Make file executable in UNIX-style command line

make-file-executable.md

Make file executable in UNIX-style command line

Recently I started to learn Python. My first experiment consisted of a simple script named script.py to print the classic "Hello World!" message. To make the file executable, I added the shebang at the top of the file.

Contents in script.py:

#!/usr/bin/env python3

print('Hello World!')

However, when I try to run the script in the terminal, the script doesn't work.

After some research I find out that I need to flag the file as exectuable in order to enable bash to execute the file.

Bash command to flag the file as executable:

chmod u+x script.py

Now I can happily invoke ./script.py in the command line and see the printed message "Hello World!" in the terminal.

References:

• https://en.wikipedia.org/wiki/Shebang_(Unix)
• https://stackoverflow.com/questions/22222473/shebang-doesnt-work-with-python3