Working directory

Using cd is not persisted across steps.

But setting working directory with WORKDIR is.

Set working directory

This is useful to a working directory for subsequent commands in the image build or container running. Especially if you start in interactive mode and want to start at an appropriate directory.

If the directory does not exist, you must create it using `mkdir.

Dockerfile

RUN mkdir /root/foo
WORKDIR /root/foo

Dockerfile

RUN mkdir /usr/src/app
WORKDIR /usr/src/app

Though, you can set up working directory and then use COPY to add something there and the directory will be created, without the need for mkdir.

Given app in the current directory, the app directory will be copied to where the working directory expects it to be.

Dockerfile

WORKDIR /usr/src/app
COPY . .

I read that using absolute paths is preferred in a container over a path like ~/foo.