Adding files from other branch

examples/Makefile

@@ -3,7 +3,7 @@ SRCDIR = ..
 # Test programs to compile, and a list of sources for each.
 # To add a new test, put its name on the PROGS list
 # and then add a name_SRC line that lists its source files.
-PROGS = cat cmp cp echo halt hex-dump ls mcat mcp mkdir pwd rm shell \
+PROGS = cat cmp cp echo exit halt hex-dump ls mcat mcp mkdir pwd rm shell \
 	bubsort insult lineup matmult recursor my
 
 # Should work from project 2 onward.
@@ -11,6 +11,7 @@ cat_SRC = cat.c
 cmp_SRC = cmp.c
 cp_SRC = cp.c
 echo_SRC = echo.c
+exit_SRC = exit.c
 halt_SRC = halt.c
 hex-dump_SRC = hex-dump.c
 insult_SRC = insult.c