2011-11-10
It's lot of usage same as #ifdef
Like #if defined(...)
When using #if defined(...)
we can used logic AND/OR for preprocessing.
Sample 1:
#ifdef ABC
// do something
#elif DEF
// do something
#else
// do something else
#endif
Sample 1 above can be simply recoding as:
#if defined(ABC) || defined(DEF)
//do something
#else
// do something else
#endif