[Dev-C++] UDP Client Socket - Retrieve Local Ip Address

[Rafael M. <so...@gm...>]

Hi List


I have a client udp socket connection and wish to retrieve the client ip
address. I will print now the code structure and further information's will
come below.


SOCKET sock;

SOCKADDR_IN sins;

int sinsize=sizeof(sins);

WSADATA wsa;

WSAStartup(MAKEWORD(2,0),&wsa);

sins.sin_family=AF_INET;

sins.sin_addr.s_addr=inet_addr(ip);

sins.sin_port=htons(port);

sock=socket(AF_INET,SOCK_DGRAM,0);

 struct sockaddr_in stLclAddr;

int addrLen = sizeof(struct sockaddr_in);

int rVal = getsockname(sock,(struct sockaddr FAR *)&stLclAddr,&addrLen);

//int rVal = getsockname(sock,(sockaddr *)&stLclAddr,&addrLen);

char szIP[MAX_PATH] = "\0";

sprintf(szIP,"%s",inet_ntoa(stLclAddr.sin_addr));

WriteLog(_T(szIP));//writelog just dump the value to a file or somewhere
else

rVal = getpeername(sock,(struct sockaddr FAR *)&stLclAddr,&addrLen);

//rVal = getpeername(sock,(sockaddr *)&stLclAddr,&addrLen);

sprintf(szIP,"%s",inet_ntoa(stLclAddr.sin_addr));

WriteLog(_T(szIP));

When i run the follow code, the output sin_addr is always 204.204.204.204, I
don't know why. I cant bind the socket because i like the sysop api give-me
the in port (to recvfrom), and i just don't know witch interface on the
client machine have Internet connection (and don't like to search. let the
sysop do their jobs alone). After know that ip and port, i need to sniff
this interface(that job is already done, and need the ip input information
to watch the inbound packets and pick, from the packet header, my outside
ip:port. with that, I can have a listener on the client and set up ip and
port in the server sending a command by UPD).


Thanks in advance.

-- 
Regards
Rafael Menezes