updated walkthrough doc

docs/walkthrough.md

@@ -3,7 +3,7 @@ Walkthrough
 
 In this document we'll run through a simple example which should demonstrate the concept of the ZeroTier SDK. For this tutorial you'll need two devices (or at least the ability to run a VM or something like [Docker](https://www.docker.com/)). We will demonstrate a simple TCP server application intercepted on linux. This is only one of *many* ways the SDK can be used, but it'll at least convey the core concept how how the intercept works.
 
-### On your first device:
+#### On your first device:
  - Download ZeroTier at [zerotier.com](https://www.zerotier.com/product-one.shtml)
  - Install it on a device/computer
  - Create an account and new virtual network at [my.zerotier.com](https://my.zerotier.com/)
@@ -13,25 +13,25 @@ In this document we'll run through a simple example which should demonstrate the
 
 
 
-### On your second device:
+#### On your second device:
 
-#### Build the SDK
+##### Build the SDK
 ```
 make linux SDK_PICOTCP=1 SDK_IPV4=1 SDK_DEBUG=1; make -s check; ls -lG build
 ```
 
-#### Build test apps
+##### Build test apps
 
 ```
 make tests
 ```
 
-#### Start the SDK service in the background
+##### Start the SDK service in the background
 ```
 ./zerotier-cli -U -p8000 /netpath &
 ```
 
-#### Set environment variables 
+##### Set environment variables 
 ```
 export ZT_NC_NETWORK=/netpath/nc_XXXXXXXXXXXXXXXX
 export LD_PRELOAD=./libztintercept.so
@@ -39,14 +39,14 @@ export LD_PRELOAD=./libztintercept.so
 
 Where `netpath` can be any path you'd like the client's keys and configuration to be stored and `XXXXXXXXXXXXXXXX` is the 16-digit network ID.
 
-#### Start your app
+##### Start your app
 ```
 ./build/tests/linux.tcpserver4.out 8001
 ```
 
-Now, on your first device, `./build/tests/linux.tcpclient4.out <ip> 8001`
+Now, on your first device, `./build/tests/linux.tcpclient4.out <ip> 8001` where `<ip>` is the ip address that you assigned to your first device.
 
-Now, you'll note that your new TCP server is automatically intercepted and available at on port 8001.
+Now, you'll note that your new TCP server is automatically intercepted and available at on port 8001. The `tcpclient4` sample app running on the device with a normal instance of ZeroTier running will be able to connect directly to your intercepted `tcpserver4` app on the second machine running the SDK.
 ***