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/*
     File: Reachability.h
 Abstract: Basic demonstration of how to use the SystemConfiguration Reachablity APIs.
  Version: 3.5
 
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 Neither the name, trademarks, service marks or logos of Apple Inc. may
 be used to endorse or promote products derived from the Apple Software
 without specific prior written permission from Apple.  Except as
 expressly stated in this notice, no other rights or licenses, express or
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 works in which the Apple Software may be incorporated.
 
 The Apple Software is provided by Apple on an "AS IS" basis.  APPLE
 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION
 THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS
 FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND
 OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.
 
 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL
 OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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 */

#import <Foundation/Foundation.h>
#import <SystemConfiguration/SystemConfiguration.h>
#import <netinet/in.h>


typedef enum : NSInteger {
	NotReachable = 0,
	ReachableViaWiFi,
	ReachableViaWWAN
} NetworkStatus;


extern NSString *kReachabilityChangedNotification;


@interface Reachability : NSObject

/*!
 * Use to check the reachability of a given host name.
 */
+ (instancetype)reachabilityWithHostName:(NSString *)hostName;

/*!
 * Use to check the reachability of a given IP address.
 */
+ (instancetype)reachabilityWithAddress:(const struct sockaddr_in *)hostAddress;

/*!
 * Checks whether the default route is available. Should be used by applications that do not connect to a particular host.
 */
+ (instancetype)reachabilityForInternetConnection;

/*!
 * Checks whether a local WiFi connection is available.
 */
+ (instancetype)reachabilityForLocalWiFi;

/*!
 * Start listening for reachability notifications on the current run loop.
 */
- (BOOL)startNotifier;
- (void)stopNotifier;

- (NetworkStatus)currentReachabilityStatus;

/*!
 * WWAN may be available, but not active until a connection has been established. WiFi may require a connection for VPN on Demand.
 */
- (BOOL)connectionRequired;

@end