NSURLErrorUnknown = -1,

NSURLErrorCancelled = -999,

NSURLErrorBadURL = -1000,

NSURLErrorTimedOut = -1001,

NSURLErrorUnsupportedURL = -1002,

NSURLErrorCannotFindHost = -1003,

NSURLErrorCannotConnectToHost = -1004,

NSURLErrorNetworkConnectionLost = -1005,

NSURLErrorDNSLookupFailed = -1006,

NSURLErrorHTTPTooManyRedirects = -1007,

NSURLErrorResourceUnavailable = -1008,

NSURLErrorNotConnectedToInternet = -1009,

NSURLErrorRedirectToNonExistentLocation = -1010,

NSURLErrorBadServerResponse = -1011,

NSURLErrorUserCancelledAuthentication = -1012,

NSURLErrorUserAuthenticationRequired = -1013,

NSURLErrorZeroByteResource = -1014,

NSURLErrorCannotDecodeRawData =            -1015,

NSURLErrorCannotDecodeContentData =        -1016,

NSURLErrorCannotParseResponse =            -1017,

NSURLErrorAppTransportSecurityRequiresSecureConnection NS_ENUM_AVAILABLE(10_11, 9_0) = -1022,

NSURLErrorFileDoesNotExist = -1100,

NSURLErrorFileIsDirectory = -1101,

NSURLErrorNoPermissionsToReadFile = -1102,

NSURLErrorDataLengthExceedsMaximum NS_ENUM_AVAILABLE(10_5, 2_0) = -1103,

// SSL errors

NSURLErrorSecureConnectionFailed = -1200,

NSURLErrorServerCertificateHasBadDate = -1201,

NSURLErrorServerCertificateUntrusted = -1202,

NSURLErrorServerCertificateHasUnknownRoot = -1203,

NSURLErrorServerCertificateNotYetValid = -1204,

NSURLErrorClientCertificateRejected = -1205,

NSURLErrorClientCertificateRequired = -1206,

NSURLErrorCannotLoadFromNetwork = -2000,

// Download and file I/O errors

NSURLErrorCannotCreateFile = -3000,

NSURLErrorCannotOpenFile = -3001,

NSURLErrorCannotCloseFile = -3002,

NSURLErrorCannotWriteToFile = -3003,

NSURLErrorCannotRemoveFile = -3004,

NSURLErrorCannotMoveFile = -3005,

NSURLErrorDownloadDecodingFailedMidStream = -3006,

NSURLErrorDownloadDecodingFailedToComplete =-3007,

NSURLErrorInternationalRoamingOff NS_ENUM_AVAILABLE(10_7, 3_0) =        -1018,

NSURLErrorCallIsActive NS_ENUM_AVAILABLE(10_7, 3_0) =                    -1019,

NSURLErrorDataNotAllowed NS_ENUM_AVAILABLE(10_7, 3_0) =                  -1020,

NSURLErrorRequestBodyStreamExhausted NS_ENUM_AVAILABLE(10_7, 3_0) =      -1021,

NSURLErrorBackgroundSessionRequiresSharedContainer NS_ENUM_AVAILABLE(10_10, 8_0) = -995,

NSURLErrorBackgroundSessionInUseByAnotherProcess NS_ENUM_AVAILABLE(10_10, 8_0) = -996,

NSURLErrorBackgroundSessionWasDisconnected NS_ENUM_AVAILABLE(10_10, 8_0)= -997,

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