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The GROUP_MEMBERSHIP structure holds information on a group membership.

 typedef struct _GROUP_MEMBERSHIP {
   unsigned long RelativeId;
   unsigned long Attributes;
 } GROUP_MEMBERSHIP,
  *PGROUP_MEMBERSHIP;

RelativeId: A RID that represents one membership value.

Attributes: Characteristics about the membership represented as a bitmask. Values are defined in section 2.2.1.10.