# Special files found within the subuser image

For the most part, subuser specific files are found in the `/subuser` directory within the subuser image.

## Files and directories created by subuser

### `/pwd/`

This is the directory which is bind-mounted to the $PWD at launch if the `access-working-directory` permission has been set.

### `/subuser/userdirs`

This directory contains bind mounts of user directories specified by the `user-dirs` permission.

### `/subuser/execute`

This directory is bind-mounted to the directory containing the execution spool, in case the `run-commands-on-host` permission is set.

## Files and directories installed by the image creator

### `/subuser/check-for-updates`

This executable is run each time the user issues `subuser update all`. If the executable exits with a zero exit code, then the image needs to be updated. This executable is run in a special restricted container which has equivelent permissions to the containers launched by `docker build`.