How to open python scripts directly by typing in their name in terminal (Mac OS X)

Question

I'm working on installing django and running it on my system.

I have a problem though, in this tutorial creating a project is explained by running the command

django-admin.py startproject mysite

My issue is that this doesn't work. I changed to the directory where django-admin.py is located and ran the command

chmod +x django-admin.py

with no results. I tried adding the directory with the file to my path without results. I ended up fixing my problem with this command

python /location/of/django-admin.py startproject mysite

which yielded the outcome I expected. My problem is: What do I need to change/configure such that command

django-admin.py startproject mysite

would be sufficient?

Here are some experiments:

21:09~/Desktop/HI/NSN/Polls > django-admin.py startproject mysite
-bash: django-admin.py: command not found
21:09~/Desktop/HI/NSN/Polls > ./django-admin.py startproject mysite
-bash: ./django-admin.py: No such file or directory
21:09~/Desktop/HI/NSN/Polls > python django-admin.py startproject mysite
python: can't open file 'django-admin.py': [Errno 2] No such file or directory
21:09~/Desktop/HI/NSN/Polls > /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py startproject prufa1
-bash: /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py: /opt/local/bin: bad interpreter: Permission denied
21:09~/Desktop/HI/NSN/Polls > sudo /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py startproject prufa1Password:
sudo: unable to execute /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py: Permission denied
21:09~/Desktop/HI/NSN/Polls > sudo /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py startproject prufa1sudo: unable to execute /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py: Permission denied
21:09~/Desktop/HI/NSN/Polls > python /opt/local/lib/python2.4/site-packages/django/bin/django-admin.py startproject prufa1
21:09~/Desktop/HI/NSN/Polls > ls
mysite prufa1

Final edit: The problem is solved, see Ian C's answer for the right solution. Thank you everyone for helping my out, this was very fast!

Answer 1

There's a slightly more generic version of @Matt Jenkins hashbang (!#) tip you can use to make the script a little more portable. Make sure the first line in the file is:

#!/usr/bin/env python
...everything else...

That says "look for a program named python by searching my PATH and run the rest of this script with that program".

You'll also need to set the execute bit on the script with:

chmod +x django-admin.py

I mention this for completeness, noting that you've already done that.

Finally, the PATH variable doesn't actually contain . in it (the current working directory). That's a safety precaution and I don't recommend changing that setup (it keeps you from calling ./rm when you meant the shell's rm for example). So you need to call the script with:

 ./django-admin.py startproject mysite

That says "look in the current working directory for django-admin.py" instead of "search the PATH variable" which is what happens if you omit the ./ part.

Answer 2

The first line in the file should contain the program that runs the script prefixed by #! (known as hashbang)

For example:

#!/path/to/python
...python code follows...

Then you can set the executable bit on the file and the shell will interpret it as a script using the program found in the first line as the interpreter.

This is often used with shell scripts, for example:

#!/bin/sh

for FILE in `ls`
{
    echo "Filename: ${FILE}"
}

Answer 3

1. Select the file in the Finder by clicking it once.

2. From the File menu, select Get Info.

3. In the Info window, click the triangle next to "Open with:" to expand that section of the window.

4. From the pull-down menu that appears, select the application you wish to use to open the file.

— Source: Indiana University - KB: How do I assign an application to open certain file types?

Answer 4

When you change the file django-admin.py permissions, you have to write this:

sudo chmod +x django-admin.py

Works for me