Function sioul_alarm_decide 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn sioul_alarm_decide(
    key: *const c_char,
) -> *mut c_char

At a dose’s time: what to say (health::alarm_decide). Blocks up to half a minute (the sync app given time to bring the others’ marks): never on Android’s main thread.

Safety

key is null, or a zero-terminated text valid for the call.