title: Undefined symbols for architecture i386: "_SCNetworkReachabilitySetCallback"
body: <p>I use xcode4, on a openglES project
  i have added code for in-app purchase from the tutorial:
  <a href="http://www.raywenderlich.com/2797/introduction-to-in-app-purchases" rel="nofollow noreferrer">http://www.raywenderlich.com/2797/introduction-to-in-app-purchases</a></p>
  
  <p>i have added SystemConfiguration.framework but this errors occurs:</p>
  
  <pre><code>Ld /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator/blatest.app/blatest normal i386
      cd /Users/Eros/Desktop/blatestDB
      setenv MACOSX_DEPLOYMENT_TARGET 10.6
      setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
      /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk -L/Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator -F/Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator -F/Users/Eros/Desktop/blatestDB -filelist /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Intermediates/blatest.build/Debug-iphonesimulator/SLQTSOR.build/Objects-normal/i386/blatest.LinkFileList -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -framework Foundation -framework UIKit -framework OpenGLES -framework QuartzCore -framework AVFoundation -framework AudioToolbox -framework CoreAudio -framework CoreGraphics -framework OpenAL -lz -framework MediaPlayer -framework AVFoundation -framework GameKit -framework StoreKit -o /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator/blatest.app/blatest
  
  Undefined symbols for architecture i386:
    "_SCNetworkReachabilitySetCallback", referenced from:
        -[Reachability startNotifier] in Reachability.o
    "_SCNetworkReachabilityScheduleWithRunLoop", referenced from:
        -[Reachability startNotifier] in Reachability.o
    "_SCNetworkReachabilityUnscheduleFromRunLoop", referenced from:
        -[Reachability stopNotifier] in Reachability.o
    "_SCNetworkReachabilityGetFlags", referenced from:
        -[Reachability currentReachabilityStatus] in Reachability.o
        -[Reachability connectionRequired] in Reachability.o
    "_SCNetworkReachabilityCreateWithName", referenced from:
        +[Reachability reachabilityWithHostName:] in Reachability.o
    "_SCNetworkReachabilityCreateWithAddress", referenced from:
        +[Reachability reachabilityWithAddress:] in Reachability.o
  ld: symbol(s) not found for architecture i386
  collect2: ld returned 1 exit status
  </code></pre>
  
  <p>if i delete framework reference the error is the same. 
  adding again nothing happens...
  in -Xlinker 2 -framework Foundation -framework UIKit [...] should i see "-framework SystemConfiguration" right?
  why is not there?
  do anyone has ideas?</p>
  
  <p>pulling up the framework from the project->build phases->link binary with library making it the first framework i have this erros:</p>
  
  <pre><code>Ld /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator/blatest.app/blatest normal i386
      cd /Users/Eros/Desktop/blatestDB
      setenv MACOSX_DEPLOYMENT_TARGET 10.6
      setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
      /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk -L/Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator -F/Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator -F/Users/Eros/Desktop/blatestDB -filelist /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Intermediates/blatest.build/Debug-iphonesimulator/SLQTSOR.build/Objects-normal/i386/blatest.LinkFileList -mmacosx-version-min=10.6 -Xlinker -objc_abi_version -Xlinker 2 -framework SystemConfiguration -framework Foundation -framework UIKit -framework OpenGLES -framework QuartzCore -framework AVFoundation -framework AudioToolbox -framework CoreAudio -framework CoreGraphics -framework OpenAL -lz -framework MediaPlayer -framework AVFoundation -framework GameKit -framework StoreKit -o /Users/Eros/Library/Developer/Xcode/DerivedData/blatest-acmdklrqungznggpjewgxuxqsvwo/Build/Products/Debug-iphonesimulator/blatest.app/blatest
  
  ld: warning: ignoring file /Users/Eros/Desktop/blatestDB/SystemConfiguration.framework/SystemConfiguration, missing required architecture i386 in file
  Undefined symbols for architecture i386:
    "_SCNetworkReachabilitySetCallback", referenced from:
        -[Reachability startNotifier] in Reachability.o
    "_SCNetworkReachabilityScheduleWithRunLoop", referenced from:
        -[Reachability startNotifier] in Reachability.o
    "_SCNetworkReachabilityUnscheduleFromRunLoop", referenced from:
        -[Reachability stopNotifier] in Reachability.o
    "_SCNetworkReachabilityGetFlags", referenced from:
        -[Reachability currentReachabilityStatus] in Reachability.o
        -[Reachability connectionRequired] in Reachability.o
    "_SCNetworkReachabilityCreateWithName", referenced from:
        +[Reachability reachabilityWithHostName:] in Reachability.o
    "_SCNetworkReachabilityCreateWithAddress", referenced from:
        +[Reachability reachabilityWithAddress:] in Reachability.o
  ld: symbol(s) not found for architecture i386
  collect2: ld returned 1 exit status
  </code></pre>
  
  <p>SystemConfiguration is there, the error still there...
  what can it be?
  thanks</p>