How to run a python script from IDLE interactive shell?

Question

How do I run a python script from within the IDLE interactive shell?

The following throws an error:

>>> python helloworld.py
SyntaxError: invalid syntax

Answer 1

Python3:

exec(open('helloworld.py').read())

If your file not in the same dir:

exec(open('./app/filename.py').read())

See https://stackoverflow.com/a/437857/739577 for passing global/local variables.

---

In deprecated Python versions

Python2 Built-in function: execfile

execfile('helloworld.py')

It normally cannot be called with arguments. But here's a workaround:

import sys
sys.argv = ['helloworld.py', 'arg']  # argv[0] should still be the script name
execfile('helloworld.py')

---

Deprecated since 2.6: popen

import os
os.popen('python helloworld.py') # Just run the program
os.popen('python helloworld.py').read() # Also gets you the stdout

With arguments:

os.popen('python helloworld.py arg').read()

---

Advance usage: subprocess

import subprocess
subprocess.call(['python', 'helloworld.py']) # Just run the program
subprocess.check_output(['python', 'helloworld.py']) # Also gets you the stdout

With arguments:

subprocess.call(['python', 'helloworld.py', 'arg'])

Read the docs for details :-)

---

Tested with this basic helloworld.py:

import sys
if len(sys.argv) > 1:
    print(sys.argv[1])