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  "title" : "CFStream Error Domain Constants (CFHost)"
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# CFStream Error Domain Constants (CFHost)

Defines constants for values returned in the domain field of the `CFStreamError` structure.

## Discussion

These constants indicate how the error code in the `error` field in the [`CFStreamError`](/documentation/CoreFoundation/CFStreamError) structure should be interpreted.

## Topics

### Constants

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainNetDB>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainNetServices>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainMach>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainFTP>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainHTTP>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainSystemConfiguration>

  <doc://com.apple.documentation/documentation/CFNetwork/kCFStreamErrorDomainWinSock>

[`let kCFStreamErrorDomainSOCKS: Int32`](/documentation/CoreFoundation/kCFStreamErrorDomainSOCKS)

The error code is a SOCKS proxy error.

[`let kCFStreamErrorDomainSSL: Int32`](/documentation/CoreFoundation/kCFStreamErrorDomainSSL)

The error code is an SSL error code as defined in `Security/SecureTransport.h`.


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