NOTES: pcb.h has status codes but im unsure which one is supposed to represent exit? based on join-test they call exit with 1 so i think P_BAD is probs exit
i implemented joinImpl and exitImpl but if you run join-test they're failing to exit properly i think i think maybe the if statement is wrong or theyre not listennign for the exit correctly? join seems to wokr though
use https://sites.cs.ucsb.edu/~tyang_class/170w20/projects/proj2/tests.yml to reference results