django os.path.dirname（__ file__）

Question

I am doing exercises from book: http://www.tangowithdjango.com/book17/chapters/templates_static.html

and I have problem with this code:

import os

print __file__
print os.path.dirname(__file__)
print os.path.dirname(os.path.dirname(__file__))

It shold print dir names. Instead of that it prints first line ( filename) but 2nd and 3rd line are also printed but empty.

I get this behavior with Python 2.7 on Windows 7 and Ubuntu 14.04

EDIT: with this code i get absolute path with os.path.dirname(__file__) :

import os
import django
import settings

print settings.BASE_DIR

What is the difference if the same code is imporeted from settings.py and coded directly?

Answer 1

The __file__ value in the main script can be relative to the current working directory. Use os.path.abspath() to make it absolute first:

print os.path.abspath(__file__)
print os.path.dirname(os.path.abspath(__file__))
print os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

Answer 2

This is the absolute path of the directory where the program resides which is what you want I believe.

os.path.abspath(os.path.dirname(__file__))

This is the parent directory of the program

os.path.join(os.path.dirname(__file__), 'some_directory')

This is the abbreviated directory where the program resides

os.path.dirname(os.path.realpath(__file__))