<!--
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  "framework" : "CoreTelephony",
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  "title" : "Error Domains"
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# Error Domains

Error domains used by Core Telephony errors.

## Topics

### Error Domains

[`var kCTErrorDomainMach: Int`](/documentation/CoreTelephony/kCTErrorDomainMach)

The domain value for errors reported by Mach.

[`var kCTErrorDomainNoError: Int`](/documentation/CoreTelephony/kCTErrorDomainNoError)

The domain value indicating there is no error.

[`var kCTErrorDomainPOSIX: Int`](/documentation/CoreTelephony/kCTErrorDomainPOSIX)

The domain value for errors from POSIX.


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