From f0465c0d0b2517ff4809788e5ae6b47f986b32d3 Mon Sep 17 00:00:00 2001
From: Eric Chiang <eric.chiang.m@gmail.com>
Date: Thu, 22 Sep 2016 11:00:37 -0700
Subject: [PATCH] scripts/devnet: print usage if no arguments are provided

Before:

    $ sudo ./scripts/devnet
    ./scripts/devnet: line 20: $1: unbound variable

After:

    $ sudo ./scripts/devnet
    USAGE: devnet <command>
    Commands:
    	create	create bootcfg and PXE services on the bridge
    	destroy	destroy the services on the bridge
---
 scripts/devnet | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/devnet b/scripts/devnet
index 21f72a6f..d039f952 100755
--- a/scripts/devnet
+++ b/scripts/devnet
@@ -17,6 +17,10 @@ if [ "$EUID" -ne 0 ]
 fi
 
 function main {
+  if [ "$#" -ne 1 ]; then
+    usage
+    exit 2
+  fi
   case "$1" in
     "create") create;;
     "destroy") destroy;;