Himanshu Pandey wrote:

But as we discussed, the server does NOT keep track of statistics for each module return codes.

Yes... I've said that repeatedly. Perhaps you could repeat it some more, to be sure that I understand how the server works?

The very first thing that I did was finding out the basic module structure in freeradius, if I am not wrong this is the basic module structure used:

Yes.

Now I added an unsigned long array in this structure in which module return code act as an index. Please see the snippet below:

That's not a good idea. For one, the module return codes are already in a typedef. Just use that one. There's no reason to create a new one. And "unsigned long" isn't used anywhere else in the server. Just use "uint64_t".

Please advice me that how should I update this my unsigned long rtcode[RLM_RETCODE_COUNT] array with each module return code.

Use C code to increment the array entry. See modcall.c, call_modsingle(). Alan DeKok.