virtualx-engine-docs/_sources/classes/class_thread.rst.txt
2024-10-23 09:41:33 -07:00

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.. DO NOT EDIT THIS FILE!!!
.. Generated automatically from Godot engine sources.
.. Generator: https://github.com/godotengine/godot/tree/3.6/doc/tools/make_rst.py.
.. XML source: https://github.com/godotengine/godot/tree/3.6/doc/classes/Thread.xml.
.. _class_Thread:
Thread
======
**Inherits:** :ref:`Reference<class_Reference>` **<** :ref:`Object<class_Object>`
A unit of execution in a process.
.. rst-class:: classref-introduction-group
Description
-----------
A unit of execution in a process. Can run methods on :ref:`Object<class_Object>`\ s simultaneously. The use of synchronization via :ref:`Mutex<class_Mutex>` or :ref:`Semaphore<class_Semaphore>` is advised if working with shared objects.
\ **Note:** Breakpoints won't break on code if it's running in a thread. This is a current limitation of the GDScript debugger.
\ **Warning:**\
To guarantee that the operating system is able to perform proper cleanup (no crashes, no deadlocks), these conditions must be met by the time a **Thread**'s reference count reaches zero and therefore it is destroyed:
- It must not have any :ref:`Mutex<class_Mutex>` objects locked.
- It must not be waiting on any :ref:`Semaphore<class_Semaphore>` objects.
- :ref:`wait_to_finish<class_Thread_method_wait_to_finish>` should have been called on it.
.. rst-class:: classref-introduction-group
Tutorials
---------
- :doc:`Using multiple threads <../tutorials/performance/threads/using_multiple_threads>`
- :doc:`Thread-safe APIs <../tutorials/performance/threads/thread_safe_apis>`
- `3D Voxel Demo <https://godotengine.org/asset-library/asset/676>`__
.. rst-class:: classref-reftable-group
Methods
-------
.. table::
:widths: auto
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`String<class_String>` | :ref:`get_id<class_Thread_method_get_id>` **(** **)** |const| |
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`bool<class_bool>` | :ref:`is_active<class_Thread_method_is_active>` **(** **)** |const| |
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`bool<class_bool>` | :ref:`is_alive<class_Thread_method_is_alive>` **(** **)** |const| |
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Error<enum_@GlobalScope_Error>` | :ref:`start<class_Thread_method_start>` **(** :ref:`Object<class_Object>` instance, :ref:`String<class_String>` method, :ref:`Variant<class_Variant>` userdata=null, :ref:`Priority<enum_Thread_Priority>` priority=1 **)** |
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Variant<class_Variant>` | :ref:`wait_to_finish<class_Thread_method_wait_to_finish>` **(** **)** |
+---------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
.. rst-class:: classref-section-separator
----
.. rst-class:: classref-descriptions-group
Enumerations
------------
.. _enum_Thread_Priority:
.. rst-class:: classref-enumeration
enum **Priority**:
.. _class_Thread_constant_PRIORITY_LOW:
.. rst-class:: classref-enumeration-constant
:ref:`Priority<enum_Thread_Priority>` **PRIORITY_LOW** = ``0``
A thread running with lower priority than normally.
.. _class_Thread_constant_PRIORITY_NORMAL:
.. rst-class:: classref-enumeration-constant
:ref:`Priority<enum_Thread_Priority>` **PRIORITY_NORMAL** = ``1``
A thread with a standard priority.
.. _class_Thread_constant_PRIORITY_HIGH:
.. rst-class:: classref-enumeration-constant
:ref:`Priority<enum_Thread_Priority>` **PRIORITY_HIGH** = ``2``
A thread running with higher priority than normally.
.. rst-class:: classref-section-separator
----
.. rst-class:: classref-descriptions-group
Method Descriptions
-------------------
.. _class_Thread_method_get_id:
.. rst-class:: classref-method
:ref:`String<class_String>` **get_id** **(** **)** |const|
Returns the current **Thread**'s ID, uniquely identifying it among all threads. If the **Thread** is not running this returns an empty string.
.. rst-class:: classref-item-separator
----
.. _class_Thread_method_is_active:
.. rst-class:: classref-method
:ref:`bool<class_bool>` **is_active** **(** **)** |const|
Returns ``true`` if this **Thread** has been started. Once started, this will return ``true`` until it is joined using :ref:`wait_to_finish<class_Thread_method_wait_to_finish>`. For checking if a **Thread** is still executing its task, use :ref:`is_alive<class_Thread_method_is_alive>`.
.. rst-class:: classref-item-separator
----
.. _class_Thread_method_is_alive:
.. rst-class:: classref-method
:ref:`bool<class_bool>` **is_alive** **(** **)** |const|
Returns ``true`` if this **Thread** is currently running. This is useful for determining if :ref:`wait_to_finish<class_Thread_method_wait_to_finish>` can be called without blocking the calling thread.
To check if a **Thread** is joinable, use :ref:`is_active<class_Thread_method_is_active>`.
.. rst-class:: classref-item-separator
----
.. _class_Thread_method_start:
.. rst-class:: classref-method
:ref:`Error<enum_@GlobalScope_Error>` **start** **(** :ref:`Object<class_Object>` instance, :ref:`String<class_String>` method, :ref:`Variant<class_Variant>` userdata=null, :ref:`Priority<enum_Thread_Priority>` priority=1 **)**
Starts a new **Thread** that runs ``method`` on object ``instance`` with ``userdata`` passed as an argument. Even if no userdata is passed, ``method`` must accept one argument and it will be null. The ``priority`` of the **Thread** can be changed by passing a value from the :ref:`Priority<enum_Thread_Priority>` enum.
Returns :ref:`@GlobalScope.OK<class_@GlobalScope_constant_OK>` on success, or :ref:`@GlobalScope.ERR_CANT_CREATE<class_@GlobalScope_constant_ERR_CANT_CREATE>` on failure.
.. rst-class:: classref-item-separator
----
.. _class_Thread_method_wait_to_finish:
.. rst-class:: classref-method
:ref:`Variant<class_Variant>` **wait_to_finish** **(** **)**
Joins the **Thread** and waits for it to finish. Returns the output of the method passed to :ref:`start<class_Thread_method_start>`.
Should either be used when you want to retrieve the value returned from the method called by the **Thread** or before freeing the instance that contains the **Thread**.
To determine if this can be called without blocking the calling thread, check if :ref:`is_alive<class_Thread_method_is_alive>` is ``false``.
\ **Note:** After the **Thread** finishes joining it will be disposed. If you want to use it again you will have to create a new instance of it.
.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`
.. |static| replace:: :abbr:`static (This method doesn't need an instance to be called, so it can be called directly using the class name.)`