diff --git a/tools/find-double-newline.sh b/tools/find-double-newline.sh
index c41811483c..6e7e4cb699 100755
--- a/tools/find-double-newline.sh
+++ b/tools/find-double-newline.sh
@@ -10,7 +10,7 @@ case "$1" in
                         DIR="$2"
                 fi
 
-                find $DIR -type f \( -name '*.c' -o -name '*.xml' \) -exec $0 diff \{\} \;
+                find $DIR -type f \( -name '*.[ch]' -o -name '*.xml' \) -exec $0 diff \{\} \;
                 ;;
 
         recpatch)
@@ -20,7 +20,7 @@ case "$1" in
                         DIR="$2"
                 fi
 
-                find $DIR -type f \( -name '*.c' -o -name '*.xml' \) -exec $0 patch \{\} \;
+                find $DIR -type f \( -name '*.[ch]' -o -name '*.xml' \) -exec $0 patch \{\} \;
                 ;;
 
         diff)