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  "title" : "Global Constants"
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# Global Constants

## Topics

### Constants

[`extern NSString * const CWBSSIDDidChangeNotification;`](/documentation/CoreWLAN/CWBSSIDDidChangeNotification)

[`extern NSString * const CWCountryCodeDidChangeNotification;`](/documentation/CoreWLAN/CWCountryCodeDidChangeNotification)

[`let CWErrorDomain: String`](/documentation/CoreWLAN/CWErrorDomain)

[`extern NSString * const CWLinkDidChangeNotification;`](/documentation/CoreWLAN/CWLinkDidChangeNotification)

[`extern NSString * const CWLinkQualityDidChangeNotification;`](/documentation/CoreWLAN/CWLinkQualityDidChangeNotification)

[`let CWLinkQualityNotificationRSSIKey: String`](/documentation/CoreWLAN/CWLinkQualityNotificationRSSIKey)

[`let CWLinkQualityNotificationTransmitRateKey: String`](/documentation/CoreWLAN/CWLinkQualityNotificationTransmitRateKey)

[`extern NSString * const CWModeDidChangeNotification;`](/documentation/CoreWLAN/CWModeDidChangeNotification)

[`extern NSString * const CWPowerDidChangeNotification;`](/documentation/CoreWLAN/CWPowerDidChangeNotification)

[`extern NSString * const CWScanCacheDidUpdateNotification;`](/documentation/CoreWLAN/CWScanCacheDidUpdateNotification)

[`extern NSString * const CWSSIDDidChangeNotification;`](/documentation/CoreWLAN/CWSSIDDidChangeNotification)


---

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