diff --git a/.bin/senddmesg b/.bin/senddmesg
index 245b37c..56a4d97 100755
--- a/.bin/senddmesg
+++ b/.bin/senddmesg
@@ -5,7 +5,7 @@ TO=dmesg@openbsd.org
 FROM=sdk@openbsd.org
 SUBJECT="$1"
 
-if [ -z $SUBJECT ]
+if [ -z "$SUBJECT" ]
 then
     SUBJECT="$(sysctl -n hw.version) - $(doas what /bsd | grep OpenBSD | cut -d"(" -f1 | tr -d '\t')"
 fi