fslint (findup) fails to check paths with spaces

[KIAaze]

Test case:

# create a test case
TEMPDIR=$(mktemp -d)
echo "${TEMPDIR}"
cd ${TEMPDIR}
mkdir "a b" "c d"
echo test > "an example.txt"
cp "an example.txt" "a b"
cp "an example.txt" "c d"

# fdupes from the Debian/Ubuntu repositories works fine:
fdupes --recurse "${TEMPDIR}"

# fails:
findup "${TEMPDIR}"

Example output:

md5sum: an: No such file or directory
md5sum: example.txt: No such file or directory
md5sum: a: No such file or directory
md5sum: b/an: No such file or directory
md5sum: example.txt: No such file or directory
md5sum: c: No such file or directory
md5sum: d/an: No such file or directory
md5sum: example.txt: No such file or directory

I started having this problem with the fslint package from Kubuntu 19.10 and it persisted in Kubuntu 20.04 (where I had to install the old version using this: https://askubuntu.com/questions/1233710/where-is-fslint-duplicate-file-finder-for-ubuntu-20-04 )
But the problem is still there with the latest version from this repository.

fslint repository version tested:

$ git log -1 --format="%H"
c298bfb809d0f773e9226a68d438f19bfe752293
$ findup --version
FSlint 2.47

System infos:

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 20.04 LTS
Release:        20.04
Codename:       focal
$ bash --version
GNU bash, version 5.0.16(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.