getaddrinfo-no_inet6.c

#define _GNU_SOURCE
#include <dlfcn.h>
#include <netdb.h>
#include <string.h>

typedef int (*getaddrinfo_t)(const char *node, const char *service,
                const struct addrinfo *hints,
                struct addrinfo **res);

int getaddrinfo(const char *node, const char *service,
                const struct addrinfo *hints,
                struct addrinfo **res)
{
  struct addrinfo new_hints;
  memcpy(&new_hints, hints, sizeof(struct addrinfo));
  new_hints.ai_family = AF_INET;

  getaddrinfo_t gai;
  gai = (getaddrinfo_t)dlsym(RTLD_NEXT, "getaddrinfo");
  return gai(node, service, &new_hints, res);
}