If you start X manually, you can use
<code>
startx -- -nolisten tcp
</code>
Another possibility is to use a firewall rule like
<code>
iptables -I INPUT -p tcp --dport 6000 -j REJECT
</code>
(Don't know if you should guard against udp as well)
How can I close X's port listening without having to save or restart each time?
What is the command?
If you start X manually, you can use
<code>
startx -- -nolisten tcp
</code>
Another possibility is to use a firewall rule like
<code>
iptables -I INPUT -p tcp --dport 6000 -j REJECT
</code>
(Don't know if you should guard against udp as well)

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