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$ScheduledTask

returns within a scheduled task the ScheduledTaskObject or CloudObject for the task.

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$ScheduledTask

$ScheduledTask is being phased out in favor of $CurrentTask, which was introduced experimentally in Version 11.2.

$ScheduledTask

returns within a scheduled task the ScheduledTaskObject or CloudObject for the task.

Details

  • If it is evaluated not within a scheduled task, $ScheduledTask gives None.
  • $ScheduledTask is used to refer to the task within a task evaluation, e.g. to learn the parameters or stop the task.

Examples

Basic Examples  (8)

Print the running scheduled task object:

Wolfram Language code: RunScheduledTask[Print[$ScheduledTask]]

Print its time specification:

Wolfram Language code: RunScheduledTask[Print[$ScheduledTask[[3]]]]
Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];

Remove the scheduled task automatically when it is not needed:

Wolfram Language code: RunScheduledTask[x = DateString[]];
Wolfram Language code: ScheduledTasks[]
Wolfram Language code: Dynamic[x]
Wolfram Language code: RunScheduledTask[x = Graphics[{Red, Disk[]}];RemoveScheduledTask[$ScheduledTask], 2];
Wolfram Language code: ScheduledTasks[]
Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];

Create a task with random wait periods:

Wolfram Language code: time := RandomInteger[{1, 3}]
Wolfram Language code: fun[t_] := Print["Waiting ", t, " seconds."]
Wolfram Language code: RunScheduledTask[With[{t = time}, ResetScheduledTask[$ScheduledTask, {t}];fun[t];StartScheduledTask[$ScheduledTask]], {1}];
Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];

Create a task that restarts evaluation as soon as it finishes:

Wolfram Language code: fun := With[{t = RandomInteger[{1, 3}]}, Print["Waiting ", t, " seconds."];Pause[t]]
Wolfram Language code: RunScheduledTask[fun;StartScheduledTask[$ScheduledTask], {1}];
Wolfram Language code: RemoveScheduledTask[ScheduledTasks[]];

Create a task that runs only once and removes itself after finishing:

Wolfram Language code: RunScheduledTask[Print[RandomReal[]];RemoveScheduledTask[$ScheduledTask], 0];
Wolfram Language code: ScheduledTasks[]

Create a task that removes itself once a condition is met:

Wolfram Language code: RunScheduledTask[With[{x = RandomReal[]}, Print[x];If[x > 0.6, RemoveScheduledTask[$ScheduledTask]]], 1];

Create a task that removes itself when an external variable is changed:

Wolfram Language code: x = 0;RunScheduledTask[Print[RandomReal[]];If[x ≥ 1, RemoveScheduledTask[$ScheduledTask]], 1];

Cause the task to be stopped and removed:

Wolfram Language code: x = 1

Synchronize scheduled tasks using an auxiliary task:

Wolfram Language code: n = 1;Dynamic[FlipView[{Graphics[{Red, Disk[]}], Graphics[{Green, Disk[]}]}, n]]
Wolfram Language code: x1 = CreateScheduledTask[StartScheduledTask[x3];RemoveScheduledTask[$ScheduledTask], {0.3}]; x2 = CreateScheduledTask[n = 1, 1]; x3 = CreateScheduledTask[n = 2, 1];
Wolfram Language code: ScheduledTasks[]
Wolfram Language code: StartScheduledTask[{x1, x2}];

The auxiliary task x1 was removed:

Wolfram Language code: ScheduledTasks[]

Stop all scheduled tasks:

Wolfram Language code: StopScheduledTask[ScheduledTasks[]];
Wolfram Research (2010), $ScheduledTask, Wolfram Language function, https://reference.wolfram.com/language/ref/$ScheduledTask.html (updated 2014).

Text

Wolfram Research (2010), $ScheduledTask, Wolfram Language function, https://reference.wolfram.com/language/ref/$ScheduledTask.html (updated 2014).

CMS

Wolfram Language. 2010. "$ScheduledTask." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2014. https://reference.wolfram.com/language/ref/$ScheduledTask.html.

APA

Wolfram Language. (2010). $ScheduledTask. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/$ScheduledTask.html

BibTeX

@misc{reference.wolfram_2026_$scheduledtask, author="Wolfram Research", title="{$ScheduledTask}", year="2014", howpublished="\url{https://reference.wolfram.com/language/ref/$ScheduledTask.html}", note=[Accessed: 15-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_$scheduledtask, organization={Wolfram Research}, title={$ScheduledTask}, year={2014}, url={https://reference.wolfram.com/language/ref/$ScheduledTask.html}, note=[Accessed: 15-June-2026]}