lb_$lookup_range Library Routine

Communications Technical Reference, Volume 1

lb_$lookup_range Library Routine

Purpose

Looks up information in a Global Location Broker (GLB) or Local Location Broker (LLB) database.

Syntax

void lb_$lookup_range (object, object_type, object_interface, location, lookup_handle)
void lb_$lookup_range (location_length, max_results, num_results, results, status)
uuid_$t *object;
uuid_$t *object_type;
uuid_$t *object_interface;
socket_$addr_t *location;
unsigned long location_length;
lb_$lookup_handle_t *lookup_handle;
unsigned long max_results;
unsigned long *num_results;
lb_$entry_t results [ ];
status_$t *status;

Description

The lb_$lookup_range routine returns database entries that contain matching object, obj_type, and obj_interface identifiers. A value of uuid_$nil in any of these input parameters acts as a wildcard and matches all values in the corresponding entry field. You can include wild cards in any combination of these parameters.

The lb_$lookup_interface routine cannot return more than the number of matching entries specified by the max_results parameter at one time. The lookup_handle parameter directs this routine to do sequential lookup calls to find all matching entries.

Notes:
The Location Broker does not prevent modification of the database between lookup calls, which can cause the locations of entries relative to a value of the lookup_handle parameter value to change. If multiple calls are made to find all matching results in the database, the returned information may skip or duplicate entries from the database.

The results of a single lookup call can possibly skip or duplicate entries. This can occur if the size of the results exceeds the size of a remote procedure call (RPC) packet (64KB).

Parameters

Input

object	Points to the Universal Unique Identifier (UUID) of the object being looked up.
object_type	Points to the UUID of the type being looked up.
object_interface	Points to the UUID of the interface being looked up.
location	Points to the location of the database to be searched. If the value of the location_length parameter is 0, the GLB database is searched. Otherwise, the LLB database at the host specified by the socket address is searched. If the LLB database is searched, the port number in the socket address is ignored, and the lookup request is sent to the LLB port.
location_length	Specifies the length, in bytes, of the socket address indicated by the location parameter. A value of 0 indicates that the GLB database is to be searched.
max_results	Specifies the maximum number of matching entries that can be returned by a single call. This should be the number of elements in the results array.

Input/Output

lookup_handle

Specifies a location in the database. On input, the value of the lookup_handle parameter indicates the location in the database where the search begins. An input value of lb_$default_lookup_handle specifies that the search starts at the beginning of the database.

On return, the lookup_handle parameter indicates the next unsearched part of the database (that is, the point at which the next search should begin). A return value of lb_$default_lookup_handle indicates that the search reached the end of the database. Any other value indicates that the search found the number of matching entries specified by the max_results parameter before it reached the end of the database.

Output

num_results	Points to the number of entries that were returned in the results parameter array.
results	Specifies the array that contains the matching GLB database entries, up to the number specified in the max_results parameter. If the array contains any entries for servers on the local network, those entries appear first.
status	Points to the completion status.

Examples

To look up information in the GLB database about the change_if interface to the proc_db2 object (which is of the proc_db type), enter:

lb_$lookup_range (&proc_db2_id, &proc_db_id, &change_if_id,
   glb, 0, &lookup_handle, 10, &num_results, results, &st);

The name glb is defined elsewhere as a null pointer. The results parameter is a 10-element array of the lb_$entry_t type.

Implementation Specifics

This Library Routine is part of Network Computing System in Network Support Facilities in Base Operating System (BOS) Runtime.

Related Information

Remote Procedure Call (RPC) Runtime Library (NCS) in AIX Version 4.3 Communications Programming Concepts.