libxml2 convert a node and all it's containt to a string

[Goliath2k]

I would like to convert a node and all it's content and children to a string.for example I have this node\[code\]<node i="a"> <child1>azerty</child1> <child2>qwerty</child2></node>\[/code\]I would like to have function to translate to a string "str1"the content of the string will be like this:\[code\]<node i="a"> <child1>azerty</child1> <child2>qwerty</child2></node>\[/code\]