Chapter 4 - Mappers
This chapter describes mappers, the type of Open Transport provider that lets your application map entity names to protocol addresses. You can use mapper functions to register a name, to look up a name or name pattern, or to remove
a registered name. Which functions are supported depends on the name-
registration protocol underlying the mapper provider you create. For more detailed information about how mapper functions are implemented for
the protocol you are interested in, consult the documentation provided for
that protocol.You do not have to open a mapper provider if you are interested only in registering a name or looking up an address corresponding to a name.
If you are using an endpoint that cannot be bound by name, if you want to look up a name pattern, or if you want to use other mapper functions, you need to read this chapter and learn how to create a mapper provider.
- If the protocol you are using allows you to bind an endpoint by name and you do so, the name is automatically registered on the network. This is a more efficient way to register a name on the network than to create a mapper to do it.
- If you want to obtain the address that corresponds to an entity name, you can use the endpoint function
OTResolveAddress. Using this function also saves you the trouble of opening a mapper. However, you cannot use this function to look up a name pattern; that is, the name you look up cannot include a wildcard character.
This chapter begins with a general description of mapper providers and continues with a more detailed discussion of how you use mappers asynchronously and how you use the mapper to look up names. The functions used to register names and delete names are discussed in the section "Mappers Reference," beginning on page 4-11.
Mapper providers, like all Open Transport providers, can operate synchronously or asynchronously, can block, and can acknowledge sends. For general information about Open Transport providers, see the chapter "Providers" earlier in this book.
Chapter Contents
- About Mappers
- Using Mappers
- Setting Modes of Operation for Mappers
- Specifying Name and Address Information
- Searching for Names
- Retrieving Multiple Entries From the Reply Buffer
- Retrieving Entries in Asynchronous Mode
- Mappers Reference
- Constants and Data Types
- The TRegisterRequest Structure
- The TRegisterReply Structure
- The TLookupRequest Structure
- The TLookupReply Structure
- The TLookupBuffer Structure
- Functions
- Creating Mappers
- Registering and Deleting Names
- Looking Up Names