Inserts a new element into the list, using the given comparison function to determine its position.
the data for the new element
the function to compare elements in the list. It should return a number > 0 if the first parameter comes after the second parameter in the sort order.
data to pass to comparison function
the new start of the GSList
2.10
Inserts a new element into the list, using the given comparison function to determine its position.