Generic Pointer: Memory Type Identification

A generic pointer's encoding is described in the manual.

http://www.keil.com/support/man/docs/c51/c51_ap_genericptr.htm

Ok, thank you, but... what should I write instead of "???" in the sample below to detect the memory type of the generic pointer (function parameter)?

void mem_type_detector (char *generic_ptr)
{
   switch (???)
   {
      case 0x00:  // DATA
         //...
         break;

      case 0x01:  // XDATA
         //...
         break;
      //...
   }
}

switch (*(unsigned char*)&generic_ptr)

Oh, and your function should really be:

void mem_type_detector (void *generic_ptr)

I'd also create an enum (or at least series of #defines) for the constant values of the type tags.