USECXX_FLAG
The USECXX_FLAG macro enables you to go to a subdirectory that has all C files and compile them with the C++ compiler instead of the C compiler. (You might want to do this if you have decided to switch to C++.)
Instead of manually changing all of your file name suffixes from .c to.cpp, you can specify the following flag:
USECXX_FLAG=1
This switch directs the compiler to use the C++ compiler instead of the C compiler to compile the specified subdirectory.
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Build date: 5/3/2011