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RE: Info on "Can't open display"


> -----Original Message-----
> From: Christopher Landrieu [mailto:landrieu@hotmail.com]
> 
> 
> >From: "Robert Collins" <robert.collins@itdomain.com.au>
 
> > > to try.  Do you have any recommendations?
> >
> >Uh yeah, try to establish answers to my fact finding 
> questions suggested
> >below.
> 
> Sorry, I meant any suggestions for other xclients 
> (non-cygwin/xfree86) that 
> I could test with.  I don't know many other free xclient apps 
> for windows.
 
Unless you have access to Exceed or something like that, no suggestions
sorry. 
 
> >Have you examined this or attempted to confirm your guess? I 
> asked the
> >question _because_ there are multiple answers.
> 
> I've done my share of client/server socket programming and, 
> in general, the 
> following model is used in the most architectures:
> 
> I haven't yet looked at the socket calls in TeraTermSSH but 
> you can see that 
> it is generally what is happening by playing with netstat.  
> It will show you 
> sshd listening to port 6010 on the remote host and you can 
> see TeraTermSSH's 
> connection from localhost random-port to localhost port 6000. 
>  It is this 
> local connection that should be equivalent to the 
> cygwin/xfree86 xterm 
> connecting to localhost port 6000.
 
A better tool to play with is
http://www.sysinternals.com/ntw2k/freeware/tdimon.shtml TDIMon, which
will let you see the actual calls being made.

> >... You are wrong about "all tcp/ip client programs unbound". TCP/IP
> >client can ask for a random port on a random interface (a)
> 
> 
> >or a specific
> >port on a random interface (still a - I wasn't worried about the
> >partocular port)
> 
> ... huh? How would you do that?

I'm not sure... check the ssh client source code. It does something
similar.
 
> >or a specific port on a specific interface (one of b or c).
> 
> ... using socket()...bind(), which is what server apps do.

for outbound connections? I didn't think bind() was appropriate for
that. Well live and learn().
 
> >Chris, your guesssing is not helping debug the problem. Binding to a
> >specific port on all interfaces != being "unbound" where you 
> bind to a
> >port, and no specific interface. (Binding to all interfaces 
> you need to
> >call bind() multiple times oince for each interface).
> 
> Actually, this is untrue.  If you specify INADDR_ANY in the 
> bind call, all 
> local interfaces are bound to one socket at the specified port.

Ah. Ok I'll cede that - I know TCP/IP much better than socket
programming.
 
Rob


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