diff --git a/test/run-test.sh b/test/run-test.sh
index 69302ae..a46e9a7 100644
--- a/test/run-test.sh
+++ b/test/run-test.sh
@@ -155,9 +155,9 @@ dotest "Keep mtime of the font directory"
 prep
 cp "$FONT1" "$FONTDIR"
 touch -d @0 "$FONTDIR"
-stat "$FONTDIR" | grep Modify > out1
+stat -c '%y' "$FONTDIR" > out1
 $FCCACHE "$FONTDIR"
-stat "$FONTDIR" | grep Modify > out2
+stat -c '%y' "$FONTDIR" > out2
 if cmp out1 out2 > /dev/null ; then : ; else
     echo "*** Test failed: $TEST"
     echo "mtime was modified"