echo "--format=posix"
tar --create --verbose --file=reference/posix.tar --owner=1 --group=2 --format=posix reference/res/

echo "--format=gnu"
tar --create --verbose --file=reference/gnu.tar --owner=1 --group=2 --format=gnu reference/res/

echo "--format=v7"
# v7 can't store long names at all
tar --create --verbose --file=reference/v7.tar --owner=1 --group=2 --format=v7 reference/res/test.txt

echo "--format=ustar"
tar --create --verbose --file=reference/ustar.tar --owner=1 --group=2 --format=ustar reference/res/

echo "truncated --format=posix"
tar --create --file - --owner=1 --group=2 --format=posix reference/res/ | head --bytes=1k > reference/bad_truncated.tar

# Note: The truncated headers were generated by creating a 9 GiB blob:
#  dd if=/dev/zero of=zeroes ibs=1G count=9
# Then, I ran
#  tar --create --format=posix zeroes | head -q -c 1536 > reference/headers/large_posix.tar