Bind client-side UDP sockets.

caproto/curio/client.py

@@ -238,6 +238,9 @@ def __init__(self):
 
         # UDP socket broadcasting to CA servers
         self.udp_sock = ca.bcast_socket(socket)
+        # Must bind or getsocketname() will raise on Windows.
+        # See https://github.com/caproto/caproto/issues/514.
+        self.udp_sock.bind(('', 0))
         self.broadcaster.our_address = safe_getsockname(self.udp_sock)
         self.registered = False  # refers to RepeaterRegisterRequest
         self.loop_ready_event = curio.Event()

caproto/sync/client.py

@@ -326,6 +326,9 @@ def read(pv_name, *, data_type=None, timeout=1, priority=0, notify=True,
         # caproto-repeater that will continue running after it exits.
         spawn_repeater()
     udp_sock = ca.bcast_socket()
+    # Must bind or getsocketname() will raise on Windows.
+    # See https://github.com/caproto/caproto/issues/514.
+    udp_sock.bind(('', 0))
     try:
         udp_sock.settimeout(timeout)
         chan = make_channel(pv_name, udp_sock, priority, timeout)
@@ -461,6 +464,9 @@ def block(*subscriptions, duration=None, timeout=1, force_int_enums=False,
         loggers[sub.pv_name] = logging.LoggerAdapter(logging.getLogger('caproto.ch'),
                                                      {'pv': sub.pv_name})
     udp_sock = ca.bcast_socket()
+    # Must bind or getsocketname() will raise on Windows.
+    # See https://github.com/caproto/caproto/issues/514.
+    udp_sock.bind(('', 0))
     try:
         udp_sock.settimeout(timeout)
         channels = {}
@@ -651,6 +657,9 @@ def write(pv_name, data, *, notify=False, data_type=None, metadata=None,
         spawn_repeater()
 
     udp_sock = ca.bcast_socket()
+    # Must bind or getsocketname() will raise on Windows.
+    # See https://github.com/caproto/caproto/issues/514.
+    udp_sock.bind(('', 0))
     try:
         udp_sock.settimeout(timeout)
         chan = make_channel(pv_name, udp_sock, priority, timeout)
@@ -734,6 +743,9 @@ def read_write_read(pv_name, data, *, notify=False,
         spawn_repeater()
 
     udp_sock = ca.bcast_socket()
+    # Must bind or getsocketname() will raise on Windows.
+    # See https://github.com/caproto/caproto/issues/514.
+    udp_sock.bind(('', 0))
     try:
         udp_sock.settimeout(timeout)
         chan = make_channel(pv_name, udp_sock, priority, timeout)

caproto/threading/client.py

@@ -317,6 +317,9 @@ def __init__(self, *, registration_retry_time=10.0):
         self.ca_server_port = self.environ['EPICS_CA_SERVER_PORT']
 
         self.udp_sock = ca.bcast_socket()
+        # Must bind or getsocketname() will raise on Windows.
+        # See https://github.com/caproto/caproto/issues/514.
+        self.udp_sock.bind(('', 0))
 
         self._search_lock = threading.RLock()
         self._retry_unanswered_searches_thread = None

caproto/trio/client.py

@@ -327,6 +327,9 @@ async def register(self):
 
     async def _broadcaster_recv_loop(self, task_status):
         self.udp_sock = ca.bcast_socket(socket_module=socket)
+        # Must bind or getsocketname() will raise on Windows.
+        # See https://github.com/caproto/caproto/issues/514.
+        self.udp_sock.bind(('', 0))
         self.broadcaster.our_address = safe_getsockname(self.udp_sock)
         command = self.broadcaster.register('127.0.0.1')
         await self.send(ca.EPICS_CA2_PORT, command)