Hi Divya, > pasting "version" and "." does not give a valid preprocessing token. That is correct. "version." is not a valid preprocessing token. It is two tokens, "version" and ".". Preprocessor pasting REQUIRES that the resulting token is a single valid token. In the case you are working with, you probably want this, which relies on string literal concatenation: #define NAME_STRING "lib" stringify(TARGET) ".so" HTH, --Eljay
