NAME
        AttachCxObj -- attach a commodity object to the end of an existing
                       list of objects. (V36)

   SYNOPSIS
        AttachCxObj(headObj,co);
                    A0      A1

        VOID AttachCxObj(CxObj *,cxobj *);

   FUNCTION
        Adds 'co' to the list of objects pointed to by 'headObj'. The
        new object is added at the end of the list.

   INPUTS
        headObj - pointer to a list of objects. If this value is NULL, then
                  the entire tree of objects pointed to by 'co' is deleted
                  and becomes invalid.
        co - the object to add to the list (may be NULL)

   RESULTS
        If 'co' is NULL, this function will record that fact in the
        internal accumulated error of 'headObj'. This error record
        can be retrieved using cxobjerror() and cleared using
        clearcxobjerror().

   BUGS
        Until V38, passing a NULL 'headObj' parameter would cause low-memory
        access and unpredictable results.

   SEE ALSO
        cxobjerror(), clearcxobjerror()