Ok, I updated the test to compile better!

#include <sys/socket.h>
#include <netdb.h>

int main()
{
#ifdef NI_WITHSCOPEID
  struct sockaddr ss;
  int sslen;
  int rc;
  char hbuf[NI_MAXHOST];
  int fd = socket(AF_INET, SOCK_STREAM, 0);
  if(fd < 0)
    return 4;

  rc = getsockname(fd, (struct sockaddr *)&ss, &sslen);
  if(rc)
    return 1;

  rc = getnameinfo((struct sockaddr *)&ss, sslen, hbuf, sizeof(hbuf),
                     NULL, 0,
                     NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID);
  if(rc)
    return 2;

  return 0; /* all is fine, use NI_WITHSCOPEID */
#else
  return 3; /* don't use NI_WITHSCOPEID, we don't have it! */
#endif
}

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     Daniel Stenberg -- http://curl.haxx.se -- http://daniel.haxx.se
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