---
name: "SDL_CompareAndSwapAtomicU32"
section: "3"
platform: "linux"
package: "libsdl3-doc"
version: "3.2.10+ds-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/SDL_CompareAndSwapAtomicU32"
---

# SDL\_CompareAndSwapAtomicU32(3)

Set an atomic variable to a new value if it is currently an old value.

## NAME

SDL\_CompareAndSwapAtomicU32 - Set an atomic variable to a new value if it is currently an old value.

## HEADER FILE

Defined in SDL3/SDL\_atomic.h

## SYNOPSIS

```
#include "SDL3/SDL.h"
```

**bool SDL\_CompareAndSwapAtomicU32(SDL\_AtomicU32 \*a, Uint32 oldval, Uint32 newval);**

## DESCRIPTION

**Note: If you don't know what this function is for, you shouldn't use** it!

## FUNCTION PARAMETERS

- *a*

  a pointer to an  **SDL\_AtomicU32**\
    variable to be modified.

- *oldval*

  the old value.

- *newval*

  the new value.

## RETURN VALUE

Returns true if the atomic variable was set, false otherwise.

## THREAD SAFETY

It is safe to call this function from any thread.

## AVAILABILITY

This function is available since SDL 3.2.0.

## SEE ALSO

**•**(3), [**SDL\_GetAtomicU32**(3)](/SDL_GetAtomicU32/3.md), **•**(3), [**SDL\_SetAtomicU32**(3)](/SDL_SetAtomicU32/3.md)