:

https://www.cs.ucla.edu/~eggert/coreutils-9.0.26-0f4d9.tar.gz

Thanks.