List of Preprocessor Directives

This page lists and briefly describes preprocessor directives available. To get more information on any item listed here, go to the reference page for that item.

Preprocessor Directives
Name Action
# Null directive specifying that no action be performed.
#define Defines a preprocessor macro.
#elif Conditionally includes source text if the previous #if, #ifdef, #ifndef, or #elif test fails.
#else Conditionally includes source text if the previous #if, #ifdef, #ifndef, or #elif test fails.
#endif Ends conditional text.
#error Defines text for a compile-time error message.
#if Conditionally includes or suppresses portions of source code, depending on the result of a constant expression.
#ifdef Conditionally includes source text if a macro name is defined.
#ifndef Conditionally includes source text if a macro name is not defined.
#include Inserts text from another source file.
#line Supplies a line number for compiler messages.
#pragma Specifies implementation-defined instructions to the compiler.
#undef Removes a preprocessor macro definition.

 



Preprocessor Directives
Preprocessing Operations
Preprocessor Macros
Conditional Compilation Directives