C Pre-processor - C language #ifdef, #else, #endif Pre-processor
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Learn C - C tutorial - c language #ifdef #else #endif pre-processor - C examples - C programs
C language #ifdef, #else, #endif Pre-processor
Directives
- The directives #ifdef, #else, and #endif are pre-processor directives which are used to specify which code will be compiled by the compiler based on defined macros.
![c language #ifdef #else #endif pre-processor](https://wikitechy.com/cdn/tutorials/c-programming/c-language-ifdef-else-endif-pre-processor.jpg)
Learn C - C tutorial - c language #ifdef #else #endif pre-processor - C examples - C programs
Sample Code
#include <stdio.h>
#define DEBUG 1
int main()
{
#ifdef DEBUG
printf("Debug is ON\n");
printf("wikitechy\n");
#else
printf("Debug is OFF\n");
#endif
return 0;
}
Output
Debug is ON
wikitechy