Querying the SDP Database

How to query for a remote service

A service search returns the record handles of services that are of a specified class or classes (identified by UUID numbers). If the search is for more than one UUID, then all the UUIDs must exist in a service record for it to be considered a match. See " Service Discovery Protocol Assigned Numbers " for the common UUIDs.

Service search results are returned through asynchronous callbacks to an MSdpAgentNotifier interface, which the querier must implement, as discussed later.

Basic Procedure

The steps to perform a service search are as follows:

1. Create a CSdpAgent object, supplying it with an MSdpAgentNotifier and the device address of the remote Bluetooth device.

2. Create a CSdpSearchPattern object to specify the service classes to search for. Classes can be added through CSdpSearchPattern::AddL() .

3. Set the search pattern on the agent object using CSdpAgent::SetRecordFilterL() .

4. Call CSdpAgent::NextRecordRequestL() to get search results until results are exhausted, or sufficient results have been obtained.

Querying for a service

The following code fragements may be used, in an appropriate context, to query a remote device's SDP database for Obex file transfer support (for example). The steps are given here:

1. Create agent. (Assume rcvr implements MSdpAgentNotifier and devAddr is the address of the remote device.)

            
             
            
            CSdpAgent* agent = CSdpAgent::NewLC(rcvr, devAddr);
           

2. Create a search pattern and add a service classes to it.

            
             
            
            CSdpSearchPattern* list = CSdpSearchPattern::NewL();
   list->AddL(0x1106);
           

   The UUID 0x1106 represents the OBEXFileTransfer service class.

3. Set the search pattern on the agent.

            
             
            
            agent->SetRecordFilterL(*list);
           

4. Get first search result: results in call back to rcvr .

            
             
            
            agent->NextRecordRequestL();
           

A positive match indicates a device has been found that supports OBEX file transfer. The above code may serve as a template to search for any service class for which you have the UUID value.

Where next?

The complete set of Service Discovery Agent tutorials are shown below:

• Querying the SDP database - This document

• Reading remote SDP service attributes

• Handling SDP query results

Also refer to the Bluetooth Service Discovery Agent Overview and the Bluetooth SDP Overview for additional background information.