How do I call a python script on the command line like I would call a common shell command, such as cp?

Question

Suppose I've got a script I can run with:

python hello_world.py
>>> "Hello, world!"

How can I configure hello_world.py to be executable without 'python' or './' :

hello_world
>>> "Hello, word!"

EDIT: Thanks all for the suggestions! The shebang and path solution and the python package solution both worked. I checked the python package solution because I liked the added features of tacking the script onto my path via pip install -e . without hand-editing my path variable and catching the script during pip freeze > requirement.txt calls.

Answer 1

If you're on Linux or Unix, at the top your file, it's typically something like

#!/bin/python

or

#!/usr/bin/python

You'll need execution perms to run the file as well, in that manner. Use chmod

chmod +x hello_world.py

If you're not running as root, you may require sudo, and that would be

sudo chmod +x hello_world.py

And then attempt to run with

./hello_world.py 

if you must dispense with the ./:

alias ./hello_world.py=hello_world 

Answer 2

One workaround would be to use aliases, ie alias hello_world='python hello_world.py'

This will of course only work in the folder where hello_world.py lives, but alias hello_world='python full/path/to/hello_world.py' would work anywhere.

This will only work for your bash session, but adding the alias command to your ~/.bashrc will make it permanent.

Answer 3

You can do the following:

• Make the script executable (using chmod +x hello_world.py)
• Rename it to hello_world
• Move it to a directory that is in your PATH (eg /usr/bin)

Answer 4

1. If the ~/bin directory is not there, create it and move the python script to this directory.
2. Rename hello_world.py to just hello_world

3. At the beginning of the script, add

     #!/usr/bin/env python 

4. then

     chmod +x hello_world 

Note: If you are creating the ~/bin directory in Ubuntu , logout and login again (to run the ~/ .profile file). The default ~/.profile will automatically add the ~/bin directory to your path.

Answer 5

It only needs to be readable for "python hello_world.py" to work. You can chmod +x hello_world.py to make it executable. Append '.' to your PATH environment variable if you need the "./"

Answer 6

Another way would be install the script using setup.py and configure entrypoints like this.

entry_points={'console_scripts': ['hello_world = hello_world:main']},

Answer 7

I just did this for the first time a few hours ago. What you can do is turn your python script into a 'package', then install that package.

I followed this tutorial and it worked for me. If you follow it you will be able to type 'runner' on the cmd line and your script will run.

Answer 8

You could create a python script in your PATH (or add it to your own PATH).

I'm assuming you don't have a $HOME/bin , if you do skip this -

mkdir $HOME/bin

next, create $HOME/bin/hello_world

#!/usr/bin/env python

print "Hello, World!"

then,

chmod +x $HOME/bin/hello_world
export PATH=$PATH:$HOME/bin

Then you can,

$ hello_world
Hello, World!