C/C++ Preprocessor Reference 

The C/C++ Preprocessor Reference explains the preprocessor as it is implemented in Microsoft C/C++. The preprocessor performs preliminary operations on C and C++ files before they are passed to the compiler. You can use the preprocessor to conditionally compile code, insert files, specify compile-time error messages, and apply machine-specific rules to sections of code.

In This Section

• Preprocessor Directives
  Describes directives, typically used to make source programs easy to change and easy to compile in different execution environments.

• Preprocessor Operators
  Discusses the four preprocessor-specific operators used in the context of the #define directive.

• Predefined Macros
  Discusses predefined macros as specified by ANSI and Microsoft C++.

• Pragmas
  Discusses pragmas, which offer a way for each compiler to offer machine- and operating system-specific features while retaining overall compatibility with the C and C++ languages.

Related Sections

• C++ Language Reference
  Provides reference material for the Microsoft implementation of the C++ language.

• C Language Reference
  Provides reference material for the Microsoft implementation of the C language.

• Building a C/C++ Program
  Provides links to topics discussing compiler and linker options.

• Visual C++ Libraries
  Provides links to the various libraries provided with Visual C++, including ATL, ATL Server, MFC, OLE DB, the C run-time library, and the Standard C++ Library.

• VC++ Directories, Projects and Solutions, Options Dialog Box
  Describes the user interface in Visual Studio that enables you to specify the directories that the project system will search to locate files for your C++ project.