Services

A service provides a set of FIDL protocols over a channel.

Instances

Multiple named instances of a service can be hosted by a single component. If no instance name is provided, the default instance name default is used.

A component can also access multiple instances in its incoming namespace. These are presented in the incoming namespace as subdirectories of the service.

For example, the Launcher service with instance default would be accessible at the path /svc/fuchsia.sys.Launcher/default.

Protocols

A service is a grouping of named FIDL protocols. Logically-related protocols can be aggregated into a service and routed as a single unit.

An example of a FIDL service definition (defined in fuchsia.network):

service Provider {
    fuchsia.net.NameLookup name_lookup;
    fuchsia.posix.socket.Provider socket_provider;
}

Each protocol has a name and is accessible as a subdirectory of the service instance. For example, the socket_provider protocol of the fuchsia.network.Provider service instance default is accessible at the path /svc/fuchsia.network.Provider/default/socket_provider.

Routing

Services are routed to other Components through service capabilities.