Appending a new line to a file in Python on Windows

Question

f = open(fn, 'ab')
f.write("\nline\n\ntest\n\ntest")

The file shows:

linetesttest

So all \\n characters are ignored. I thought appending in binary mode ('ab') should enable correct \\n behavior.

Using \\r\\n instead of \\n works. I'm on Windows.

Can anyone explain?

Answer 1

Opening it in binary mode is the problem. Don't use binary mode, and it'll do what you expect.