Method
GLibTreeupper_bound
since: 2.68
Description
Gets the upper bound node corresponding to the given key,
or NULL
if the tree is empty or all the nodes in the tree
have keys that are lower than or equal to the searched key.
The upper bound is the first node that has its key strictly greater than the searched key.
Available since: 2.68
Parameters
key

Type:
gconstpointer
The key to calculate the upper bound for.
The argument can be NULL
.The data is owned by the caller of the function.
Return value
Type: GTreeNode
The tree node corresponding to the
upper bound, or NULL
if the tree is empty or has only keys
lower than or equal to the searched key.
The data is owned by the instance. 
The return value can be NULL . 