title: Dockerfile windows questions about "RUN"
body: <p>I am trying to write docekerfile for windows that uses powershell scripts. The code in question is:</p>
  <pre><code>ARG BASE_PATH=c:\\TEMP
  
  WORKDIR ${BASE_PATH}
  
  ARG MINGW32_SCRIPT=install_python.ps1
  ARG MINGW32_INSTALLER=mingw-get-0.6.2-mingw32-beta-20131004-1-bin.zip
  ADD ${MINGW32_SCRIPT} ${BASE_PATH}\\${MINGW32_SCRIPT} 
  COPY ${MINGW32_INSTALLER} ${BASE_PATH}\\${MINGW32_INSTALLER}
  
  RUN powershell -command &quot;./%MINGW32_SCRIPT%&quot;
  </code></pre>
  <p>How can I use return value from %MINGW32_SCRIPT% to fail the build if the script fails?</p>
  <p>Note:</p>
  <p>I tried to set</p>
  <pre><code>SHELL [&quot;powershell&quot;, &quot;-command&quot;]
  
  ...
  
  RUN ${MINGW32_SCRIPT}
  </code></pre>
  <p>but that seems not to work? Whats wrong? It fails because:</p>
  <p>./${MINGW32_SCRIPT} : The term './${MINGW32_SCRIPT}' is not recognized as ....</p>