> For the complete documentation index, see [llms.txt](https://doc.sysdevmobile.com/kalipso5/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.sysdevmobile.com/kalipso5/developing/form/actions/actions-description/group-code-flow/critical-section-leave.md).

# Critical Section Leave

A critical section is a part of your application that you don’t want to be executed simultaneously by other threads. When you call “Critical Section Enter” action the call only returns if there is no other Thread inside the same critical section. After the call returns, no other thread can enter the same critical section until a call to “Critical Section Leave” action is made by the current thread.

This action defines the end of a critical section, and it means other threads can now enter the same critical section.

Action available for the following operating systems:

![](/files/-MAlQBZuuTnc6hyzKSVQ)

### Parameters

* **Critical Section Id** *\<numeric> -* Defines the handler for critical section. There are 10 pre-defined handlers for critical sections.

{% hint style="info" %}
This action must be used in conjuction to [Critical Section Enter](/kalipso5/developing/form/actions/actions-description/group-code-flow/critical-section-enter.md) action.
{% endhint %}

{% hint style="info" %}
You should call this action in the same **event** or **action set** that called Critical Section Enter.
{% endhint %}