libz.1.2.5.dylib与libz.1.2.5.tbd

 libz.1.2.5.dylib(Xcode 4.5) 

libz.dylib 更名为libz.1.2.5.tbd

官方文档

 

A file ending in the extension  .dylib  is a dynamic library: it's a library that's loaded at runtime instead of at compile time. If you're familiar with DLLs from Windows or DSOs, it's more or less the same type of thing with a few twists. The Dynamic Library Programming Topics  section of the Mac OS X Developer Library covers all the details about the format and what you should be aware of.

libz.dylib  is the dynamic library for  Zlib , a general compression library. PDFs can (and usually do) use zlib to compress different aspects of the data contained within them, but accessing the PDF data at that level is pretty low-level, and higher-level libraries would abstract most of that type of stuff.

扩展文件结束。dylib是一个动态库:这是一个库,在运行时加载,而不是在编译时。如果您熟悉dll从Windows或都是或多或少相同类型的一些曲折。动态库编程的主题部分Mac OS X开发库涵盖所有细节的格式和你应该意识到什么。

libz.dylib Zlib是动态库,一般压缩库。PDF文件(通常)可以使用zlib压缩中包含的数据的不同方面,但访问PDF数据水平很低,和高级库将抽象的大多数类型的东西。