learn_c/env_vars/README.md

Environment Variables

Ok this is kind of getting interesting.

Building

This makefile is kind of interesting. To build and name our program we just need to:

make P="env"

Ok I don't really know the magic that is going on behind that one. Notice though that you are passing that variable after calling the program. Technically, I think it's supposed to work like this:

make CFLAGS="-g -Wall" Set a makefile variable.
CFLAGS="-g -Wall" make Set an environment variable that only make and its children see.

But on my mac I am noticing only the set makefile variable method works.