I'm trying to write a little docker file that sets a User and just echos the current user as a little example to prove to myself it is working. I've tried a number of variants and couldn't find much help in the documentation.
FROM ubuntu
USER daemon
# ENTRYPOINT ["echo", "$USER"]
# just gives "$USER"
# ENTRYPOINT ["echo", "-e", "${USER}"]
# just gives "$USER"
# ENTRYPOINT echo $USER
# gives empty string
# ENTRYPOINT ["/bin/echo", "$USER"]
# just gives "$USER"
I'm running docker build .
on the dockerfile and then running docker run <image-id>
and getting the results
Expected result is daemon
, or without the USER daemon
line, I expect root
. Probably a really simple answer.