Keeping the current behavior for exec, i.e., inheriting variables from main process. New variables will be added to current ones. If there's already a variable with that name it will be overwritten. Example of usage: docker exec -it -e TERM=vt100 <container> top Closes #24355. Signed-off-by: Jonh Wendell <jonh.wendell@redhat.com> Upstream-commit: e03bf1221ee2c863f25a57af4d415e2d8ff4f26c Component: engine