# Requirement change

The audit team wants file destinations to roll over: once a file has taken a fixed number of
lines, stop writing to it and start a new one, so no single file grows without bound and old
files can be archived independently.

Concretely:

- A destination should accept a maximum number of lines. Once it has written that many, the
  very next line goes to a new, empty destination instead — think of it as a fresh file, though
  what "a file" means underneath is entirely up to you.
- Nothing is lost in the switch: the line that triggers the rollover still gets written, just to
  the new destination rather than the old one.
- Every line still ends up written exactly once, in the order it was logged.
- This is a property of that one destination. Nothing about logging itself, or about any other
  destination, needs to know rollover is happening.
