"readline()" omitted '\r' in win32 for dos format text file

[Peter Otten]

Newgene wrote:

> I have python2.3 installed on win2k. I noticed that when I open a
> dos format text file (eol is '\r\n'), readline() always returns a line
> ending with '\n' only, not '\r\n'. While I read the same file on unix,
> it returns a line ending with '\r\n' correctly.
> This makes me difficult to determine the format of a text file, dos or
> unix.
> 
> Is this a bug or intended behavior? If not a bug, then how to
> determine the format of a text file?

It's not a bug. On windows, files are opened in text mode by default.

Opening a file in binary mode 

file(name, "rb") 

will preserve the line endings regardless of platform while opening it in
"universal" mode 

file(name, "rU") 

will normalize all line endings to "\n". 

Peter