Provide access to devcontainer.local_folder via an environment variable

[zfields]

I have to call out to a program that resides outside my container. It wants to work on a source file I'm updating in my dev container, but I don't know how to describe the host file path to the external program from inside my container without hardcoding the file path.

I noticed in the container launch logs, you are actually keeping inventory of the folder that maps to workspaces/<folder> as devcontainer.local_folder.

Start: Run: docker run --sig-proxy=false -a STDOUT -a STDERR --mount type=bind,source=/home/zak/Development/GitHub/blues/note-zephyr,target=/workspaces/note-zephyr --mount type=volume,src=vscode,dst=/vscode -l devcontainer.local_folder=/home/zak/Development/GitHub/blues/note-zephyr -l devcontainer.config_file=/home/zak/Development/GitHub/blues/note-zephyr/.devcontainer/devcontainer.json --net=host --device=/dev/bus/usb/ --entrypoint /bin/sh vsc-note-zephyr-b0bf7870899f9417cf096d9b5dfba90b-uid -c echo Container started
Container started

-l devcontainer.local_folder=/home/zak/Development/GitHub/blues/note-zephyr

Is there a way I can read that metadata from inside the container (specifically from tasks.json) today? If not, I would like to request this as a feature.

CONTEXT: I am trying to send a command to OpenOCD, so it can flash a binary to an embedded device connected over USB. OpenOCD executes outside the container, because I cannot provide access to USB from the container in a platform independent way. The toolchain required to compile the binary lives inside the container, but OpenOCD needs to know the binary location (with respect to the host file system) before it can flash the binary to the embedded device.

[zfields]

I did a bunch of research and I figured out how to do it, but it seems a little kludgey...

devcontainer.json

    "remoteEnv": {
        "hostWorkspaceFolder":"${localWorkspaceFolder}"
    },

Now I can refer to the workspace folder on the host as ${hostWorkspaceFolder}. This works fine, but I maintain that it would be nice to have an additional predefined variable to support this out of the box.