# memcpy

### Function

> memcpy

### Syntax

> memcpy( Destination, Source, Num );

### Parameters

**\[Destination]**

A [MASM-like expression](https://docs.hyperdbg.org/commands/scripting-language/assumptions-and-evaluations) to evaluate which is the address of the **destination** buffer.

**\[Source]**

A [MASM-like expression](https://docs.hyperdbg.org/commands/scripting-language/assumptions-and-evaluations) to evaluate which is the address of the **source** buffer.

**\[Num]**

A [MASM-like expression](https://docs.hyperdbg.org/commands/scripting-language/assumptions-and-evaluations) to evaluate which is the size (length) of the bytes to be copied.

### Description

Copies the contents of the source address to the destination buffer.

### Return value

None

### Examples

``memcpy(fffff806`6de00000 , @rax, 40);``

Copies **0x40** bytes from the buffer pointed by the **RAX** register to the buffer which its address is ``fffff806`6de00000``.

`memcpy($buffer, @rsp, 16);`

Copies **0x16** bytes from the stack to the buffer allocated by the event buffer.

### Remarks

Please note that the size argument is passed in the **HEX** format.

Make sure to acquire a spinlock if the destination buffer might be accessed by different cores simultaneously.

This function checks for the validity of both the source and the destination address before performing the copy. 

The support for this function is added from **v0.2**.

### Related

[memcpy\_pa](https://docs.hyperdbg.org/commands/scripting-language/functions/memory/memcpy_pa)


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