Марк Коренберг added the comment: https://docs.python.org/3.5/library/io.html?highlight=stringio#id3 :
Also, TextIOWrapper.tell() and TextIOWrapper.seek() are both quite slow due to the reconstruction algorithm used. What is reconstruction algorightm ? Experiments show, that seek() and tell() returns values of count of bytes (not letters). #!/usr/bin/python3.5 import tempfile with tempfile.TemporaryFile(mode='r+t') as f: l = f.write('привет') print(l, f.tell()) # "6 12" f.seek(3) f.write('прекол42') f.seek(0) print(f.read()) # raise UnicodeDecodeError So, please reopen. Issue is still here. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue25849> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com