So I have written a dockerfile and when I run the image the PATH is
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
I want to add another entry to the PATH so in my dockerfile I tried
ENV PATH="${PATH}:/some/new/path"
However when I tried that the PATH changed to include my personal path (with /some/new/path appended). How do I arrange it so that /some/new/path is appended without changing the rest of the PATH to my personal PATH?
The docker image is being run with --entrypoint /bin/bash and argument --norc which I'd prefer not to change if possible. 
I'm using Ubuntu 14.04.
 
    