title: how to redirect stdin and stdout using boost.process
body: <p>i am trying to redirect both stdin and stdout of a child process.
  want to fill the stdin of the process with binary data from buffers and read that,(but for now i only need to know how much is written to stdout)</p>
  
  <pre><code>namespace  bp = boost::process;
  bp::opstream in;
  bp::ipstream out;
  
  bp::child c(Cmd.c_str(), bp::std_out &gt; out, bp::std_in &lt; in);
  
  in.write((char*)buffer,bufferSize);
  integer_type totalRead = 0;
  char a[10240];
  while (out.read(a,10240))  totalRead += out.gcount();
  c.terminate();
  </code></pre>
  
  <p>write looks to be successful but program got stuck in reading-while loop,
  process(both child and parent) remains idle during this </p>