How to run Ruby/Python scripts from inside PHP passing and receiving parameters?

Question

I need to turn HTML into equivalent Markdown-structured text.

OBS.: Quick and clear way of doing this with PHP & Python.

As I am programming in PHP, som

Answer 1

Use a variable in the Ruby code, and pass it in as an argument to the Ruby script from the PHP code. Then, have the Ruby script return the processed code into stdout which PHP can read.