# LibTmux::ControlSubscription#diagnostics

- **Module:** LibTmux
- **Package:** libtmux
- **Language:** Ruby
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-ruby/blob/d8ce4bbee0ca7748a81929f81f7d8d07f8c51267/gems/libtmux/lib/libtmux/control.rb#L163
- **Page:** https://libtmux.org/en/ruby/v0.1.0.alpha.3/reference/libtmux-controlsubscription-diagnostics/

```
def diagnostics: () -> {
  queued_events: ::Integer,
  retained_event_bytes: ::Integer,
  gap_pending: bool,
  overflowed: bool,
  closed: bool,
  mode: :reliable | :tail,
  limits: { max_bytes: ::Integer, max_events: ::Integer }
}
```

Returns frozen local buffer state. A reliable overflow keeps its prefix
readable; explicit close discards the prefix and pending loss report.

Behavior contract: Diagnostics.