Debug TRACE() with variadic arguments

Define :

#ifdef DEBUG
#define TRACE(...) printf("DBG MESSAGE: " __VA_ARGS__)
#else
#define TRACE(...)
#endif

and then in program, you can use something like :

TRACE("my_array[%d]=%x\n", i , arr_val);

All the argument from TRACE() will be taken and substitued in the place of __VA_ARGS__, which will make printf to work well and print this message, with sentence DBG MESSAGE: in the begining.