docs: function execute(collector, cmd, options, callback)
  {
    collector._process = exec(cmd, options, function(err, stdout, stderr)
    {
      var cmdPrefix = ''
        , child     = collector._process
        ;
  
      // normalize
      stdout = (stdout || '').trim();
      stderr = (stderr || '').trim();
  
      // clean up finished process reference
      delete collector._process;
  
      if (err)
      {
        // clean up shell errors
        err.message = (err.message || '').trim();
        err.stdout  = stdout;
        err.stderr  = stderr;
  
        // make it uniform across node versions (and platforms as side effect)
        // looking at you node@6.3+
        if (err.cmd && (cmdPrefix = err.cmd.replace(cmd, '')) != err.cmd)
        {
          err.cmd = cmd;
          err.message = err.message.replace(cmdPrefix, '');
        }
  
        // check if process has been willingly terminated
        if (child._executioner_killRequested && err.killed)
        {
          // mark job as properly terminated
          err.terminated = true;
  
          // it happen as supposed, so output might matter
          callback(err, stdout);
          return;
        }
  
        // just an error, no output matters
        callback(err);
        return;
      }
  
      // everything is good
      callback(null, stdout);
    });
  }