topic Re: getpeername() return 0 but with IP address "0.0.0.0" in Operating System - HP-UX

getpeername() return 0 but with IP address "0.0.0.0"

Fei Rao — Wed, 05 Jul 2006 00:51:05 GMT

Hi all,

The server is listening on a specified port. When a connection request comes, the server accepts the request and then fork() a child. Then the server call getpeername() and getsockname() to get the client's and server's addresses. Unfortunately both two calls succeed and return addresses "0.0.0.0" and ports "0".

I looked up the manual and search through google, but didn't found any solutions. Do you have any ideas about this problem?

HP-UX B.11.23 9000/800 on PA-RISC

Fei

Re: getpeername() return 0 but with IP address "0.0.0.0"

Arunvijai_4 — Wed, 05 Jul 2006 00:54:59 GMT

Hi Fei,

Check for IPv6 is enabled on your server ?

# ifconfig will show it.

-Arun

Re: getpeername() return 0 but with IP address "0.0.0.0"

Fei Rao — Wed, 05 Jul 2006 01:20:23 GMT

No. Just IPv4.

Here's the source code fragment:

struct sockaddr_in peerAddr, servAddr;
int addrlen = sizeof (sockaddr_in);

if (-1 == (getpeername(sockFd, (struct sockaddr *)&peerAddr, &addrlen)))
exitError("getpeername()");

addrlen = sizeof (sockaddr_in);
if (-1 == (getsockname(sockFd, (struct sockaddr *)&servAddr, &addrlen)))
exitError("getsockname()");

cout << "Peer IP: " << inet_ntoa(peerAddr.sin_addr) << " PORT: "<< ntohs(peerAddr.sin_port) << endl;

cout << "Serv IP: " << inet_ntoa(servAddr.sin_addr) << " PORT: " << ntohs(servAddr.sin_port) << endl;

Here's the output:
Peer IP: 0.0.0.0 PORT: 0
Serv IP: 0.0.0.0 PORT: 0

Re: getpeername() return 0 but with IP address "0.0.0.0"

Torsten. — Wed, 05 Jul 2006 01:47:11 GMT

Many many years ago for me, but I guess to remember I used inet_ntoa(peerAddr.sin_addr.s_addr).
I'm not sure, because I didn't write any C stuff for years.

Re: getpeername() return 0 but with IP address "0.0.0.0"

Fei Rao — Wed, 05 Jul 2006 03:01:04 GMT

Actually, the whole structure peerAddr and servAddr are filled with '\0' as if I use memset() to set all bits to 0.

Re: getpeername() return 0 but with IP address "0.0.0.0"

rick jones — Wed, 05 Jul 2006 19:32:03 GMT

A couple things - accept() will also return the remote addressing information, so you can eliminate the per-connection getpeername() call :)

You might consider doing an memset to something other than "0" on the sockaddr so you can see if the calls are setting them to zero or simply not setting them at all.

Also, a tusc trace of the calls might be a good idea. Make it a verbose one.