merging in the --lua-exec feature for ncat.

ncat/scripts/conditional.lua

@@ -0,0 +1,33 @@
+--This is another --lua-exec demo. It displays a menu to a user, waits for her
+--input and makes a decision according to what the user entered. All happens
+--in an infinite loop.
+
+while true do
+
+    print("Here's a menu for you: ")
+    print("1. Repeat the menu.")
+    print("0. Exit.")
+
+    io.write("Please enter your choice: ")
+    io.flush(io.stdout)
+    i = io.read()
+
+    --WARNING! Without this line, the script will go into an infinite loop
+    --that keeps consuming system resources when the connection gets broken.
+    --Ncat's subprocesses are NOT killed in this case!
+    if i == nil then
+        break
+    end
+
+    print("You wrote: ",i,".")
+
+    if i == "0" then
+        break
+    elseif i == "1" then
+        print("As you wish.")
+    else
+        print("No idea what you meant. Please try again.")
+    end
+
+    print() --print a newline
+end