If two clients ls at the same time, we get stuck in a Size() loop

[henesy]

Readdir() and Size() will be stuck in a loop if two clients call an ls at the same time.

This is due to Readdir() not tracking state, some kind of concurrent fix needs to occur that's better than the current channel-reset solution.

[henesy]

Note that while ls may break on the directory, reading/writing, etc. of the files still succeeds.