diff --git a/acme.sh b/acme.sh
index d5d9f313..043308e9 100755
--- a/acme.sh
+++ b/acme.sh
@@ -1131,7 +1131,7 @@ _ss() {
       elif netstat -help 2>&1 | grep -- '-P protocol' >/dev/null; then
         #for solaris
         netstat -an -P tcp | grep "\.$_port " | grep "LISTEN"
-      elif netstat -help 2>&1 | grep "\-p" > /dev/null; then
+      elif netstat -help 2>&1 | grep "\-p" >/dev/null; then
         #for full linux
         netstat -ntpl | grep ":$_port "
       else