Re: SOCKET Connect() connects but shouldn't. -- RPG400-L


On 06/02/2006, at 12:17 PM, Dave Johnson wrote:

I guess I'm not understanding why you keep mentioning the IP address.

Only that I don't believe you are connecting to the system you thinkyou are connecting to. For example, your network may be set up to useSOCKS or a proxy in which case you would really be connecting to theproxy and the proxy would forward the request and response. For SOCKSyou would normally have to configure the client to use the SOCKSserver.

That's why I suggested getpeername() because it may shed some light onwhere the system thinks you are connected.

What difference would that make?

Maybe it's not the same address on each pass due a coding defect. Thereis at least one such in your code.

When I have the socket server running on the PC, the program works. IfI stop the socket server on the PC two seconds later and then rerunthe program again, it appears to work but doesn't really. I can'timagine how the IP address would change on the same interactivesession in the space of 20 seconds unless I'm totally notunderstanding this process.

inet_addr() expects a null-terminated string to be passed in. You arepassing a character variable with no null-terminator that I could see.If storage happened to have a null on the first pass and didn't on thesecond pass this would explain why the address could change.

You don't check that inet_addr() completed successfully. You just usewhatever it returns which could be -1. This would be interpreted as anIP address of 255.255.255.255

Also RtvNetAds is returning 16 bytes from position 877. Why? It shouldbe returning 15 bytes from position 878 (equal to offset 877).

Try running the expected-failure run immediately after signing on to afresh session. Does this behave the same way?

It would be odd but maybe you're getting some latent connexion due tododgy TCP stack. Maybe the PC socket server hasn't properly closedthings?


Regards,
Simon Coulter.
--------------------------------------------------------------------
   FlyByNight Software         AS/400 Technical Specialists

   http://www.flybynight.com.au/
   Phone: +61 3 9419 0175   Mobile: +61 0411 091 400        /"\
   Fax:   +61 3 9419 0175                                   \ /
                                                             X
                 ASCII Ribbon campaign against HTML E-Mail  / \
--------------------------------------------------------------------