# MemClear(void*, long)

> Clears a block of memory, setting all bytes to zero.

## Definition

* **Type:** Method
* **Namespace:** [Unity.Collections.LowLevel.Unsafe](/engine/6000.0/script-reference/unity/collections/lowlevel/unsafe.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
public static void MemClear(void* destination, long size)
```

### Parameters

**** (\[void\*]\(https\://learn.microsoft.com/dotnet/api/system.void)): A pointer to the start of the memory block you want to clear. Ensure this pointer is valid and that the memory region is correctly allocated.**** (\[long]\(https\://learn.microsoft.com/dotnet/api/system.int64)): The number of bytes to clear in the memory block. Ensure this size does not exceed the allocated memory to avoid data corruption.

### Remarks

The `MemClear` method sets all bytes in a specified memory block to zero. This is useful for initializing memory without any residual data that might cause unexpected behavior. Use this method to ensure memory safety when reusing or reallocating memory blocks.

This method provides a fast and efficient way to clear data, which is important in scenarios where performance and reliability are paramount. It is often used when you need to reset arrays or buffers before further processing.

```csharp
using UnityEngine;
using Unity.Collections.LowLevel.Unsafe;

public class MemClearExample : MonoBehaviour
{
    void Start()
    {
        int bufferSize = 10;

        // Allocate a buffer using stackalloc
        unsafe
        {
            byte* buffer = stackalloc byte[bufferSize];

            // Initialize the buffer with some data
            for (int i = 0; i < bufferSize; i++)
            {
                buffer[i] = (byte)(i + 1);
            }

            // Output the buffer contents before clearing
            Debug.Log("Buffer contents before MemClear:");
            for (int i = 0; i < bufferSize; i++)
            {
                Debug.Log(buffer[i]);
            }

            // Clear the buffer using MemClear
            UnsafeUtility.MemClear(buffer, bufferSize);

            // Output the buffer contents after clearing
            Debug.Log("Buffer contents after MemClear:");
            for (int i = 0; i < bufferSize; i++)
            {
                Debug.Log(buffer[i]);  // Expected output: 0 for each element
            }
        }
    }
}
```

Additional Resources: [UnsafeUtility.MemSet](/engine/6000.0/script-reference/unity/collections/lowlevel/unsafe/unsafeutility/memset.md).