update readme, add wiki link

README.md

@@ -34,8 +34,6 @@ Each lua file only load once and cache it in memory during skynet start . so if
 
 You can also use the offical lua version , edit the makefile by yourself .
 
-## Blog (in Chinese)
+## How To (in Chinese)
 
-* http://blog.codingnow.com/2012/09/the_design_of_skynet.html
-* http://blog.codingnow.com/2012/08/skynet.html
-* http://blog.codingnow.com/eo/skynet/
+* Read Wiki https://github.com/cloudwu/skynet/wiki

lualib-src/lua-socket.c

@@ -246,6 +246,7 @@ lclearbuffer(lua_State *L) {
 	while(sb->head) {
 		return_free_node(L,2,sb);
 	}
+	sb->size = 0;
 	return 0;
 }
 
@@ -264,6 +265,7 @@ lreadall(lua_State *L) {
 		return_free_node(L,2,sb);
 	}
 	luaL_pushresult(&b);
+	sb->size = 0;
 	return 1;
 }
 

service/multicastd.lua

@@ -50,8 +50,10 @@ function command.DEL(source, c)
 	channel[c] = nil
 	channel_n[c] = nil
 	channel_remote[c] = nil
-	for node in pairs(remote) do
-		skynet.send(node_address[node], "lua", "DELR", c)
+	if remote then
+		for node in pairs(remote) do
+			skynet.send(node_address[node], "lua", "DELR", c)
+		end
 	end
 	return NORET
 end

test/testmulticast2.lua

@@ -4,9 +4,13 @@ local mc = require "multicast"
 
 skynet.start(function()
 	print("remote start")
-	skynet.monitor("simplemonitor", true)
 	local console = skynet.newservice("console")
 	local channel = dc.get "MCCHANNEL"
+	if channel then
+		print("remote channel", channel)
+	else
+		print("create local channel")
+	end
 	for i=1,10 do
 		local sub = skynet.newservice("testmulticast", "sub")
 		skynet.call(sub, "lua", "init", channel)