While trying to generate dependency graphs with snakefood on OSX, I grew frustrated with graphviz not rendering PNG and JPG files properly (I have a bunch of other projects running on my machine).
To avoid all this, I now run dot commands within a container instead
To run dot examples like snakefood's 30 second usage instructions to JPG:
sfood /myproject | \
sfood-graph | \
docker run -i -v `pwd`:/data enigma3319/graphviz-runner dot -Tjpg -o /data/example.jpg