You can use wpFindUseItem to determine how an object is being used. It searches an object's in-use list for items of a specified type and returns a pointer to the USEITEM data structure that matches that specified type. The wpFindViewItem method finds USAGE_OPENVIEW items in the use list. The following figure shows the syntax of the USEITEM data structure:

typedef struct _USEITEM
{
  ULONG   type;                 /* Type of this item     */
  struct _USEITEM FAR *pNext;   /* Next item in use list */
}USEITEM;

The following sample code shows an example of how you can use the usage methods. It uses the wpFindUseItem and wpFindViewItem along with the USAGE_OPENVIEW item.

SOMAny    *Object;
PVIEWITEM pViewItem;
PUSEITEM  pUseFile;
ULONG     ulView;
// Are there any open views of this object?
if (_wpFindUseItem(Object, USAGE_OPENVIEW, NULL))
{
  // Find any views of this object
  for (pViewItem = _wpFindViewItem(Object, VIEW_ANY, NULL);
       pViewItem;
       pViewItem = _wpFindViewItem(Object, VIEW_ANY, pViewItem))
  {
    // Is a program running?
    if (pViewItem->view == OPEN_RUNNING)
    {
      ulView = (ULONG)0;

      // Find any open file use-items
      for (pUseFile = _wpFindUseItem(Object, USAGE_OPENFILE, NULL);
           pUseFile;
           pUseFile = _wpFindUseItem(Object, USAGE_OPENFILE, pUseFile))
      {
        // Does the VIEWFILE's open handle match the VIEWITEM's open handle?
        if (((PVIEWFILE)(pUseFile+1))->handle == pViewItem->handle)
        {
          // Save the VIEWFILE's menu id
          ulView = ((PVIEWFILE)(pUseFile+1))->ulMenuId;
          break;
        }
      }
    }
  }
}