Add documentation and examples for new features.

examples/lua/expects.lua

@@ -0,0 +1,21 @@
+--
+-- example of intaction with AT modem.
+--
+tio.write("AT\r")
+local matches, all = tio.expect("OK", 1000)
+if matches == nil then
+    tio.echo("no response 1\r\n")
+    os.exit(0)
+end
+msleep(200)
+tio.read(1000, tio.C.NOWAIT)
+tio.write("ATFANTASYCMD\r")
+local idx, matches, all = tio.expects({"OK", "ERROR", "BUSY"}, 1000)
+if idx == nil then
+    tio.echo("no response 2\r\n")
+    os.exit(0)
+end
+
+-- this display 2, ERROR
+print(idx, matches[1])
+os.exit(0)