Makefiles that use container restarting to persist intermediates and targets

makefile

CID := .container
CONTAINER = $(shell cat $(CID) 2>/dev/null)

all: out.png

out.png: run/*
ifneq "$(CONTAINER)" ""
    docker restart $(CONTAINER)
    docker attach $(CONTAINER) || docker logs $(CONTAINER)
else
    docker run --cidfile=$(CID) -w /work -v $$PWD/run:/work \
        ipython/scipystack make $(MFLAGS)
endif
    docker cp $(CONTAINER):/output/out.png .

clean:
ifneq "$(CONTAINER)" ""
    docker rm $(CONTAINER)
endif
    rm -f out.png $(CID)

run.makefile

/output/out.png: histogram.py image.jpg /output/.exists
    python histogram.py

/output/.exists:
    mkdir -p $(dir $@)
    touch $@