imap.rs

// get `IDLE` handle
match session.idle() {
    Err(error) => {
        println!("Failed to send command: IDLE");
        println!("IMAP server may not support IDLE command.");
        println!("Error: {}", error);
        std::process::exit(126);
    }
    Ok(idle) => {
        println!("Waiting for Ctrl-C...");
        while running.load(Ordering::SeqCst) {
            idle.wait_keepalive();
            // ^ -- Moved value being used here
        }
    }
};