Add. set_logger function allow logging errors (crash Lua VM) in current llthread's threads.

``` Lua
local llthreads = require "llthreads"
local LOG = require"log".new(
  require "log.writer.net.zmq".new("tcp://127.0.0.1:5555")
)
llthread.set_logger(function(msg) LOG.error(msg) end)
```

1 files changed, 20 insertions, 0 deletions

diff --git a/README.md b/README.md
index c0b67bf..3721b90 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,26 @@ This is full dropin replacement for [llthreads](https://github.com/Neopallium/lu
 ##Additional
 * thread:join() method support zero timeout to check if thread alive
 * thread:join() method support arbitrary timeout on Windows platform
+* set_logger function allow logging errors (crash Lua VM) in current llthread's threads
 
 [![Bitdeli Badge](https://d2weczhvl823v0.cloudfront.net/moteus/lua-llthreads2/trend.png)](https://bitdeli.com/free "Bitdeli Badge")
 
+
+##Usage
+
+### Use custom logger
+In this example I use [lua-log](https://github.com/moteus/lua-log) library.
+``` Lua
+-- This is child thread.
+local llthreads = require "llthreads"
+-- Send logs using ZMQ
+local LOG = require"log".new(
+  require "log.writer.net.zmq".new("tcp://127.0.0.1:5555")
+)
+llthread.set_logger(function(msg) LOG.error(msg) end)
+
+...
+
+-- This error with traceback will be passed to logger
+error("SOME ERROR")
+```