Python os.chdir is modifying the passed directory name

Question

I am trying to change the current working directory in python using os.chdir. I have the following code:

import os

os.chdir("C:\Users\Josh\Desktop\20130216")

However, when I run it, it seems to change the directory, as it comes out with the following error message:

Traceback (most recent call last):
File "C:\Users\Josh\Desktop\LapseBot 1.0\LapseBot.py", line 3, in <module>
os.chdir("C:\Users\Josh\Desktop\20130216")
WindowsError: [Error 2] The system cannot find the file specified
  'C:\\Users\\Josh\\Desktop\x8130216'

Can anyone help me?

Solution 1

Python is interpreting the \2013 part of the path as the escape sequence \201, which maps to the character \x81, which is ü (and of course, C:\Users\Josh\Desktopü30216 doesn't exist).

Use a raw string, to make sure that Python doesn't try to interpret anything following a \ as an escape sequence.

os.chdir(r"C:\Users\Josh\Desktop\20130216")

Solution 2

You could also use os.path.join (documentation). Example:

os.chdir(os.path.join('C:\Users\Josh\Desktop', '20130216'))

This is more elegant + it's compatible with different operating systems.

Solution 3

This should work -

os.chdir("C:\Users\Josh\Desktop\\20130216")

Comments

[Stephan]

why do you need the second backslash?

[masnun]

@Stephan Because "\201" is a character. We need to escape the backslash to tell python that you didn't mean that but it's just another backslash (in fact path separator here)

[Martijn Pieters]

Or use forward slashes, or double the backslashes.

[voithos]

@MartijnPieters: Yep, good point. Python can correctly understand paths like C:/Users/Josh/... on Windows.

[Nabin]

what does the "r" do??

[voithos]

@Nabin It's how you define a raw string, i.e. a string without any escape sequences