Read the paper https://docs.freebsd.org/44doc/psd/20.ipctut/paper.pdf

Create C programs by copy/paste'ing each of the programs in the figures.
You should end up with C programs as listed in the manifest file.
Each file should compile with gcc with NO warnings and should run properly.
You will need to fix some things in the programs to make them compile
without warnings.

Note that there is a correct working version of each program in this directory.
These all have "jeff" in the file name.

Points - 1 point per program