A CXX file is a source code file, similar to C++, for writing applications. It can contain complete implementation of an entire application or can have partial implementation of the program that can be included in a project with other C++ files. CXX files can be opened in any text editor and popular programming IDEs such as Notepad++, Turbo C++ and Visual Studio,
CXX File Format
CXX files are stored as plain text file and contains code written in C++ syntax. CXX files are commonly found with .cpp extension as well. CXX files are considered as an alternate to .cpp used by some compilers.