# interlocked\_compare\_exchange

### Function

> interlocked\_compare\_exchange

### Syntax

> interlocked\_compare\_exchange( \*Variable, Expression, Expression );

### Parameters

**\[\*Variable (Destination)]**

A reference to a variable (most of the time a global variable) that is compared with the value of **Comperand**.

**\[Expression (ExChange)]**

Specifies the output value pointed to by **Destination** if the input value pointed to by **Destination** equals the value of **Comperand**.

**\[Expression (Comperand)]**

Specifies the value that is compared with the input value pointed to by **Destination**.

### Description

Performs an atomic operation that compares the input value pointed to by **Destination** with the value of **Comperand**. If **Comperand** is equal to **Destination**, then **Destination** is set to equal **Exchange**. Otherwise, **Destination** is unchanged.

### Return value

The function returns the original value of **\*Destination**.

### Examples

None

### Remarks

None

### Related

[interlocked\_exchange\_add](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_exchange_add)

[interlocked\_increment](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_increment)

[interlocked\_exchange](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_exchange)

[interlocked\_decrement](https://docs.hyperdbg.org/commands/scripting-language/functions/interlocked/interlocked_decrement)