Clarify which build instructions to look at for C++ vs C at the top of the README.

[SeppeG]

Hi PointOne

While trying out the Septentrio example, I found out that the CMakelist is not quite right. If you follow the instructions, not all examples are built.

I did get it working with the Raspberry Pi and the Septentrio mosaicHAT, and am impressed with the accuracy!

[adamshapiro0]

Hi Seppe,

Do you know which examples were not built for you? I just ran the C++ cmake instructions and I believe all of the examples were built correctly.

Were you able to move or change one of the CMakeLists.txt file in a way that helped?

[SeppeG]

According to the readme, i should make a build directory in polaris/c and run cmake .. and make, when I do that only 3 examples are build:

[ 42%] Built target polaris_client
[ 71%] Built target connection_retry
[100%] Built target simple_polaris_client

to build the septentrio examples you have to cd to polaris/examples and run cmake .. and make but i dont see it in the readme.

[adamshapiro0]

Ah, I believe you may have followed the instructions in the "Polaris C Client" section for building the C language library in polaris/c/ (https://github.com/PointOneNav/polaris#polaris-c-client). That builds only the C library and the C examples (polaris/c/examples/).

The top-level directory (polaris/) contains the C++ library. The files in polaris/examples/ are all C++ applications. The instructions to build them are in the "Polaris C++ Client" section here: https://github.com/PointOneNav/polaris#polaris-c-client-1 (ignore the fact that it says "c-client-1" in the URL, Github markdown ignores the ++ in the section title).

Let me know if that works a little better.

[SeppeG]

I got it working, but it wasn't that clear at first 🙃

[adamshapiro0]

Gotcha. We'll see if we can make that a little more clear up front in the README.

Just to be 100% clear though, you should be able to just do the following to build the C++ library and examples:

cd polaris
mkdir build
cd build
cmake ..
make

You shouldn't really need to build inside polaris/examples/ yourself ever.

[SeppeG]

cd polaris
mkdir build
cd build
cmake ..
make

This gives me:

seppe:~/Documents$ git clone [email protected]:PointOneNav/polaris.git
Cloning into 'polaris'...
seppe:~/Documents$ cd polaris/
seppe:~/Documents/polaris(master)$ mkdir build
seppe:~/Documents/polaris(master)$ cd build
seppe:~/Documents/polaris/build(master)$ cmake ..
-- The C compiler identification is GNU 9.4.0
-- The CXX compiler identification is GNU 9.4.0
-- Check for working C compiler: /usr/lib/ccache/cc
-- Check for working C compiler: /usr/lib/ccache/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/lib/ccache/c++
-- Check for working CXX compiler: /usr/lib/ccache/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
CMake Error at cmake/FindGflags.cmake:121 (message):
  Failed to find gflags - Could not find gflags include directory, set
  GFLAGS_INCLUDE_DIR to directory containing gflags/gflags.h
Call Stack (most recent call first):
  cmake/FindGflags.cmake:464 (gflags_report_not_found)
  CMakeLists.txt:28 (find_package)


-- Configuring incomplete, errors occurred!
See also "/home/seppe/Documents/polaris/build/CMakeFiles/CMakeOutput.log".

[adamshapiro0]

Did you install the requirements in the C++ instructions (https://github.com/PointOneNav/polaris#cmake-1)?

sudo apt install libssl-dev libgflags-dev libgoogle-glog-dev libboost-all-dev

Note that this is different than the C library, which only requires libssl-dev.

[SeppeG]

Oh yes, my mistake