FILES = README Makeincl Makefile core $(wildcard *.*)
DIRS = $(filter-out $(FILES),$(wildcard *))

CLEAN = $(addsuffix .clean,$(DIRS))

.PHONY: all $(DIRS) clean $(CLEAN)

all: $(DIRS)

clean: $(CLEAN)

$(DIRS):
	cd $@ && $(MAKE)

$(CLEAN):
	cd $(basename $@) && $(MAKE) clean