diff --git a/lib/ulib/awk b/lib/ulib/awk
index 15bb948..63afe19 100644
--- a/lib/ulib/awk
+++ b/lib/ulib/awk
@@ -1448,8 +1448,8 @@ function printmerged(lline, rline, nocopy,        linecsv, tmplinecsv) {
   }
   linecsv = array_formatcsv(lfields)
   tmplinecsv = array_formatcsv(rfields)
-  if (tmplinecsv != "") {
-    if (linecsv != "") linecsv = linecsv ","
+  if (array_len(rfields) > 0) {
+    if (array_len(lfields) > 0) linecsv = linecsv ","
     linecsv = linecsv tmplinecsv
   }
   print linecsv