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nis_ismember(3nsl) [linux man page]

nis_groups(3NSL)				       Networking Services Library Functions					  nis_groups(3NSL)

NAME
nis_groups, nis_ismember, nis_addmember, nis_removemember, nis_creategroup, nis_destroygroup, nis_verifygroup, nis_print_group_entry - NIS+ group manipulation functions SYNOPSIS
cc [ flag ... ] file ... -lnsl [ library ... ] #include <rpcsvc/nis.h> bool_t nis_ismember(nis_name principal, nis_name group); nis_error nis_addmember(nis_name member, nis_name group); nis_error nis_removemember(nis_name member, nis_name group); nis_error nis_creategroup(nis_name group, uint_t flags); nis_error nis_destroygroup(nis_name group); void nis_print_group_entry(nis_name group); nis_error nis_verifygroup(nis_name group); DESCRIPTION
These functions manipulate NIS+ groups. They are used by NIS+ clients and servers, and are the interfaces to the group authorization object. The names of NIS+ groups are syntactically similar to names of NIS+ objects but they occupy a separate namespace. A group named "a.b.c.d." is represented by a NIS+ group object named "a.groups_dir.b.c.d."; the functions described here all expect the name of the group, not the name of the corresponding group object. There are three types of group members: o An explicit member is just a NIS+ principal-name, for example "wickedwitch.west.oz." o An implicit ("domain") member, written "*.west.oz.", means that all principals in the given domain belong to this member. No other forms of wildcarding are allowed: "wickedwitch.*.oz." is invalid, as is "wickedwitch.west.*.". Note that principals in subdomains of the given domain are not included. o A recursive ("group") member, written "@cowards.oz.", refers to another group. All principals that belong to that group are considered to belong here. Any member may be made negative by prefixing it with a minus sign ('-'). A group may thus contain explicit, implicit, recursive, negative explicit, negative implicit, and negative recursive members. A principal is considered to belong to a group if it belongs to at least one non-negative group member of the group and belongs to no nega- tive group members. The nis_ismember() function returns TRUE if it can establish that principal belongs to group; otherwise it returns FALSE. The nis_addmember() and nis_removemember() functions add or remove a member. They do not check whether the member is valid. The user must have read and modify rights for the group in question. The nis_creategroup() and nis_destroygroup() functions create and destroy group objects. The user must have create or destroy rights, respectively, for the groups_dir directory in the appropriate domain. The parameter flags to nis_creategroup() is currently unused and should be set to zero. The nis_print_group_entry() function lists a group's members on the standard output. The nis_verifygroup() function returns NIS_SUCCESS if the given group exists, otherwise it returns an error code. These functions only accept fully-qualified NIS+ names. A group is represented by a NIS+ object with a variant part that is defined in the group_obj structure. See nis_objects(3NSL). It con- tains the following fields: uint_t gr_flags; /* Interpretation Flags (currently unused) */ struct { uint_t gr_members_len; nis_name *gr_members_val; } gr_members; /* Array of members */ NIS+ servers and clients maintain a local cache of expanded groups to enhance their performance when checking for group membership. Should the membership of a group change, servers and clients with that group cached will not see the change until either the group cache has expired or it is explicitly flushed. A server's cache may be flushed programmatically by calling the nis_servstate() function with tag TAG_GCACHE and a value of 1. There are currently no known methods for nis_ismember(), nis_print_group_entry(), and nis_verifygroup() to get their answers from only the master server. EXAMPLES
Example 1: Simple Memberships Given a group sadsouls.oz. with members tinman.oz., lion.oz., and scarecrow.oz., the function call bool_var = nis_ismember("lion.oz.", "sadsouls.oz."); will return 1 (TRUE) and the function call bool_var = nis_ismember("toto.oz.", "sadsouls.oz."); will return 0 (FALSE). Example 2: Implicit Memberships Given a group baddies.oz., with members wickedwitch.west.oz. and *.monkeys.west.oz., the function call bool_var = nis_ismem- ber("hogan.monkeys.west.oz.", "baddies.oz."); will return 1 (TRUE) because any principal from the monkeys.west.oz. domain belongs to the implicit group *.monkeys.west.oz., but the function call bool_var = nis_ismember("hogan.big.monkeys.west.oz.", "baddies.oz."); will return 0 (FALSE). Example 3: Recursive Memberships Given a group goodandbad.oz., with members toto.kansas, @sadsouls.oz., and @baddies.oz., and the groups sadsouls.oz. and baddies.oz. defined above, the function call bool_var = nis_ismember("wickedwitch.west.oz.", "goodandbad.oz."); will return 1 (TRUE), because wickedwitch.west.oz. is a member of the baddies.oz. group which is recursively included in the goodand- bad.oz. group. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
nisgrpadm(1), nis_objects(3NSL), attributes(5) NOTES
NIS+ might not be supported in future releases of the SolarisTM Operating Environment. Tools to aid the migration from NIS+ to LDAP are available in the Solaris 9 operating environment. For more information, visit http://www.sun.com/directory/nisplus/transition.html. SunOS 5.10 18 Dec 2001 nis_groups(3NSL)

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