title: Linker command failed error when using Tonymillion Rechability class
body: <p>I am getting this linked error in tonymillion Reachability class. I am using this to get the internet connection in my ios app. Anyone tell me why is this error coming. </p>
  
  <pre><code>Ld /Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Products/Debug-iphoneos/ResQ-mobile.app/ResQ-mobile normal arm64
  
  cd /Users/Mathaly/Desktop/Gunjan/Business/LogicRoots/Game/Mathaly2/proj.ios_mac
  
  export IPHONEOS_DEPLOYMENT_TARGET=6.0
  
  export PATH="/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
  /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch arm64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.4.sdk -L/Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Products/Debug-iphoneos -F/Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Products/Debug-iphoneos -filelist /Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Intermediates/ResQ.build/Debug-iphoneos/ResQ.build/Objects-normal/arm64/ResQ-mobile.LinkFileList -dead_strip -stdlib=libc++ -fobjc-link-runtime -miphoneos-version-min=6.0 -liconv -framework Security /Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Products/Debug-iphoneos/libcocos2d\ iOS.a -framework CoreMotion -framework Foundation -framework UIKit -framework CoreGraphics -framework OpenGLES -lz -framework QuartzCore -framework OpenAL -framework AVFoundation -framework AudioToolbox -Xlinker -dependency_info -Xlinker /Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Intermediates/ResQ.build/Debug-iphoneos/ResQ.build/Objects-normal/arm64/ResQ-mobile_dependency_info.dat -o /Users/Mathaly/Library/Developer/Xcode/DerivedData/ResQ-bkakeqfqsmrivngctueeyzttnpno/Build/Products/Debug-iphoneos/ResQ-mobile.app/ResQ-mobile
  
  Undefined symbols for architecture arm64:
  
    "_SCNetworkReachabilityGetFlags", referenced from:
        -[Reachability isReachable] in Reachability.o
        -[Reachability isReachableViaWWAN] in Reachability.o
        -[Reachability isReachableViaWiFi] in Reachability.o
        -[Reachability connectionRequired] in Reachability.o
        -[Reachability isConnectionOnDemand] in Reachability.o
        -[Reachability isInterventionRequired] in Reachability.o
        -[Reachability reachabilityFlags] in Reachability.o
        ...
  
    "_SCNetworkReachabilitySetDispatchQueue", referenced from:
        -[Reachability startNotifier] in Reachability.o
        -[Reachability stopNotifier] in Reachability.o
  
    "_SCNetworkReachabilitySetCallback", referenced from:
        -[Reachability startNotifier] in Reachability.o
        -[Reachability stopNotifier] in Reachability.o
  
    "_SCNetworkReachabilityCreateWithAddress", referenced from:
        +[Reachability reachabilityWithAddress:] in Reachability.o
  
    "_SCNetworkReachabilityCreateWithName", referenced from:
        +[Reachability reachabilityWithHostname:] in Reachability.o
  
  ld: symbol(s) not found for architecture arm64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>