CoreOSLayer

Manage the virtual memory system, threads, the file system, the network, and interprocess communication with the frameworks in the Core OS layer. This layer encompasses the kernel environment, drivers, and basic interfaces of iOS. The drivers at this layer also provide the interface between the available hardware and the system frameworks that vend hardware features. Use the frameworks in this layer if those in the upper layers aren't sufficient for your needs.
使用CoreOSLayer下的frameworks可以用来管理虚拟内存系统,线程,文件系统,网络,以及进程间的通信. 这一层包含了内核环境,驱动,以及iOS的基本接口. 这一层的驱动也提供了可用硬件和系统框架间运用硬件特性的接口. 该层下的frameworks可以满足其他层次所无法满足的需求,也就是说这是最基础的层次了.

1Accelerate

Perform complex math or image calculations with the Accelerate framework.
Accelerate用于执行复杂的数学或图像计算
Tips: C框架 前缀AC 访问重力加速计API

2CoreBluetooth

Communicate with Bluetooth 4.0 low-energy devices using the Core Bluetooth framework.
CoreBluetooth用于与蓝牙4.0低能耗设备交流.
Tips: OC框架 前缀CB 访问低能耗蓝牙设备API

3ExternalAccessory

Communicate with accessories connected to an iOS-based device with the External Accessory framework. Use it to interact with accessories connected through the Apple Lightning (or 30-pin) connector or wirelessly via Bluetooth.
ExternalAccessory用于与连接到iOS设备上的配件进行交流.这些配件可以是通过雷电接口(或者30针接口)连接器或者无线蓝牙进行连接的设备.
Tips: OC框架 前缀EA 访问外围配件API

4LocalAuthentication

Request authentication from users through passphrases or biometrics with the Local Authentication framework.
LocalAuthentication用户请求用户通过密码或者生物识别技术授予的权限.
Tips: OC框架 前缀LA 通过用户指定的安全策略进行安全认证,比如指纹

5NetworkExtension

Configure and control Virtual Private Network (VPN) tunnels using the Network Extension framework.
NetworkExtension用于配置及管理虚拟私有网络通道.
Tips: OC框架 前缀NE,NW

6Security

Secure the data your app manages with the Security framework. This framework defines C interfaces for protecting information and controlling access to software.
Security用于保障你的应用管理的数据.这个框架定义了C接口保护信息和控制软件的访问。
Tips: C框架 前缀CF 管理证书,公钥,私钥和安全信任策略的API

7System

The System framework offers a number of BSD and POSIX functions, such as a subset of UNIX system calls and C library routines.
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Tips: 其他的一些系统相关的玩意