Device files are not supported

[ebkalderon]

It appears that reading from and writing to device files is not supported via sandboxfs and osxfuse on macOS. Given the example command below:

sandboxfs --mapping ro:/:/ --mapping rw:/dev:/dev ./mnt

The following attempts to write to any device file in the mounted /dev subdirectory fail with the following error:

$ cd mnt
$ echo hi > ./dev/null
-bash: echo: write error: Operation not permitted
$ head -1 < ./dev/random
head: Error reading stdin

I have not verified if the same limitation exists on Linux as well at the time of writing, but it nevertheless would be quite nice if sandboxfs supported binaries or scripts which wrote to /dev/null if the user requested that the device file be mounted, for example.