2BSD/upgrade/include/install

mkdir /usr/include
mkdir /usr/include/retrofit /usr/include/retrofit/sys
cp ctype.h /usr/include/retrofit/ctype.h
cp errno.h /usr/include/retrofit/errno.h
cp pwd.h /usr/include/retrofit/pwd.h
cp retrofit.h /usr/include/retrofit/retrofit.h
cp setjmp.h /usr/include/retrofit/setjmp.h
cp sgtty.h /usr/include/retrofit/sgtty.h
cp signal.h /usr/include/retrofit/signal.h
cp sys/dir.h /usr/include/retrofit/sys/dir.h
cp sys/stat.h /usr/include/retrofit/sys/stat.h
cp sys/types.h /usr/include/retrofit/sys/types.h