Port the last example

examples/231-Cfg-OutputStreams.cpp

@@ -6,10 +6,12 @@
 // there is no important difference between having `std::cerr` buffered
 // or unbuffered.
 
-#define CATCH_CONFIG_NOSTDOUT
-#define CATCH_CONFIG_MAIN
+#include <catch2/catch_default_main.hpp>
+
 #include <catch2/catch.hpp>
 
+#include <sstream>
+#include <cstdio>
 
 class out_buff : public std::stringbuf {
     std::FILE* m_stream;

examples/CMakeLists.txt

@@ -17,8 +17,11 @@ add_executable( 020-MultiFile
   020-TestCase-2.cpp
 )
 
-# TODO: How to handle differently configured libraries?
-#       Needed in 231-Cfg-OutputStreams
+add_executable(231-Cfg_OutputStreams
+    231-Cfg-OutputStreams.cpp
+)
+StampOutLibrary(231-Cfg_OutputStreams)
+target_compile_definitions(Catch2_231-Cfg_OutputStreams PUBLIC CATCH_CONFIG_NOSTDOUT)
 
 # These examples use the standard separate compilation
 set( SOURCES_IDIOMATIC_EXAMPLES