Detect If Your Application Is Running In The Debugger

gistfile1.c

static bool debuggerRunning(void) {
  int                 junk;
  int                 mib[4];
  struct kinfo_proc   info;
  size_t              size;
 
  info.kp_proc.p_flag = 0;
 
  mib[0] = CTL_KERN;
  mib[1] = KERN_PROC;
  mib[2] = KERN_PROC_PID;
  mib[3] = getpid();
 
  size = sizeof(info);
  junk = sysctl(mib, sizeof(mib) / sizeof(*mib), &info, &size, NULL, 0);
  assert(junk == 0);
 
  // If P_TRACED flag set, debugger running
  return ( (info.kp_proc.p_flag & P_TRACED) != 0 );
}

gistfile2.m

// @see http://iosdevelopertips.com/debugging/detect-if-your-application-is-running-in-the-debugger.html
if (debuggerRunning())
  NSLog(@"Debugger running");
else
  NSLog(@"Debugger not running");