diff --git a/.ci/license-header.sh b/.ci/license-header.sh
index 587a552233..0cbfaa789a 100755
--- a/.ci/license-header.sh
+++ b/.ci/license-header.sh
@@ -47,8 +47,8 @@ check_header() {
     COMMENT_TYPE="$1"
     FILE="$2"
 
-    HEADER_LINE1=$(printf '%s\n' "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
-    HEADER_LINE2=$(printf '%s\n' "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
+    HEADER_LINE1=$(echo "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
+    HEADER_LINE2=$(echo "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
 
     FOUND=0
     while IFS= read -r line || [ -n "$line" ]; do
@@ -121,9 +121,8 @@ for TYPE in "SRC" "OTHER"; do
     echo "  '$DESC' files is:"
     echo
     echo "=== BEGIN ==="
-    printf '%s\n%s\n' \
-        "$(printf '%s\n' "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")" \
-        "$(printf '%s\n' "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")"
+    echo "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g"
+    echo "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g"
     echo "===  END  ==="
 done
 
@@ -157,28 +156,33 @@ if [ "$FIX" = "true" ]; then
                 ;;
         esac
 
-        LINE1=$(printf '%s\n' "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
-        LINE2=$(printf '%s\n' "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
+        LINE1=$(echo "$HEADER_LINE1_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
+        LINE2=$(echo "$HEADER_LINE2_TEMPLATE" | sed "s|{COMMENT_TEMPLATE}|$COMMENT_TYPE|g")
 
         TMP="$TMP_DIR/$BASENAME.tmp"
         UPDATED=0
 
         cp -p $file $TMP
-        printf '' > $TMP
+        echo "" > $TMP
 
         while IFS= read -r line || [ -n "$line" ]; do
             if [ "$UPDATED" -eq 0 ] && echo "$line" | grep "$COPYRIGHT_OWNER" >/dev/null 2>&1; then
-                printf '%s\n%s\n' "$LINE1" "$LINE2" >> "$TMP"
+                {
+                    echo "$LINE1"
+                    echo "$LINE2"
+                } >> "$TMP"
                 IFS= read -r _ || true
                 UPDATED=1
             else
-                printf '%s\n' "$line" >> "$TMP"
+                echo "$line" >> "$TMP"
             fi
         done < "$file"
 
         if [ "$UPDATED" -eq 0 ]; then
             {
-                printf '%s\n%s\n\n' "$LINE1" "$LINE2"
+                echo "$LINE1"
+                echo "$LINE2"
+                echo
                 cat "$TMP"
             } > "$file"
         else