Key Value Pair in C Language

I am new to C programming and I am trying to create a key value structure as in Perl Programming. I saw one solution like :-

struct key_value
{
   int key;
   char* value;
};

struct key_value kv;

kv.key = 1;
kv.value = "foo";

But I don't know how to access these values from this structure. Can someone enlight on this ?