Converting [NSNetservice addresses] to ip address string

mjdth picture mjdth · Feb 24, 2010 · Viewed 8.4k times · Source

This question was already asked here: NSNetservice IP address

and here: iPhone: Bonjour NSNetService IP address and port

I've used both of those to get where I'm at now. My problem is the following method I have doesn't quite work:

- (NSString *)getStringFromAddressData:(NSData *)dataIn {
    struct sockaddr_in  *socketAddress = nil;
    NSString            *ipString = nil;

    socketAddress = (struct sockaddr_in *)[dataIn bytes];
    ipString = [NSString stringWithFormat: @"%s",
                inet_ntoa(socketAddress->sin_addr)];  ///problem here
    return ipString;
}

This gives a build error saying both "Dereferencing pointer to incomplete type" and "Implicit declaration of function 'inet_ntoa'" on the same line.

I've checked and I don't think I'm missing some type of framework to get inet_ntoa to work. Any idea what I'm doing wrong? thanks.

Answer

nall picture nall · Feb 24, 2010

If you're getting implicit declaration of inet_ntoa, you probably need

 #include <arpa/inet.h>

(You can man inet_ntoa to get this info and read more about that function)