diff -ur v3/sock_ut.py v4/sock_ut.py
--- v3/sock_ut.py	2021-06-24 21:26:04.000000000 +0900
+++ v4/sock_ut.py	2021-06-28 19:46:14.000000000 +0900
@@ -48,6 +48,10 @@
 	bt = recv_bt( sc )
 	return bt.decode( 'utf-8' )
 
+def recv_str_all( sc ):
+	bt = recv_bt_all( sc )
+	return bt.decode( 'utf-8' )
+
 def pipe_loop( sc_from, sc_to ):
 	while True:
 		bt = recv_bt( sc_from )
@@ -181,7 +185,7 @@
 		return None
 	return ss
 
-def accept_inner( ss ):
+def accept_recv_ping( ss ):
 	s = recv_str( ss )
 	if not s:
 		return None
@@ -193,6 +197,20 @@
 	if d.get( 'id' ) == 'ping':
 		return 'ping'
 
+	return ( s, d )
+
+def accept_recv( ss ):
+	r = None
+	while True:
+		r = accept_recv_ping( ss )
+		if r != 'ping':
+			break
+	return r  # None or ( s, d )
+
+def accept_conn( r ):
+	if not r:
+		return None
+	( s, d ) = r
 	port = int( d.get( 'port' ) )
 	cs = port_conn( port )
 	if not send_str( cs, s ):
@@ -205,13 +223,8 @@
 	return cs
 
 def accept( ss ):
-	cs = None
-	while True:
-		cs = accept_inner( ss )
-		if cs != 'ping':
-			break
-		#dbg.out( 'accept ping' )
-	return cs
+	r = accept_recv( ss )
+	return accept_conn( r )
 
 def srv_loop( port, name, th_func ):
 	ss = server( port, name )
@@ -223,6 +236,7 @@
 			break
 		th = thr.th_new( th_func, ( cs, ) )
 		thr.ths.start( th )
+	ss.close()
 
 def srv_func_new( cb ):