I have been testing retrieving Initial values of the Attributes and it
seems that the documentation and the actual set values do not match.

  ns3::YansWifiPhy::EnergyDetectionThreshold -  INIT: -140  The energy
of a received signal should be higher than this threshold (dbm) to
allow the PHY layer to detect the signal.

The retrieved values is -140, but the documented values is "Initial
value: -96"
The rest seems to be ok, besides that it does not print all values.

#include "ns3/core-module.h"
#include "ns3/common-module.h"
#include "ns3/node-module.h"
#include "ns3/helper-module.h"
#include "ns3/mobility-module.h"
#include "ns3/contrib-module.h"
#include "ns3/wifi-module.h"
#include "ns3/athstats-helper.h"

#include <iostream>

using namespace ns3;
using namespace std;

int main (int argc, char *argv[])
{

  // enable rts cts all the time.
  Config::SetDefault
("ns3::WifiRemoteStationManager::RtsCtsThreshold", StringValue ("0"));
  // disable fragmentation
  Config::SetDefault
("ns3::WifiRemoteStationManager::FragmentationThreshold", StringValue
("2200"));

  WifiHelper wifi = WifiHelper::Default ();
  MobilityHelper mobility;
  NodeContainer stas;
  NodeContainer ap;

  NetDeviceContainer staDevs;
  PacketSocketHelper packetSocket;

  stas.Create (2);
  ap.Create (1);

  // give packet socket powers to nodes.
  packetSocket.Install (stas);
  packetSocket.Install (ap);

  NqosWifiMacHelper wifiMac = NqosWifiMacHelper::Default ();
  YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default ();
  YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default
();
  wifiPhy.SetChannel (wifiChannel.Create ());
  Ssid ssid = Ssid ("wifi-default");
  wifi.SetRemoteStationManager ("ns3::ArfWifiManager");
  // setup stas.
  wifiMac.SetType ("ns3::NqstaWifiMac",
               "Ssid", SsidValue (ssid),
               "ActiveProbing", BooleanValue (false));
  staDevs = wifi.Install (wifiPhy, wifiMac, stas);
  // setup ap.
  wifiMac.SetType ("ns3::NqapWifiMac", "Ssid", SsidValue (ssid),
               "BeaconGeneration", BooleanValue (true),
               "BeaconInterval", TimeValue (Seconds (2.5)));
  wifi.Install (wifiPhy, wifiMac, ap);

  // mobility.
  mobility.Install (stas);
  mobility.Install (ap);

  PacketSocketAddress socket;
  socket.SetSingleDevice(staDevs.Get (0)->GetIfIndex ());
  socket.SetPhysicalAddress (staDevs.Get (1)->GetAddress ());
  socket.SetProtocol (1);

  OnOffHelper onoff ("ns3::PacketSocketFactory", Address (socket));
  onoff.SetAttribute ("OnTime", RandomVariableValue (ConstantVariable
(42)));
  onoff.SetAttribute ("OffTime", RandomVariableValue (ConstantVariable
(0)));

  ApplicationContainer apps = onoff.Install (stas.Get (0));
  apps.Start (Seconds (0.5));
  apps.Stop (Seconds (0.6);

  Simulator::Stop (Seconds (1.0));

  TypeId tid = YansWifiPhy::GetTypeId();
  cout << endl << "Attributes for Sender:" << endl;
  uint32_t tidn = tid.GetAttributeN();

  /**
   * A bit tricy to get initial value
   * tid.GetAttributeInitialValue(tidcount) returns Ptr< const
AttributeValue >
   * To get string we need checker
   * ->SerializeToString(tid.GetAttributeChecker(tidcount))
   * Don't understand why its so complicated....
   */
  for (uint32_t tidcount = 0; tidcount < tidn; tidcount++) {
    cout << "  " << tid.GetAttributeFullName(tidcount) << " - " <<
        " INIT: " << tid.GetAttributeInitialValue(tidcount)-
>SerializeToString(tid.GetAttributeChecker(tidcount))<< "  "<<

        tid.GetAttributeHelp(tidcount) << endl;
  }

  //Docs needs to be checked what associated object has traces
  cout << endl << "Trace Sources for WifiPhy:" << endl;
  TypeId tid1 = WifiPhy::GetTypeId();
  uint32_t tidn1 = tid1.GetTraceSourceN();
  for (uint32_t tidcount = 0; tidcount < tidn1; tidcount++) {
    cout << "  " << tid1.GetTraceSourceName(tidcount) << " - " <<
      tid1.GetTraceSourceHelp(tidcount) << endl;
  }
  cout << endl;

  Simulator::Run ();

  Simulator::Destroy ();

  return 0;