Used for inserting a PDE element into the content.
Values:
| IG_PDE_BEFORE_FIRST | ((LONG) -1) | Specifies position before the first element. Usually used to insert first content element. |
| IG_PDE_AFTER_LAST | (IG_PDF_FIXED_MAX - 1) | Specifies the last element position. Usually used to insert last content element. |