gistfile1.txt

root@ubuntu-512mb-fra1-01:~# touch $(printf '\xff\xff\xffäöü')

root@ubuntu-512mb-fra1-01:~# ls
???äöü



>>> os.listdir(b".")[1]
b'\xff\xff\xff\xc3\xa4\xc3\xb6\xc3\xbc'
>>> os.listdir(".")[1]
'\udcff\udcff\udcffäöü'
>>> print(os.listdir(".")[1])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'utf-8' codec can't encode character '\udcff' in position 0: surrogates not allowed



[1] pry(main)> Dir.glob("*")[0]
=> "\xFF\xFF\xFFäöü"
[2] pry(main)> puts Dir.glob("*")[0]
???äöü
=> nil
[3] pry(main)> Dir.glob("*")[0].valid_encoding?
=> false