List...() functions
USAGE
ListLen = (short) List_Len(TopItem)
Position = (short) List_Position(TopItem, Item)
Item = (struct ListItem *) List_Pred(TopItem, NextItem)
Item = (struct ListItem *) List_Index(TopItem, Position)
TopItem = (struct ListItem *) List_Insert(TopItem, Item, Position)
TopItem = (struct ListItem *) List_Remove(TopItem, Item)
TopItem = (struct ListItem *) List_Cat(FirstList, SecondList)
FUNCTION
These are a set of general purpose list handling routines that are useful if
you are using singly linked lists where the first field in each item is a
pointer to the next item.
You can use these to manipulate gadget lists and the lists you display with
the ListInfo structure.
Some routines that alter a list return a pointer to the top item in the list.
This is because the top item get changed to a new value.
INPUTS
TopItem = Pointer to the top item in your list.
Item = Pointer to a specific item in thelist. Might be TopItem.
NextItem = Pointer to the item following the one we wish to access.
FirstList = pointer to the first item in a list that will have e second list
attached to it.
SecondList = Pointer to the first item in the second list for the
concatanation operation.
Position = Count that indicates at what position in the list Item is. A
Position of -1 can be used to indicate the end of the list.
RESULT
ListLen = the len of the requested list
Position , Item, TopItem see above