Task Pool words

Task pools provide a means of managing multiple tasks and dynamically creating and destroying them. Note that the total number of task that may exist at any one time is fixed, but the number of executing tasks may be of any number less than or equal to that at any point in time.

task-pool

The following words are in task-pool:

x-no-task-available

( – )

Exception raised if one attempts to spawn a task from a task pool and no tasks are available.

spawn-from-task-pool

( xn … x0 count xt task-pool – task )

Spawn a task from a task pool, if a task is available, or raise x-no-task-available if no tasks are available. xn through x0 are parameters to pass to the xt when executed, and count is the number of such parameters.

task-pool-free

( task-pool – count )

Get the number of free tasks in a task pool.

init-task-pool

( dict-size stack-size rstack-size count addr – )

Initialize a task pool at addr, with count tasks, each with stack-size stack size, rstack-size return stack size, and dict-size dictionary size; note that stack-size, rstack-size, and dict-size are rounded up to the nearest four bytes. These tasks are terminated initially, and are free to be spawned as needed.

task-pool-size

( count – bytes )

Get the size (excluding the tasks themselves) taken up by a task pool with count tasks; this size should be used for alloting the block of memory to be passed to init-task-pool