Conditional Compilation In C: #ifdef #else #endif

https://technotip.com/8575/conditional-compilation-in-c-ifdef-else-endif/

In this video tutorial lets learn about preprocessor command or directives like #ifdef, #else and #endif. These directives are used for conditional compilation.

When To Use #ifdef

1. When we want the compiler to skip certain part of the source code: For this we could even use multi-line comment, but if we already had multi-line comments in the code, we can’t enclose the source code and multi-line comments with another multi-line comment. Nesting of multi-line comments are not allowed in C programming language. So instead of commenting the code we could make use of #ifdef directive.

2. To write portable code: For example, we could write code both for iOS and non-iOS devices. Using #ifdef we could check the device OS and based on that deliver specific set of codes. For this we can use #ifdef

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C Programming: Beginner To Advance To Expert https://technotip.com/6086/c-programming-beginner-to-advance-to-expert/ ... https://www.youtube.com/watch?v=J0nWQRqb3Fc