This means that reading a Windows based text file, with CRLF as
line endings, the returned lines will have a trailing CR (char 13).
I can not reproduce this problem.
Everything works as expected on Windows.
Lua 5.4.3 Copyright (C) 1994-2021 Lua.org, PUC-Rio
> s="AAA\nBBB"
> io.open("file.txt", "w"):write(s):close()
true
> io.open("file.txt", "rb"):read"*a":byte(1,-1)
65 65 65 13 10 66 66 66
> f=io.open("file.txt", "r")
> f:read"*l":byte(1,-1)
65 65 65
> g=io.open("file.txt", "rb")
> g:read"*l":byte(1,-1)
65 65 65 13
