By default, _bind() attempts to retain an IPv6 socket when a
bind timeout is requested. On systems with IPv6 disabled, the
IPv4 socket is closed and no IPv6 socket can be created, leaving
the port-holding daemon without any sockets to retain.
Default to AF_INET so the daemon can keep an IPv4 socket open
for the requested timeout on IPv4-only systems.
This fixes test_command_line_interface_no_portserver_bind_timeout
when IPv6 is disabled.
--- ../src/portpicker.py	2026-10-19 01:01:43.827309260 +0300
+++ ../src/portpicker.py	2026-10-19 01:01:59.174394319 +0300
@@ -117,7 +117,7 @@
 
 
 def _bind(port, socket_type, socket_proto, return_socket=None,
-          return_family=socket.AF_INET6):
+          return_family=socket.AF_INET):
     """Internal implementation of bind.
 
     Args: