diff --git a/regress/control-subscriptions.sh b/regress/control-subscriptions.sh
index 25c732ac0..f720b0650 100644
--- a/regress/control-subscriptions.sh
+++ b/regress/control-subscriptions.sh
@@ -7,7 +7,7 @@ LANG=C.UTF-8
 export TERM LC_ALL LANG
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest -f/dev/null"
+TMUX="$TEST_TMUX -Ltest$$ -f/dev/null"
 
 TMPDIR=$(mktemp -d)
 IN="$TMPDIR/in"
diff --git a/regress/set-hook-B.sh b/regress/set-hook-B.sh
new file mode 100755
index 000000000..0d8eed372
--- /dev/null
+++ b/regress/set-hook-B.sh
@@ -0,0 +1,150 @@
+#!/bin/sh
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+LANG=C.UTF-8
+export TERM LC_ALL LANG
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+OUT=$(mktemp -d)
+TMUX_TMPDIR="$OUT"
+export TMUX_TMPDIR
+TMUX="$TEST_TMUX -Ltest-hook-B-$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	$TMUX kill-server 2>/dev/null || true
+	rm -rf "$OUT"
+	exit 1
+}
+
+cleanup()
+{
+	$TMUX kill-server 2>/dev/null || true
+	rm -rf "$OUT"
+}
+trap cleanup EXIT
+
+wait_for()
+{
+	option=$1
+	expected=$2
+	i=0
+
+	while [ $i -lt 30 ]; do
+		value=$($TMUX show -gqv "$option" 2>/dev/null || true)
+		[ "$value" = "$expected" ] && return 0
+		i=$((i + 1))
+		sleep 0.2
+	done
+	fail "expected $option to be '$expected' but got '$value'"
+}
+
+assert_unchanged()
+{
+	option=$1
+	expected=$2
+	i=0
+
+	while [ $i -lt 15 ]; do
+		value=$($TMUX show -gqv "$option" 2>/dev/null || true)
+		[ "$value" = "$expected" ] || \
+			fail "expected $option to remain '$expected' but got '$value'"
+		i=$((i + 1))
+		sleep 0.2
+	done
+}
+
+$TMUX new -d -s one || fail "new-session failed"
+
+$TMUX set -g @seen 0 || fail "set @seen failed"
+$TMUX set-hook -g -B '@session-name::#{session_name}' \
+	'set -g @seen "#{hook}:#{hook_value}"' ||
+	fail "set-hook -B failed"
+shown=$($TMUX show-hooks -g -B @session-name) ||
+	fail "show-hooks -B failed"
+[ "$shown" = '@session-name::#{session_name}' ] ||
+	fail "unexpected show-hooks -B output: $shown"
+assert_unchanged @seen 0
+
+$TMUX rename-session two || fail "rename-session two failed"
+wait_for @seen '@session-name:two'
+
+$TMUX set -g @seen-last 0 || fail "set @seen-last failed"
+$TMUX set-hook -g -B '@session-name::#{session_name}' \
+	'set -g @seen-last "#{hook_last}->#{hook_value}"' ||
+	fail "set-hook -B replacement failed"
+assert_unchanged @seen-last 0
+$TMUX rename-session one || fail "rename-session one failed"
+wait_for @seen-last 'two->one'
+
+$TMUX set-hook -gu -B @session-name || fail "set-hook -gu -B failed"
+shown=$($TMUX show-hooks -g -B @session-name) ||
+	fail "show-hooks -B after remove failed"
+[ -z "$shown" ] || fail "show-hooks -B showed removed monitor: $shown"
+last=$($TMUX show -gqv @seen-last)
+$TMUX rename-session three || fail "rename-session three failed"
+assert_unchanged @seen-last "$last"
+
+$TMUX set -gu @value || fail "unset @value failed"
+$TMUX set -g @empty-seen 0 || fail "set @empty-seen failed"
+$TMUX set-hook -g -B '@empty::#{@value}' \
+	'set -g @empty-seen "#{hook_last}->#{hook_value}"' ||
+	fail "set-hook -B empty failed"
+assert_unchanged @empty-seen 0
+$TMUX set -g @value changed || fail "set @value failed"
+wait_for @empty-seen '->changed'
+
+if $TMUX set-hook -g -B 'bad::#{session_name}' 'display-message x' \
+	>"$OUT/bad.out" 2>"$OUT/bad.err"; then
+	fail "non-@ monitor hook name was accepted"
+fi
+
+session=$($TMUX display -p '#{session_id}')
+window=$($TMUX display -p '#{window_id}')
+pane=$($TMUX display -p '#{pane_id}')
+pane_number=${pane#%}
+
+$TMUX set -gu @pane-value || fail "unset @pane-value failed"
+$TMUX set -g @pane-seen 0 || fail "set @pane-seen failed"
+$TMUX set-hook -g -B "@pane:%$pane_number:#{pane_width}" \
+	'set -g @pane-seen "#{hook_session}:#{hook_window}:#{hook_window_index}:#{hook_pane}:#{hook_value}"' ||
+	fail "set-hook -B pane selector failed"
+assert_unchanged @pane-seen 0
+$TMUX set-hook -g -B "@pane:%$pane_number:#{@pane-value}" \
+	'set -g @pane-seen "#{hook_session}:#{hook_window}:#{hook_window_index}:#{hook_pane}:#{hook_value}"' ||
+	fail "set-hook -B pane replacement failed"
+assert_unchanged @pane-seen 0
+$TMUX set -g @pane-value changed || fail "set @pane-value failed"
+wait_for @pane-seen "$session:$window:0:$pane:changed"
+
+$TMUX set -g @exact-value one || fail "set @exact-value failed"
+$TMUX set -g @exact-seen 0 || fail "set @exact-seen failed"
+$TMUX set -gw @foo 'set -g @exact-seen inherited' ||
+	fail "set global @foo failed"
+$TMUX set-hook -w -B '@foo::#{@exact-value}' ||
+	fail "set-hook -B exact scope monitor failed"
+assert_unchanged @exact-seen 0
+$TMUX set -g @exact-value two || fail "set @exact-value two failed"
+assert_unchanged @exact-seen 0
+$TMUX set-hook -w -B '@foo::#{@exact-value}' \
+	'set -g @exact-seen "#{hook_value}"' ||
+	fail "set-hook -B exact scope command failed"
+assert_unchanged @exact-seen 0
+$TMUX set -g @exact-value three || fail "set @exact-value three failed"
+wait_for @exact-seen three
+
+target_pane=$($TMUX splitw -P -F '#{pane_id}') ||
+	fail "split-window failed"
+$TMUX set -g @target-pane 0 || fail "set @target-pane failed"
+$TMUX set-hook -g -B '@target:%*:#{@target-value}' \
+	'set -g @target-pane "#{pane_id}"' ||
+	fail "set-hook -B target pane failed"
+assert_unchanged @target-pane 0
+$TMUX set -pt "$target_pane" @target-value changed ||
+	fail "set pane @target-value failed"
+wait_for @target-pane "$target_pane"
+
+exit 0