# Processing Exception

**URL:** <https://discourse.processing.org/t/processing-exception/47566>\
**Category:** Coding Questions\
**Created:** [November 26, 2025, 7:06am UTC](https://discourse.processing.org/t/processing-exception/47566 "2025-11-26T07:06:42Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Frank](https://avatars.discourse-cdn.com/v4/letter/f/3d9bf3/32.png) [@Frank](https://discourse.processing.org/u/Frank)\
**Post date:** [November 26, 2025, 7:06am UTC](https://discourse.processing.org/t/processing-exception/47566/1 "2025-11-26T07:06:42Z")

</div>

Hello. I want to start an external program in Processing and Processing should detect whether this program has also been started. How can I realize this?  
I’m not familiar with these exceptions.  
Thanks…Frank

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**Author:** ![glv](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/glv/32/18785_2.png) [@glv](https://discourse.processing.org/u/glv)\
**Post date:** [November 26, 2025, 3:09pm UTC](https://discourse.processing.org/t/processing-exception/47566/2 "2025-11-26T15:09:54Z")

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Hello @Frank,

Welcome to the forum.

Processing provides a simple launch utility:

_[launch() / Reference / Processing.org](https://processing.org/reference/launch_.html)_

Example:  
`launch("notepad.exe"); // Works on Windows 10`

This is what `launch()` is doing “under the hood”:

_[processing4/core/src/processing/core/PApplet.java at main · processing/processing4 · GitHub](https://github.com/processing/processing4/blob/main/core/src/processing/core/PApplet.java#L3092)_

`launch()` is using the Java Runtime exec() method.

Since Processing runs on Java, you can also use standard Java libraries. If you prefer more control, look into `ProcessBuilder` and integrate it directly into your sketch.

Minimal example that works in static mode on W10:

```auto
try 
  {
  Process p = new ProcessBuilder("notepad.exe").start(); // Windows 
  println(p.isAlive());
  } 
catch (Exception e) 
  {
  }

```

Have fun!

`:)`

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<div class="post-metadata">

**Author:** ![Frank](https://avatars.discourse-cdn.com/v4/letter/f/3d9bf3/32.png) [@Frank](https://discourse.processing.org/u/Frank)\
**Post date:** [November 26, 2025, 11:26pm UTC](https://discourse.processing.org/t/processing-exception/47566/3 "2025-11-26T23:26:29Z")

</div>

Thank you very much. I’ll try it out tomorrow morning

Frank

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<div class="post-metadata">

**Author:** ![Frank](https://avatars.discourse-cdn.com/v4/letter/f/3d9bf3/32.png) [@Frank](https://discourse.processing.org/u/Frank)\
**Post date:** [December 4, 2025, 3:44am UTC](https://discourse.processing.org/t/processing-exception/47566/4 "2025-12-04T03:44:32Z")

</div>

Thank you, it works

Frank