{
{   The purpose of this request is to initiate shadowing of files.
{   Modified pages of the file to be shadowed are written to disk
{   and the segment for the file to be shadowed is transformed into
{   an ACTIVE segment to allow continuation of access to files during
{   an online dump.
{
{       MMP$INITIATE_SHADOWING (POINTER, STATUS)
{
{ POINTER: (input) This parameter specifies the process virtual
{       address assigned to the segment.
{
{ STATUS: (output) This parameter specifies the request status.
{
