diff --git a/custom_bin/changeport b/custom_bin/changeport
old mode 100644
new mode 100755
index 5736503..50c030e
--- a/custom_bin/changeport
+++ b/custom_bin/changeport
@@ -18,8 +18,12 @@ subprocess() {
     return 0
 } 
 
-ret=''
-subprocess ret
+if [ ! -z "$1" ]; then
+    ret="$1"
+else
+    ret=''
+    subprocess ret
+fi
 
 export ESPPORT=$ret