best-practice on C header files with #ifndef #define #endif

Question

what is concerned best practice regarding the following \"pattern\"?

#ifndef BLAFOO_H
#define BLAFOO_H
/* ...
 * ...
 */
#endif /* BLAFOO_H */

Answer 1

It doesn't really matter as long as it's not likely to be used anywhere else. I usually go with something like BLAFOO_H_INCLUDED.