The routine gEnqSegGroup() returns the range of segment numbers defined for segment group ngrp. A segment group is defined by calling gDefineSegGroup() and removed by calling gRemoveSegGroup(). ngrp should lie within the range defined by a call to gDefineGroupRange(). If ngrp is out of range, segmin and segmax are returned set to -1.
If the specified segment group does not exist, segmin and segmax are returned set to zero. Otherwise, segmin and segmax return the range of segment numbers defined for the segment group.