spec.setProgressHandler(progressHandler);
                });
            } catch (Exception e) {
                /*getLogger().error("Failed command, dumping dmesg", e);
                service.execute(spec -> {
                    spec.setCommand("ssh");
                    spec.setArgs("--command", "dmesg");
                    spec.setProgressHandler(line -> {

         *
         * The function takes the current line of output from vagrant, and returns a new
         * progress line, or {@code null} if there is no update.
         */
        public void setProgressHandler(UnaryOperator<String> progressHandler) {
            this.progressHandler = progressHandler;
        }
    }

    private class ProgressOutputStream extends LoggingOutputStream {