The Be Book - System Overview - The Application Kit
The BRoster
object represents a service that keeps a roster of all
applications currently running. It can provide information about any of
those applications, activate one of them, add another application to the
roster by launching it, or get information about an application to help
you decide whether to launch it.
There's just one roster and it's shared by all applications. When an
application starts up, a
BRoster
object is constructed and assigned to a
global variable, be_roster.
You always access the roster through this
variable; you never have to instantiate a
BRoster
in application code.
The BRoster
identifies applications in three ways:
By entry_ref references to the executable files where they reside.
By their signatures. The signature is a unique identifier for the
application assigned as a file-system attribute or resource at compile
time or by the
BApplication
constructor at run time.
At run time, by their team_ids. A team is a group of threads sharing an address space; every application is a team.
If an application is launched more than once, the roster will include one entry for each instance of the application that's running. These instances will have the same signature, but different team identifiers.
