stdout</a>, <a href="Core/index.html#type-stderr">Core.stderr</a>)</span> <a href="Core/Cmd/index.html#type-t">Core.Cmd.t</a></span> <span class="arrow">&#45;&gt;</span></span>
  <span>string list</span> * <span>string list</span></span></code></div><div class="spec-doc"><p>Same as <a href="#val-lines_joined"><code>lines_joined</code></a> but reads stdout and stderr as a separate strings streams, returning a pair of string lists wrapped in the ouput type. This function uses asynchronous I/O internally, so t