$ export LC_ALL=C
$ echo "hello man" > a.txt
$ echo "hello yoda" > b.txt
$ md5sum *.txt > checksum.md5
$ md5sum -c --status checksum.md5 && echo "all files are ok"
all files are ok
$ echo 'modified!' >> b.txt
$ md5sum -c checksum.md5
a.txt: OK
b.txt: FAILED
md5sum: WARNING: 1 computed checksum did NOT match
$ md5sum -c --status checksum.md5 && echo "all files are ok"
$