diff --git a/lib/ulib/conf b/lib/ulib/conf
index 98c123c..d733fc1 100644
--- a/lib/ulib/conf
+++ b/lib/ulib/conf
@@ -399,9 +399,9 @@ function write_unseen(write_section,                      wrote_section) {
         splitvar "$param" name value
         script="$script
 in_section && \$0 ~ /^[ $TAB]*((##*|;;*)[ $TAB]*)?$name[ $TAB]*=/ {
-  \$0 = gensub(/^[ $TAB]*(##*|;;*)[ $TAB]*($name[ $TAB]*=)/, \"\\\\2\", \"\")
+  \$0 = gensub(/^[ $TAB]*(##*|;;*)[ $TAB]*($name[ $TAB]*=)/, \"\\\\2\", 1)
   if (hasvalues[$i]) {
-    \$0 = gensub(/^([ $TAB]*$name[ $TAB]*=[ $TAB]*).*\$/, \"\\\\1\" values[$i], \"\")
+    \$0 = gensub(/^([ $TAB]*$name[ $TAB]*=[ $TAB]*).*\$/, \"\\\\1\" values[$i], 1)
   }
   seen[$i] = 1
   modified = 0
diff --git a/lib/ulib/udir b/lib/ulib/udir
index 7e57927..e8cc465 100644
--- a/lib/ulib/udir
+++ b/lib/ulib/udir
@@ -169,7 +169,7 @@ function write_unseen() {
         name="${param%%=*}"
         script="$script
 \$0 ~ /^[ $TAB]*(##*[ $TAB]*)?$name[ $TAB]*=/ {
-  \$0 = gensub(/^([ $TAB]*##*)?([ $TAB]*$name[ $TAB]*=[ $TAB]*).*\$/, \"\\\\2\" values[$i], \"\")
+  \$0 = gensub(/^([ $TAB]*##*)?([ $TAB]*$name[ $TAB]*=[ $TAB]*).*\$/, \"\\\\2\" values[$i], 1)
   seen[$i] = 1
 }"
         let i=$i+1