请大家放心，这是真正正式版，原版pdf。The Linux Command Line, 2nd Edition: A Complete Introduction 2nd Edition.

In this book, I describe the Linux programming interface—the system calls, library functions, and other low-level interfaces provided by Linux, a free implementation of the UNIX operating system. These interfaces are used, directly or indirectly, by every program that runs on Linux. They allow applications to perform tasks such as file I/O, creating and deleting files and directories, creating new processes, executing programs, setting timers, communicating between processes and threads on the same computer, and communicating between processes residing on different computers connected via a network. This set of low-level interfaces is sometimes also known as the system programming interface. Although I focus on Linux, I give careful attention to standards and portability issues, and clearly distinguish the discussion of Linux-specific details from the discussion of features that are common to most UNIX implementations and standardized by POSIX and the Single UNIX Specification. Thus, this book also provides a comprehensive description of the UNIX/POSIX programming interface and can be used by programmers writing applications targeted at other UNIX systems or intended to be portable across multiple systems.

My primary intent in writing this book is to provide the reader with basic programming, financial, and mathematical tools that can be successfully leveraged both in industry and academia. I cover the use of the R programming language, as well as the R environment as a means for manipulating financial market data and for solving a subset of problems that quants and traders typically encounter in their day-to-day activities. The chapters that follow should be treated as a tutorial on a recommended set of tools that I have personally found useful and that have served me well during the last few years of my career as a quant trader/developer. I am writing this book from the vantage point of a quant practitioner and not that of an academic. A significant portion of the content is based on my lecture notes from a graduate level class in quantitative finance that I teach on a part-time basis at Loyola University in Chicago.

HTML5 Canvas : Native Interactivity and Animation for the Web (英文原版pdf) 2011.5

UML精粹（UML Distilled）第3版，比较难得的英文原版PDF