Apple Network Setup manual Working with Entities, Listing All Entities

C H A P T E R 2

Using Network Setup

Working with Entities

Once you have a reference to the database and an area identifier for the default area, the next step is to look for appropriate entities within that area. Regardless of what you want to do to an entity, you must first obtain a reference to it. An entity reference is an opaque data structure that Network Setup uses to uniquely identify each entity within an area.

Typically there are two ways to get the entity reference for an entity within an area.

■You can list all of the entities of a particular class and type and display that list to the user. For example, you might want to list all of the TCP/IP network connection entities so that the user can choose the one to make active. The section “Listing All Entities” (page 30) explains how to do this.

■You can find the currently active entity of a particular class and type. This is useful when you want to read the current network settings. The section “Finding an Active Entity” (page 34) explains how to do this.

You can also create, duplicate, rename, and delete entities. These tasks are easy to do and are not explained in detail in this chapter. See “Network Setup Reference” (page 57) for information about OTCfgCreateEntity (page 76), OTCfgDuplicateEntity (page 78), OTCfgSetEntityName (page 81), and OTCfgDeleteEntity (page 78).

Listing All Entities

Listing 2-5 shows the routine MyGetEntitiesList, which generates a list of all of the entities within an area of the database. The routine’s database reference and area identifier parameters are obtained by opening the database, as explained in “Opening the Database for Reading” (page 25). The entityClass and entityType parameters specify the entities to list. Some common scenarios include:

■Getting all entities of a specific class and type. Set the entityClass and entityType parameters to that class and type. For example, to find all TCP/IP network connection entities, supply a class of kOTCfgClassNetworkConnection and a type of kOTCfgTypeTCPv4. See “Entity Classes and Types” (page 104) for a list of the defined classes and types.

30Working with Entities