There is no serial data when run the examples

I follow the tutorial http://ardupilot.org/dev/docs/learning-ardupilot-the-example-sketches.html#learning-ardupilot-the-example-sketches
The examples/INS_generic can be build and upload, but the serial port does not show any data. I am facing with the below line on the terminal when i am connecting to Pixhawk,

Log Directory:
Telemetry log: mav.tlog

I have stuck on this for almost ten days.
Thanks for your help!

I had a search through the ArduPilot source code and couldnt find that text anywhere produced by the Pixhawk so my guess is that whatever serial port terminal software you are running on your PC is producing the message.

What operating system are you on and what serial port terminal are you using to receive the Pixhawk data?

EDIT In fact it looks like this is just a startup message produced by MavProxy. I know little about mavproxy. Maybe you need to analyse the mavproxy startup options?

And also how are you connecting to the Pixhawk? I think that the serial data should come via the USB cable. There is no need to connect anything but the USB which provides power and data

I use ubuntu16.10 OS, and use the USB cable to connect to Pixhawk.
I followed this tutorial http://ardupilot.org/dev/docs/learning-ardupilot-the-example-sketches.html

As it said ,I use the command ./waf build --target examples/UART_test --upload ,and it really seccess!

I use cutecom as my serial port terminal, and it does not show any data.

I also use the mavproxy command : mavproxy.py --setup --master /dev/serial/by-id/usb-3D_Robotics_PX4_FMU_v2.x_0-if00 the result shows as below

I finally solve this problem!
I change into version Copter-3.3, and everything is OK!

I’m having this exact problem…what do you mean by, “change into version Copter-3.3”?

I’m building as follows:
./waf configure --board=CubeBlack
./waf build --target examples/INS_generic --upload

This is how I build and load to my Puxhawk2, and I’m wondering what your instruction would be to change so I can fix the same problem you had above.

probably you need to add
#include <stdio.h> at the top of the example you are trying to run