check for empty args to sessions -c

git-svn-id: file:///home/svn/framework3/trunk@8616 4d416f70-5f16-0410-b530-b9f4589650da

lib/msf/ui/console/command_dispatcher/core.rb

@@ -1083,10 +1083,12 @@ class Core
 				when "-q"
 					quiet = true
 
+				# Run a command on all sessions
 				when "-c"
 					method = 'cmd'
+					if (val)
 						cmds << val
-
+					end
 
 				when "-v"
 					verbose = true
@@ -1111,6 +1113,7 @@ class Core
 					method = 'detach'
 					sid = val
 
+				# Run a script on all meterpreter sessions
 				when "-s"
 					method = 'scriptall'
 					script = val
@@ -1129,6 +1132,7 @@ class Core
 		case method
 
 			when 'cmd'
+				if (cmds.length > 0)
 					cmds.each do |cmd|
 						framework.sessions.each_sorted do |s|
 							session = framework.sessions.get(s)
@@ -1156,6 +1160,9 @@ class Core
 							# commands on), so don't bother.
 						end
 					end
+				else
+					print_error("No command specified!")
+				end
 
 			when 'kill'
 				if ((session = framework.sessions.get(sid)))