diff --git a/scripts/shutdown.in b/scripts/shutdown.in
index af3ea2b3..23e5e31d 100644
--- a/scripts/shutdown.in
+++ b/scripts/shutdown.in
@@ -1,14 +1,31 @@
 #!/bin/sh
 
-shutdown_arg=
+do_halt=false
 while getopts :akrhPHfFnct: opt; do
 	case "$opt" in
 		a) ;;
 		k) ;;
-		r) shutdown_arg=--reboot ;;
-		h) shutdown_arg=--halt ;;
-		P) shutdown_arg=--poweroff ;;
-		H) shutdown_arg=--halt ;;
+		r)
+			shutdown_arg=--reboot
+			;;
+		h)
+			do_halt=true
+			shutdown_arg=--poweroff
+			;;
+		P)
+			if ! ${do_halt}; then
+				printf "%s\n" "The -P flag requires the -h flag" >&2
+				exit 1
+			fi
+			shutdown_arg=--poweroff
+			;;
+		H)
+			if ! ${do_halt}; then
+				printf "%s\n" "The -H flag requires the -h flag" >&2
+				exit 1
+			fi
+			shutdown_arg=--halt
+			;;
 		f) ;;
 		F) ;;
 		n) ;;
@@ -25,5 +42,5 @@ if [ -z "${shutdown_arg}" ]; then
 	shutdown_arg=--single
 fi
 
-echo @SBINDIR@/openrc-shutdown ${shutdown_arg} "$@"
+printf "%s %s\n" "@SBINDIR@/openrc-shutdown ${shutdown_arg}" "$@"
 exec @SBINDIR@/openrc-shutdown ${shutdown_arg} "$@"