tqdm should be usable as a pipe on the CLI without errors irrespective of stdin, i.e.:

cat * | tqdm >> /dev/null

should always work

• python2 -c 'print("\xff")' | python3 -m tqdm # error
• python2 -c 'print("\xff")' | python2 -m tqdm # works
• * python2 -c 'print(u"\xff")' | python3 -m tqdm # error
• * python2 -c 'print(u"\xff")' | python2 -m tqdm # error

* errors before pipe due to python2 changing encoding:
python2 -c 'print(u"\xff")' >> /dev/null also errors