Users shouldn't care or know about the network's internal addressing.
Some of the application issues with NATs spring directly from this issue
(e.g. user of X-terminal setting display based on IP address instead of
DNS name).
it's not the same issue. the point of using IP addresses in DISPLAY
variables is not to make them visible to the user - it's because
using the IP address is (in a non-NATted network) far more reliable
than depending on the DNS lookup to work. the fact that doing this
makes the address more visible to the user is just a side effect;
most users don't care diddly about it one way or the other as long
as it works.
Keith
The default DISPLAY variable for an X Server on the local machine is
unix:0
This means contact the 0th display attached to the 0th X Server on the
local machine. When you make a connection to a remote machine you
cannot count on the return from gethostname() is going to have any
relationship to the name in the DNS. Not to mention that on a
multi-homed machine you need to be able to choose the IP address that
is actually accessible to the remote. So what you do is look at the
IP address on the local end of the socket that is being used to
connect to the remote system and insert that IP address into the
exported DISPLAY variable. This has of course worked for 20 years and
fails when a NAT is in the middle.
Jeffrey Altman * Sr.Software Designer * Kermit-95 for Win32 and OS/2
The Kermit Project * Columbia University
612 West 115th St #716 * New York, NY * 10025
http://www.kermit-project.org/k95.html *
kermit-support(_at_)kermit-project(_dot_)org