dlopen在应用程序终止后返回NULL

我正在使用 dlsym 要加载私有API(iOS 9.3要求):

handle = dlopen(CORETELPATH, RTLD_LAZY);
_CTServerConnectionCreate = dlsym(handle, "_CTServerConnectionCreate");

当我关闭应用程序(在多任务模式下从底部滑动)并重新启动应用程序时,它会在第二行崩溃。

这个 handle 等于 NULL 我没有成功加载两次库。

我试图用 dlerror() ,但它也会返回 无效的 .

有人知道这个问题吗?如何解决?

编辑: 这是完整的代码;使用 if (handle != NULL) 应用程序不会崩溃,但私有框架也不会加载

#define CORETELPATH "/System/Library/PrivateFrameworks/CoreTelephony.framework/CoreTelephony"

handle = dlopen(CORETELPATH, RTLD_LAZY);
            NSLog(@"DL Error : %s", dlerror());
            if (handle != NULL) {
                _CTServerConnectionCreate = dlsym(handle, "_CTServerConnectionCreate");
                CTResultConnection = _CTServerConnectionCreate(NULL, simMonitorCallback, NULL);
                _CTServerConnectionAddToRunLoop = dlsym(handle, "_CTServerConnectionAddToRunLoop");
                _CTServerConnectionAddToRunLoop(CTResultConnection, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
                _CTServerConnectionRegisterForNotification = dlsym(handle, "_CTServerConnectionRegisterForNotification");
                _CTServerConnectionUnregisterForNotification = dlsym(handle, "_CTServerConnectionUnregisterForNotification");
                _CTServerConnectionRegisterForNotification(CTResultConnection, kCTSIMSupportSIMStatusChangeNotification);
                _CTServerConnectionGetSIMStatus = dlsym(handle, "_CTServerConnectionGetSIMStatus");
                _CTServerConnectionCopyMobileEquipmentInfo = dlsym(handle, "_CTServerConnectionCopyMobileEquipmentInfo");
            }