I'm trying to find out my DNS server address by reading it from resolv.h's _res struct. According to man 3 resolver the setup code should be.
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
extern struct state _res;
and then I just read out whatever I need. My problem is that trying to compile this I get
resolver.c:5:21: error: conflicting types for '__res_state'
extern struct state _res;
^
/usr/include/resolv.h:251:16: note: expanded from macro '_res'
#define _res (*__res_state())
^
/usr/include/resolv.h:249:28: note: previous declaration is here
extern struct __res_state *__res_state(void) __attribute__ ((__const__));
^
1 error generated.
by clang.
What am I doing wrong?
You shouldn't declare _res yourself - resolv.h includes the right declaration (despite what the man page implies).