Enhancements to PR open-telemetry#86 Add minimal tracer example (open…

…-telemetry#94)

CMakeLists.txt

@@ -23,9 +23,9 @@ include(CTest)
 find_package(Threads)
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
-  # Options for Visual C++ compiler:
-  # /Zc:__cplusplus - report an updated value for recent C++ language standards.
-  # Without this option MSVC returns the value of __cplusplus="199711L"
+  # Options for Visual C++ compiler: /Zc:__cplusplus - report an updated value
+  # for recent C++ language standards. Without this option MSVC returns the
+  # value of __cplusplus="199711L"
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /Zc:__cplusplus")
 endif()
 

examples/simple/README.md

@@ -0,0 +1,10 @@
+
+# Simple Trace Example
+
+In this example, the application in `main.cc` initializes and registers a tracer
+provider from the [OpenTelemetry SDK](https://github.com/open-telemetry/opentelemetry-cpp).
+The application then calls a `foo_library` which has been instrumented using
+the [OpenTelemetry API](https://github.com/open-telemetry/opentelemetry-cpp/tree/master/api).
+Resulting telemetry is directed to stdout through a custom exporter.
+
+See [CONTRIBUTING.md](../../CONTRIBUTING.md) for instructions on building and running the example.

examples/simple/main.cc

@@ -15,14 +15,14 @@ void initTracer()
   auto processor = std::shared_ptr<sdktrace::SpanProcessor>(
       new sdktrace::SimpleSpanProcessor(std::move(exporter)));
   auto provider = nostd::shared_ptr<trace::TracerProvider>(new sdktrace::TracerProvider(processor));
+  // Set the global trace provider
   trace::Provider::SetTracerProvider(provider);
 }
 }  // namespace
 
 int main()
 {
-  // Removing this line will leave OT initialized with the default noop
-  // tracer, thus being effectively deactivated.
+  // Removing this line will leave the default noop TracerProvider in place.
   initTracer();
 
   foo_library();