editline/history.h and editline/readline.h not found/working on OSX when trying to compile with developer tools installed already

Question

I am working on this tutorial on building your own LISP (http://www.buildyourownlisp.com/chapter4_interactive_prompt) and for some reason when I try to compile I get this:

Answer 1

The solution for those following along on FreeBSD (might work on other Unices as well):

#include 
#include 

#include 
#include 

...

And run:

$ cc test.c -Wall -std=c99 -lreadline -o test

Without "-lreadline" in the compile step it is not linked in and you will get errors about undefined reference to "readline" function.