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# CMIOExtensionClient

An object that represents a client of the extension.

```
class CMIOExtensionClient
```

## Topics

### Identifying a Client

[`var clientID: UUID`](/documentation/CoreMediaIO/CMIOExtensionClient/clientID)

A unique client identifier.

[`var pid: pid_t`](/documentation/CoreMediaIO/CMIOExtensionClient/pid)

The process identifier of the client.

### Instance Properties

[`var signingID: String?`](/documentation/CoreMediaIO/CMIOExtensionClient/signingID)

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`Equatable`](/documentation/Swift/Equatable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CVarArg`](/documentation/Swift/CVarArg)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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