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MBR_CHECK_MEMBERSHIP(3)  BSD Library Functions Manual  MBR_CHECK_MEMBERSHIP(3)

NAME
     mbr_check_membership -- check whether a user is a member of a group

SYNOPSIS
     #include <membership.h>

     int
     mbr_check_membership(uuid_t user, uuid_t group, int *ismember);

DESCRIPTION
     mbr_check_membership() tests if a given user is a member of a group, individually or as a member of a
     nested group.  ismember is set to 1 if the user is a member of the group, and 0 otherwise.

     Users may belong to any number of grouos.  mbr_check_membership() should be always be used to check
     group membership, rather than calling getgroups(2), and checking the returned list of gids.  The
     setgroups(2) and getgroups(2) routines are limited to a fixed number of gids, and so may not include
     all of a user's groups.

     There are two special cases.  If the two uuids are equal, then ismember is set to 1.  If the group uuid
     is equal to the reserved "everyone" uuid (ABCDEFAB-CDEF-ABCD-EFAB-CDEF0000000C), then ismember will be
     set to 1 for any valid user.

     Group membership information is managed by the DirectoryService(8) daemon.

RETURN VALUES
     mbr_check_membership() returns 0 on success.  It returns EIO if it is unable to communicate with the
     DirectoryService(8) daemon.  ENOENT is returned if user cannot be found.

     Note that mbr_check_membership() does not test whether group exists or not.  Querying membership for a
     nonexistent group will result in ismember being to 0 and a return value of 0.

SEE ALSO
     setgroups(2), getgroups(2), mbr_uid_to_uuid(3), DirectoryService(8)

Mac OS X                       February 3, 2005                       Mac OS X