pub type EventHandlerFn = extern "C" fn(event: StablePluginEvent, user_data: *mut c_void) -> i32;Expand description
Handler fn pointer registered via register_event_handler(tag, handler).
user_data is the plugin’s opaque context. Return 0 on success; nonzero
signals a handled error (the host logs it; dispatch continues to other
handlers — one handler’s error does not abort the fan-out). The one
exception: when the host dispatches a lifecycle event through its
veto-aware path, returning EVENT_HANDLER_ABORT stops the fan-out and
aborts that phase (see the constants above).