Do not reuse sockets so much to avoid problems with slow server shutdown.

regress/conf-syntax.sh

@@ -4,10 +4,13 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
-$TMUX kill-server 2>/dev/null
+TMUX=
+n=0
+trap '[ -n "$TMUX" ] && $TMUX kill-server 2>/dev/null' 0 1 15
 
 for i in conf/*.conf; do
+	n=$((n + 1))
+	TMUX="$TEST_TMUX -LtestA$$-$n -f/dev/null"
 	$TMUX -f/dev/null start \; source -n $i || exit 1
 done