rem: struct sr_module* find_module(void* f, int *i)
add: struct sr_module* find_module(void* f, cmd_export_t  **c)
context: struct sr_module* find_module(void* f, int *i){	struct sr_module* t;	int r;	for (t=modules;t;t=t->next){		for(r=0;r<t->exports->cmd_no;r++) 			if (f==(void*)t->exports->cmd_pointers[r]) {				if (i) *i=r;				return t;			}	}	return 0;}