title: understand iOS crash log
body: <p>Could someone please help me understand this crash report. I can't make head or tail of it.</p>
  
  <pre><code>Exception Type:  EXC_CRASH (SIGABRT)
  Exception Codes: 0x0000000000000000, 0x0000000000000000
  Triggered by Thread:  8
  
  Last Exception Backtrace:
  0   CoreFoundation                  0x2ec73fce __exceptionPreprocess + 126
  1   libobjc.A.dylib                 0x3983dcca objc_exception_throw + 34
  2   CoreFoundation                  0x2ec73ea8 +[NSException raise:format:arguments:] + 96
  3   Foundation                      0x2f620d56 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 86
  4   UIKit                           0x314bce9a -[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] + 166
  5   UIKit                           0x314cdaf4 -[UIKeyboardImpl prepareForSelectionChange] + 88
  6   UIKit                           0x314afe10 -[UIFieldEditor setAttributedText:andSetCaretSelectionAfterText:] + 52
  7   UIKit                           0x314cd77a -[UIFieldEditor setText:andSetCaretSelectionAfterText:] + 130
  8   UIKit                           0x314cd508 -[UITextField setText:] + 220
  9   UIKit                           0x316852c8 -[UISearchBar setText:] + 40
  10  Farm Hand                       0x0009b906 0x7000 + 608518
  11  Foundation                      0x2f65ca5a __NSThread__main__ + 1058
  12  libsystem_pthread.dylib         0x39e69914 _pthread_body + 136
  13  libsystem_pthread.dylib         0x39e69886 _pthread_start + 98
  14  libsystem_pthread.dylib         0x39e67aa0 thread_start + 4
  
  
  Thread 0:
  0   libsystem_kernel.dylib          0x39deda58 mach_msg_trap + 20
  1   libsystem_kernel.dylib          0x39ded854 mach_msg + 44
  2   CoreFoundation                  0x2ec3e896 __CFRunLoopServiceMachPort + 150
  3   CoreFoundation                  0x2ec3d002 __CFRunLoopRun + 850
  4   CoreFoundation                  0x2eba7f0a CFRunLoopRunSpecific + 518
  5   CoreFoundation                  0x2eba7cee CFRunLoopRunInMode + 102
  6   GraphicsServices                0x33acd65e GSEventRunModal + 134
  7   UIKit                           0x314f3168 UIApplicationMain + 1132
  8   Farm Hand                       0x0009de44 0x7000 + 618052
  9   libdyld.dylib                   0x39d4aab4 start + 0
  
  Thread 1:
  0   libsystem_kernel.dylib          0x39ded808 kevent64 + 24
  1   libdispatch.dylib               0x39d2f078 _dispatch_mgr_invoke + 228
  2   libdispatch.dylib               0x39d2edfe _dispatch_mgr_thread$VARIANT$mp + 34
  
  Thread 2:
  0   libsystem_kernel.dylib          0x39deda58 mach_msg_trap + 20
  1   libsystem_kernel.dylib          0x39ded854 mach_msg + 44
  2   CoreFoundation                  0x2ec3e896 __CFRunLoopServiceMachPort + 150
  3   CoreFoundation                  0x2ec3cfbc __CFRunLoopRun + 780
  4   CoreFoundation                  0x2eba7f0a CFRunLoopRunSpecific + 518
  5   CoreFoundation                  0x2ebeb9fe CFRunLoopRun + 94
  6   CoreMotion                      0x2f2653a8 ___lldb_unnamed_function1423$$CoreMotion + 724
  7   libsystem_pthread.dylib         0x39e69916 _pthread_body + 138
  8   libsystem_pthread.dylib         0x39e69886 _pthread_start + 98
  9   libsystem_pthread.dylib         0x39e67aa0 thread_start + 4
  
  Thread 3 name:  com.apple.CFSocket.private
  Thread 3:
  0   libsystem_kernel.dylib          0x39e00434 __select + 20
  1   CoreFoundation                  0x2ec42758 __CFSocketManager + 480
  2   libsystem_pthread.dylib         0x39e69916 _pthread_body + 138
  3   libsystem_pthread.dylib         0x39e69886 _pthread_start + 98
  4   libsystem_pthread.dylib         0x39e67aa0 thread_start + 4
  
  Thread 4:
  0   libsystem_kernel.dylib          0x39df11a8 kevent + 24
  1   ExternalAccessory               0x2f58567a -[EAInputStream _readInputFromAccThread] + 382
  2   Foundation                      0x2f65ca5a __NSThread__main__ + 1058
  3   libsystem_pthread.dylib         0x39e69916 _pthread_body + 138
  4   libsystem_pthread.dylib         0x39e69886 _pthread_start + 98
  5   libsystem_pthread.dylib         0x39e67aa0 thread_start + 4
  
  Thread 5:
  0   libsystem_kernel.dylib          0x39e00c70 __workq_kernreturn + 8
  1   libsystem_pthread.dylib         0x39e67bda _pthread_wqthread + 306
  2   libsystem_pthread.dylib         0x39e67a94 start_wqthread + 4
  
  Thread 6:
  0   libsystem_kernel.dylib          0x39e00c70 __workq_kernreturn + 8
  1   libsystem_pthread.dylib         0x39e67bda _pthread_wqthread + 306
  2   libsystem_pthread.dylib         0x39e67a94 start_wqthread + 4
  
  Thread 7:
  0   libsystem_kernel.dylib          0x39e00c70 __workq_kernreturn + 8
  1   libsystem_pthread.dylib         0x39e67bda _pthread_wqthread + 306
  2   libsystem_pthread.dylib         0x39e67a94 start_wqthread + 4
  
  Thread 8 Crashed:
  0   libsystem_kernel.dylib          0x39e001f0 __pthread_kill + 8
  1   libsystem_pthread.dylib         0x39e6a792 pthread_kill + 54
  2   libsystem_c.dylib               0x39db0fd8 abort + 72
  3   libc++abi.dylib                 0x390dfcd2 abort_message + 70
  4   libc++abi.dylib                 0x390f86e0 default_terminate_handler() + 248
  5   libobjc.A.dylib                 0x3983df62 _objc_terminate() + 190
  6   libc++abi.dylib                 0x390f61c4 std::__terminate(void (*)()) + 76
  7   libc++abi.dylib                 0x390f5a18 __cxa_throw + 112
  8   libobjc.A.dylib                 0x3983dd9e objc_exception_throw + 246
  9   CoreFoundation                  0x2ec73ea8 +[NSException raise:format:arguments:] + 96
  10  Foundation                      0x2f620d56 -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 86
  11  UIKit                           0x314bce9a -[UIKeyboardTaskQueue waitUntilAllTasksAreFinished] + 166
  12  UIKit                           0x314cdaf4 -[UIKeyboardImpl prepareForSelectionChange] + 88
  13  UIKit                           0x314afe10 -[UIFieldEditor setAttributedText:andSetCaretSelectionAfterText:] + 52
  14  UIKit                           0x314cd77a -[UIFieldEditor setText:andSetCaretSelectionAfterText:] + 130
  15  UIKit                           0x314cd508 -[UITextField setText:] + 220
  16  UIKit                           0x316852c8 -[UISearchBar setText:] + 40
  17  Farm Hand                       0x0009b908 0x7000 + 608520
  18  Foundation                      0x2f65ca5a __NSThread__main__ + 1058
  19  libsystem_pthread.dylib         0x39e69916 _pthread_body + 138
  20  libsystem_pthread.dylib         0x39e69886 _pthread_start + 98
  21  libsystem_pthread.dylib         0x39e67aa0 thread_start + 4
  
  Thread 8 crashed with ARM Thread State (32-bit):
      r0: 0x00000000    r1: 0x00000000      r2: 0x00000000      r3: 0x00002060
      r4: 0x00000006    r5: 0x04d2f000      r6: 0x00000000      r7: 0x04d2dd14
      r8: 0x1804a3c0    r9: 0x00000001     r10: 0x31ae10c8     r11: 0x00000000
      ip: 0x00000148    sp: 0x04d2dd08      lr: 0x39e6a797      pc: 0x39e001f0
    cpsr: 0x00000010
  </code></pre>
  
  <p>I'm using the ExternalAccessory framework which I've had problems with in the past and the App crashed whilst receiving data from a bluetooth connected external device. However, I can't tell if that was what caused the crash.</p>
  
  <p>Thanks in advance.</p>