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# asif(url:blockCount:blockSize:)

Returns an Apple sparse image format (ASIF) configuration for standalone or base images.

```
static func asif(url: URL, blockCount: Int, blockSize: DiskImage.BlockSize) -> Self
```

## Parameters

`url`

The <doc://com.apple.documentation/documentation/Foundation/URL> for the disk image file.

`blockCount`

Size of the disk image in blocks.

`blockSize`

The [`DiskImage.BlockSize`](/documentation/DiskImageKit/DiskImage/BlockSize-swift.enum) to use.

## Return Value

An [`ASIFCreationConfiguration`](/documentation/DiskImageKit/ASIFCreationConfiguration) instance for standalone use.

## Discussion

Use this initializer when creating a standalone image, or a base image for a stack, using [`init(creating:)`](/documentation/DiskImageKit/DiskImage/init(creating:)).
To create a cache or overlay layer for a stacked disk image, use [`asifLayer(url:type:)`](/documentation/DiskImageKit/DiskImage/CreationConfiguration/asifLayer(url:type:)) instead.

The following example demonstrates how to create a ASIF disk image:

```
_ = try DiskImage(creating: .asif(url: imageURL, blockCount: blockCount, blockSize: .bytes512))
```

---

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