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# CMSDecoderCreate(_:)

Creates a CMSDecoder reference.

```
func CMSDecoderCreate(_ cmsDecoderOut: UnsafeMutablePointer<CMSDecoder?>) -> OSStatus
```

## Parameters

`cmsDecoderOut`

On return, points to a CMSDecoder reference. You must use the `CFRelease` function to free this reference when you are finished using it.

## Return Value

A result code. See [Security Framework Result Codes](/documentation/Security/security-framework-result-codes).

## Discussion

This is the first function in a sequence of decoder functions that you call to get information from a CMS message. The other functions in the sequence require you to pass in the CMSDecoder reference returned by this function. The next function in the sequence is `CMSDecoderUpdateMessage`.

## See Also

[`CMSDecoderUpdateMessage(_:_:_:)`](/documentation/Security/CMSDecoderUpdateMessage(_:_:_:))

Feeds raw bytes of the message to be decoded into the decoder.


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