From here:

$ out/Release/node -e \
    'require("child_process").fork("test/fixtures/empty.js").on("exit", console.log)'
# doesn't print, doesn't exit

parallel/test-child-process-fork3 does the same thing from a file and works fine. Dropping the 'exit' listener doesn't make a difference. @Trott points out that this goes back to at least v0.8.28.