архив создан так
adb exec-out 'cd /external_sd; tar \
--exclude=./data/*/*cache*/* --exclude=./system/*cache*/* --exclude=./user*/*/*/*cache*/* --exclude=./media/*/Android/data/*/*cache* --exclude=./cache/* --exclude=./dalvik-cache/* --exclude=./resource-cache/* --exclude=./data/*/*/*Cache/* --exclude=./user/*/*/*/*/GPUCache/* --exclude=backup.tar.bz2 \
-cpvf - ./ 2>/tmp/tar.log' | pv | xz -T4 -z > external_sd.tar.xz
попытка распаковать ./user/ из архива
LANG=C tar -xpv -f ../external_sd.tar.xz ./user/
tar: Skipping to next header
tar: ./user: Not found in archive
tar: Exiting with failure status due to previous errors
tar twrp
~ # tar
BusyBox v1.22.1 bionic (2021-04-05 12:23 +0000) multi-call binary.
Usage: tar -[cxtzJjahmpvO] [-X FILE] [-T FILE] [-f TARFILE] [-C DIR] [FILE]...
Create, extract, or list files from a tar file
Operation:
c Create
x Extract
t List
f Name of TARFILE ('-' for stdin/out)
C Change to DIR before operation
v Verbose
z (De)compress using gzip
J (De)compress using xz
j (De)compress using bzip2
a (De)compress using lzma
O Extract to stdout
h Follow symlinks
m Don't restore mtime
exclude File to exclude
X File with names to exclude
T File with names to include
p Store SELinux contexts
