`pidcat` installed via `brew` no longer works on macOS 12.3, due to Python 2 having been removed

Hey!

First off, thank you for the great util, Jake. And all the other cool stuff you’ve built througout the years.

I’m having an issue where pidcat, installed from brew, can no longer run on macOS 12.3. I believe this is because of Python 2 having been removed on this version of macOS.

I’m getting the following output, when attempting to run pidcat:

~ pidcat
zsh: /opt/homebrew/bin/pidcat: bad interpreter: /usr/bin/python: no such file or directory

This in turn is caused by https://github.com/JakeWharton/pidcat/blob/44b4a106bb25776cbb551044b303520a07a51c1e/pidcat.py#L1:

#!/usr/bin/python -u

On macOS 12.3, /usr/bin/python does not exist - only /usr/bin/python3.

Running on the latest development version (as listed in the current README.md, does not solve the issue, as it still looks for python, which still does not exist.

One alternative that could resolve the issue would be to update pidcat to explicitly try to use python3, but this would have some less desirable backwards compatibility issues, perhaps.

[rafaelmaeuer]

I was able to fix it with following steps:

# Use pyenv to install python2 with:
brew install pyenv
pyenv install 2.7.18
 
# Optionally set it to your global default:
pyenv global 2.7.18
 
# Create Alias in .zshrc
alias python=/Users/<user>/.pyenv/versions/2.7.18/bin/python
 
# Reload shell and test
source .zshrc
python -V

# Find Pidcat script
which pidcat

# Edit shebang line
sudo nano path/to/pidcat

# Replace first line:
#!/Users/<user>/.pyenv/versions/2.7.18/bin/python -u

[jox]

Simply symlinking python to python3 isn’t a good idea. First of all, it is not “simple” on macOS due to SIP since OS X 10.11. Secondly, it might produce confusion and unexpected results on other ends (e.g. Python things that expect python to be Python 2).

The real solution would be to fully depend Pidcat on Python 3. It’s also about time, since Python 2 has long-since reached end of life.