title: executing shell command in docker composer gives me error
body: <p>I'm trying to execute shell command in docker-compose.yml. Code is:</p>
  <pre class="lang-yaml prettyprint-override"><code>    command: bash -c mkdir /opt/wa/usr/install_templates
  </code></pre>
  <p>When I do:</p>
  <pre class="lang-sh prettyprint-override"><code>    sudo docker-compose up  serviceA
  </code></pre>
  <p>it gives me :</p>
  <pre><code>    serviceA     | mkdir: missing operand
  </code></pre>