Name

dced_object_read - Reads a data item of a dced service on a specific host

Synopsis

#include <dce/dced.h> void dced_object_read(
dced_binding_handle_t dced_bh,
uuid_t ∗entry_uuid,
void ∗∗data,
error_status_t ∗status);

Parameters

Input

dced_bhSpecifies the dced binding handle for a dced service on a specific host. 

entry_uuidSpecifies the UUID of the dced service’s data entry associated with the data item. 

Output

dataReturns the data read.  The data returned is one of the following structures, depending on the service:

statusReturns the status code from this routine.  This status code indicates whether the routine completed successfully or, if not, why not. 

Description

The dced_object_read() routine reads the data for a specified entry of a dced service.  When the application is done with the data, it should call the dced_objects_release() routine with a value of 1 for the count parameter. 

The valid services for which you can read data include hostdata, srvrconf, srvrexec, and keytab.  These host services each have a list of data entries maintained by dced.  The entries do not contain the actual data, but contain the data’s identity and an indicator of the location of the data item.  The hostdata service also has the dced_hostdata_read() routine to read data, and the keytab service has a series of routines that traverse over the keys in a key table.  (See the dced_keytab_initialize_cursor() routine.)  The secval and endpoint services do not have data items to read with this routine. 

Applications can also read the data for all entries of a service using one call to dced_objects_read_all(). 

Prior to reading the actual data, an application commonly obtains the entries to read using the series of cursor routines that begin with dced_entry_initialize_cursor(). 

Prior to calling the dced_object_read() routine, the application must have established a valid dced binding handle by calling either the dced_binding_create() or dced_binding_from_rpc_binding() routine. 

Examples

The following example creates a dced binding to a dced service based on a service type and host in an RPC binding handle.  The example then obtains the service’s entry list and reads the data associated with each entry. 

dced_binding_from_rpc_binding(service_type, rpc_bh, &dced_bh, &status);
dced_list_get(dced_bh, &entries, &status);
for(i=0; i<entries.count; i++) {
   dced_object_read(dced_bh, &entries.list[i].id, &data, &status);
   .
   .
   .
   dced_objects_release(dced_bh, 1, data, &status);
}
 .
 .
 .

Errors

The following describes a partial list of errors that might be returned.  Refer to the OSF DCE Problem Determination Guide for complete descriptions of all error messages. 

error_status_ok

db_s_bad_index_type

db_s_key_not_found

dce_cf_e_file_open

dce_cf_e_no_match

dce_cf_e_no_mem

dced_s_bad_binding

dced_s_need_privacy

dced_s_no_memory

dced_s_no_support

dced_s_not_found

rpc_s_binding_has_no_auth

rpc_s_invalid_binding

rpc_s_wrong_kind_of_binding

sec_acl_invalid_permission

sec_key_mgmt_e_authn_invalid

sec_key_mgmt_e_key_unavailable

sec_key_mgmt_e_unauthorized

uuid_s_bad_version

Related Information

Functions: dced_binding_create(3dce), dced_binding_from_rpc_binding(3dce), dced_hostdata_read(3dce), dced_initialize_cursor(3dce), dced_keytab_initialize_cursor(3dce), dced_objects_read_all(3dce), dced_objects_release(3dce). 

Books: OSF DCE Application Development Guide.