added faqs

_data/docs.yml

@@ -15,4 +15,5 @@
   - /manual/examples
 - title: Appendices
   docs:
+  - /faq
   - /appendices/devdocs

faq/index.md

@@ -0,0 +1,6 @@
+---
+layout: default
+title: Frequently Asked Questions
+short: FAQ
+---
+ * [How can I call a script after each rsync operation?](postscript)

faq/postscript/index.md

@@ -0,0 +1,40 @@
+---
+layout: default
+title: FAQ: How can I call a script after each rsync operation?
+---
+The issue with this quite frequent request is, by itself it complicates error handling a lot. What should Lsyncd do, when the script fails that it ought to run after each rsync call? If it should recall the post script it would require a new state for each rsync event which would complicate Lsyncd code quite a bit.
+
+The easiest way to get around this, is by replacing the rsync binary Lsyncd calls by a script from you, that calls rsync and does whatever you want to do, when rsync completes. The only thing to take care is that Lsyncd communicates with rsync using stdin/out/err-pipes and thus better not interfere with these.
+
+Also take care the script properly forwards the exit code rsync returned.
+
+This is an example bash script to wrap around rsync:
+
+{% highlight shell %}
+#!/bin/bash
+/usr/bin/rsync "$@"
+result=$?
+(
+  if [ $result -eq 0 ]; then
+     echo "my commands";
+  fi
+) >/dev/null 2>/dev/null </dev/null
+
+exit $result
+{% endhighlight %}
+
+It does not do error handling for post commands. If you need this, you'll have to code them here fitting your requirements.
+
+Above script can be used as rsync wrapper replacement like this:
+
+
+{% highlight lua %}
+sync {
+    default.rsync, 
+    source = "/path/to/source", 
+    target = "targethost::targetdir", 
+    rsync = {
+        binary = "/path/to/bash/handler.sh"
+    }
+}
+{% endhighlight %}