探究苹果技术原理和学习新技术(锲而舍之，朽木不折；锲而不舍，金石可镂。)

原文地址：http://www.galloway.me.uk/2012/10/a-look-inside-blocks-episode-1/一篇不错的文章地址：http://blog.youkuaiyun.com/wildfireli/article/details/22063001Today I have been taking a look at the internals of how bloc...

Thread Safety SummaryThis appendix describes the high-level thread safety of some key frameworks in OS X and iOS. The information in this appendix is subject to change.CocoaGuidelines for

原英文地址：http://blog.youkuaiyun.com/leikezhu1981/article/details/45535329A timer object can be registered in only one run loop at a time, although it can be added to multiple run loop modes within that run