rpc_ns_mgmt_inq_exp_age- returns the application's global expiration age for cached copies of name service data
void rpc_ns_mgmt_inq_exp_age( unsigned32 *expiration_age, unsigned32 *status);
- The application's global expiration age, in seconds, for cached copies of name service data.
- Returns the status code from this routine. The status code indicates whether the routine completed successfully, or if not, why not.
Possible status codes and their meanings include:
The rpc_ns_mgmt_inq_exp_age() routine returns the application's global name service expiration age.
The effect of expiration age on name service operations is implementation-dependent. For implementations that cache, the expiration age is the maximum amount of time, in seconds, that a cached copy of data from a name service attribute is considered valid by name service operations that read data from a name service. Name service routines that may be affected by expiration age are as follows:
- rpc_ns_binding_import_done() rpc_ns_binding_lookup_next() rpc_ns_entry_object_inq_next() rpc_ns_group_mbr_inq_next() rpc_ns_profile_elt_inq_next()
Implementations that cache look for cached copies of the requested data. When there is no cached copy, the operation creates one with fresh data from the name service database. When there is a cached copy, the operation compares its age with the calling application's expiration age. If the copy's age exceeds the expiration age, the operation attempts to update the cached copy with fresh data from the name service. If updating fails, the cached data remains unchanged and the requested operation fails, returning the rpc_s_name_service_unavailable status code.
Implementations that do not cache behave as if the expiration age were 0 (zero). Fresh data is always retrieved from the name service.
Every application maintains a global expiration age value. When an application begins running, the RPC run-time system specifies an implementation-dependent default global expiration age for the application. Applications may change this value by calling rpc_ns_mgmt_set_exp_age(). Applications may also set the expiration ages of individual name service handles. Whenever a name service operation is performed using a handle for which the application has not set an expiration age, the global expiration age value is used.
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