What are the differences between C and C++ ?
Many people believe that C++ is a superset of C, and even few books happen to say so. But C++ is different from C in many ways, and it is in fact an
incomplete superset of C. There are certain
features in C which are not in C++ and in some cases, valid code constructs in C may to fail to compile in C++, and in few other instances, the C code is executes differently when compiled with C++ compiler.
Here is an excellent article by By David R. Tribble∞ describing all the incompatible and differences between C and C++. Its very helpful article for those who code in both C and C++ languages.
References
Incompatibilities Between
ISO C and ISO C++∞
Comeau C99 FAQ∞