Errors are now displayed on attach so use control mode to test

instead.

regress/kill-session-process-exit.sh

@@ -8,13 +8,14 @@ TERM=screen
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -Ltest"
 $TMUX kill-server 2>/dev/null
+sleep 1
 
 $TMUX -f/dev/null new -d 'sleep 1000' || exit 1
 P=$($TMUX display -pt0:0.0 '#{pane_pid}')
 $TMUX -f/dev/null new -d || exit 1
 sleep 1
 $TMUX kill-session -t0:
-sleep 1
+sleep 3
 kill -0 $P 2>/dev/null && exit 1
 $TMUX kill-server 2>/dev/null