Module programming - Basic query !

[amith <amith@multitech.co.in>]

Hi all,
        Some more module related queries .

1)
i found this declaration   -     extern struct module *module_list;
(or is it a definition i'am always confused :-) ) in module.h . Now
when i include <linux/module.h> this symbol would be part of my
module . i checked "cat /proc/ksyms | grep "module_list" and
didnt find it in /proc/ksyms.My question is is it ok to have an
extern declaration if doesnt exist at all or if it isnt referenced in my 
program ?
when i insmoded my module "insmod proc1.o" there were no errors so i 
assume it is ok .
if no please let me know when it is not ok .


2)
My usecount somehow went up and i couldnt rmmod my module so i did this :

int
init_module(void)
{
   struct module *temp = THIS_MODULE;
   atomic_t zero;
   zero.counter = 0;
   while(temp) {
   if(strcmp(temp->name,"proc1")==0) /* my module was name proc1.o */
          {   
       temp->uc.usecount=zero;
           return 0;
      }
   temp = temp->next;
      }
return 0;
}

THIS_MODULE i found was #define THIS_MODULE    (&__this_module)
Now, how does this (i.e &__this_module) finally point to my modules
struct module ? How is this done ?


cheers,
Amith


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