return portsFile.readLines("UTF-8").get(0)
    }

    /** Returns a file that wraps around the actual command when {@code spawn == true}. */
    @Internal
    protected File getWrapperScript() {
        return new File(cwd, Os.isFamily(Os.FAMILY_WINDOWS) ? 'run.bat' : 'run')
    }

    /** Returns a file that the wrapper script writes when the command failed. */
    @Internal