span></code></div><div class="spec-doc"><p>Execute a command in, where a handle to the created process will be availbe as the sole input parameter of the function <code>f</code>. When <code>f</code> exits, we close any &quot;dangling&quot; file descriptors and wait for the process to exit, finally returning the output value of <code>f</code> wrapped in the output type.</p></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-exec_joined"><a href="#val-exec_joined" class="anchor"></a><c