Re: is_callable(environment)?

[stt@houdini.camb.inmet.com (Tucker Taft)]

Tom Moran (tmoran@bix.com) wrote:

: ... but I wonder
: if I'm just very lucky, or if most compilers take the allowance of
: C.7.1(21) and allow 'caller to return a task_id of the environment
: task, and if is_callable on the environment task becomes false when it
: reaches the end of the main program and before its dependent tasks
: have terminated and library level controlled objects have finalized.

The environment task is a task, so 'Caller, 
Ada.Task_Identification.Current_Task, etc., all need to work on it.

There is also nothing that disallows Is_Callable(env-task-id), so
calling it should be "safe."  However, it is pretty easy to
imagine that the mechanism for waiting for library-level tasks
follows a different path in the run-time system than that used
when exiting an "explicit" task body, so it seems possible that
Is_Callable(env-task) might remain true indefinitely (or perhaps false
indefinitely).  Clearly, you will need to test this out on
each Ada run-time you intend to use.

--
-Tucker Taft   stt@inmet.com   http://www.inmet.com/~stt/
Intermetrics, Inc.  Burlington, MA  USA