I want to tell you a story.
我想給大家講個故事。
No, not the story of how, in 1991, Linus Torvalds wrote the first version of the Linux kernel. You can read that story in lots of Linux books. Nor am I going to tell you the story of how, some years earlier, Richard Stallman began the GNU Project to create a free Unix-like operating system. That’s an important story too, but most other Linux books have that one, as well.
故事內容不是 Linus Torvalds 在1991年怎樣寫了 Linux 核心的第一個版本， 因為這些內容你可以在許多 Linux 書籍中讀到。我也不是來告訴你，更早之前，Richard Stallman 是如何開始 GNU 專案，設計了一個免費的類別Unix 的作業系統。那也是一個很有意義的故事， 但大多數 Linux 書籍也講到了它。
No, I want to tell you the story of how you can take back control of your computer.
我想告訴大家一個你如何才能奪回計算機管理權的故事。
When I began working with computers as a college student in the late 1970s, there was a revolution going on. The invention of the microprocessor had made it possible for ordinary people like you and me to actually own a computer. It’s hard for many people today to imagine what the world was like when only big business and big government ran all the computers. Let's just say, you couldn’t get much done.
在20世紀70年代末，我剛開始和計算機打交道時，正進行著一場革命，那時的我還是一名大學生。 微處理器的發明，使普通老百姓（就如你和我）真正擁有一臺計算機成為可能。今天， 人們難以想象，只有大企業和強大的政府才能夠擁有計算機的世界，是怎樣的一個世界。 簡單說，你做不了多少事情。
Today, the world is very different. Computers are everywhere, from tiny wristwatches to giant data centers to everything in between. In addition to ubiquitous computers, we also have a ubiquitous network connecting them together. This has created a wondrous new age of personal empowerment and creative freedom, but over the last couple of decades something else has been happening. A single giant corporation has been imposing its control over most of the world’s computers and deciding what you can and cannot do with them. Fortunately, people from all over the world are doing something about it. They are fighting to maintain control of their computers by writing their own software. They are building Linux.
今天，世界已經截然不同了。計算機遍佈各個領域，從小手錶到大型資料中心，及大小介於它們之間的每件東西。 除了隨處可見的計算機之外，我們還有一個無處不在的連線所有計算機的網路。這已經開創了一個奇妙的， 個人授權和創作自由的新時代，但是在過去的二三十年裡，正在發生另一些事情。一個大公司不斷地把它的 管理權強加到世界上絕大多數的計算機上，並且決定你對計算機的操作權力。幸運地是，來自世界各地的人們， 正積極努力地做些事情來改變這種境況。透過編寫自己的軟體，他們一直在為維護電腦的管理權而戰鬥著。 他們建設著 Linux。
Many people speak of “freedom” with regard to Linux, but I don’t think most people know what this freedom really means. Freedom is the power to decide what your computer does, and the only way to have this freedom is to know what your computer is doing. Freedom is a computer that is without secrets, one where everything can be known if you care enough to find out.
一提到 Linux，許多人都會說到“自由”，但我不認為他們都知道“自由”的真正涵義。“自由”是一種權力， 它決定你的計算機能做什麼，同時能夠擁有這種“自由”的唯一方式就是知道計算機正在做什麼。 “自由”是指一臺沒有任何祕密的計算機，你可以從它那裡瞭解一切，只要你用心的去尋找。
Have you ever noticed in the movies when the “super hacker,”— you know, the guy who can break into the ultra-secure military computer in under thirty seconds —sits down at the computer, he never touches a mouse? It’s because movie makers realize that we, as human beings, instinctively know the only way to really get anything done on a computer is by typing on a keyboard.
你是否注意到，在電影中一個“超級黑客”坐在電腦前，從不摸一下滑鼠， 就能夠在30秒內侵入到超安全的軍用計算機中。這是因為電影製片人意識到， 作為人類，本能地知道讓計算機圓滿完成工作的唯一途徑，是用鍵盤來操縱計算機。
Most computer users today are only familiar with the graphical user interface (GUI) and have been taught by vendors and pundits that the command line interface (CLI) is a terrifying thing of the past. This is unfortunate, because a good command line interface is a marvelously expressive way of communicating with a computer in much the same way the written word is for human beings. It’s been said that “graphical user interfaces make easy tasks easy, while command line interfaces make difficult tasks possible” and this is still very true today.
現在，大多數的計算機使用者只是熟悉圖形使用者介面（GUI），並且產品供應商和此領域的學者會灌輸給使用者這樣的思想， 命令列介面（CLI）是過去使用的一種很恐怖的東西。這就很不幸，因為一個好的命令列介面， 是用來和計算機進行交流溝通的非常有效的方式，正像人類社會使用文字互通訊息一樣。人們說，“圖形使用者介面讓簡單的任務更容易完成， 而命令列介面使完成複雜的任務成為可能”，到現在這句話仍然很正確。
Since Linux is modeled after the Unix family of operating systems, it shares the same rich heritage of command line tools as Unix. Unix came into prominence during the early 1980s (although it was first developed a decade earlier), before the widespread adoption of the graphical user interface and, as a result, developed an extensive command line interface instead. In fact, one of the strongest reasons early adopters of Linux chose it over, say, Windows NT was the powerful command line interface which made the “difficult tasks possible.”
因為 Linux 是以 Unix 家族的作業系統為模型寫成的，所以它分享了 Unix 豐富的命令列工具。 Unix 在20世紀80年代初顯赫一時(雖然，開發它在更早之前），結果，在普遍地使用圖形介面之前， 開發了一種廣泛的命令列介面。事實上，很多人選擇 Linux（而不是其他的系統，比如說 Windows NT）是因為其可以使“完成複雜的任務成為可能”的強大的命令列介面。
This book is a broad overview of “living” on the Linux command line. Unlike some books that concentrate on just a single program, such as the shell program, bash, this book will try to convey how to get along with the command line interface in a larger sense. How does it all work? What can it do? What’s the best way to use it?
這本書介紹如何生存在 Linux 命令列的世界。不像一些書籍僅僅涉及一個程式，比如像 shell 程式，bash。 這本書將試著向你傳授如何與命令列介面友好相處。 它是怎樣工作的？ 它能做什麼？ 使用它的最好方法是什麼？
This is not a book about Linux system administration. While any serious discussion of the command line will invariably lead to system administration topics, this book only touches on a few administration issues. It will, however, prepare the reader for additional study by providing a solid foundation in the use of the command line, an essential tool for any serious system administration task.
這不是一本關於 Linux 系統管理的書。然而任何一個關於命令列的深入討論，都一定會牽涉到 系統管理方面的內容，這本書僅僅提到一點管理方面的知識。但是這本書為讀者準備好了學習更多內容的堅實基礎， 畢竟要勝任系統管理工作也需要良好的命令列使用基本功。
This book is very Linux-centric. Many other books try to broaden their appeal by including other platforms such as generic Unix and MacOS X. In doing so, they “water down” their content to feature only general topics. This book, on the other hand, only covers contemporary Linux distributions. Ninety-five percent of the content is useful for users of other Unix-like systems, but this book is highly targeted at the modern Linux command line user.
這本書是圍繞 Linux 而寫的。許多書籍，為了擴大自身的影響力，會包含一些其它平臺的知識， 比如 Unix, MacOS X 等。這樣做，很多內容只能比較空泛的去講了。另一方面， 這本書只研究了當代 Linux 發行版。雖然，對於使用其它類別 Unix 系統的使用者來說， 書中95％的內容是有用的，但這本書主要面向的物件是現代 Linux 命令列使用者。
This book is for new Linux users who have migrated from other platforms. Most likely you are a “power user” of some version of Microsoft Windows. Perhaps your boss has told you to administer a Linux server, or maybe you’re just a desktop user who is tired of all the security problems and want to give Linux a try. That’s fine.here.All are welcome
這本書是為已經從其它平臺移民到 Linux 系統的新手而寫的。最有可能，你是使用某個 Windows 版本的高手。 或許是老闆讓你去管理一個 Linux 伺服器，或許你只是一個桌面使用者，厭倦了系統出現的各種 安全防禦問題，而想要體驗一下 Linux。很好，這裡歡迎你們！
That being said, there is no shortcut to Linux enlightenment. Learning the command line is challenging and takes real effort. It’s not that it’s so hard, but rather it’s so vast. The average Linux system has literally thousands of programs you can employ on the command line. Consider yourself warned; learning the command line is not a casual endeavor.
不過一般來說，對於 Linux 的啟蒙教育，沒有捷徑可言。學習命令列富於挑戰性，而且很費氣力。 這並不是說 Linux 命令列很難學，而是它的知識量很大，不容易掌握。Linux 作業系統， 差不多有數以千計的命令可供使用者操作。由此可見，要給自己提個醒，命令列可不是輕輕鬆鬆就能學好的。
On the other hand, learning the Linux command line is extremely rewarding. If you think you’re a “power user” now, just wait. You don’t know what real power is — yet. And, unlike many other computer skills, knowledge of the command line is long lasting. The skills learned today will still be useful ten years from now. The command line has survived the test of time.
另一方面，學習 Linux 命令列會讓你受益匪淺，給你極大的回報。如果你認為， 現在你已經是高手了。別急，其實你還不知道什麼才是真正的高手。不像其他一些計算機技能， 一段時間之後可能就被淘汰了，命令列知識卻不會落伍，你今天所學到的，在十年以後， 都會有用處。命令列通過了時間的考驗。
It is also assumed that you have no programming experience, but not to worry, we’ll start you down that path as well.
如果你沒有程式設計經驗，也不要擔心，我會帶你入門。
This material is presented in a carefully chosen sequence, much like a tutor sitting next to you guiding you along. Many authors treat this material in a “systematic” fashion, which makes sense from a writer’s perspective, but can be very confusing to new users.
這些材料是經過精心安排的，很像一位老師坐在你身旁，耐心地指導你。 許多作者用系統化的方式講解這些材料，雖然從一個作者的角度考慮很有道理，但對於 Linux 新手來說， 他們可能會感到非常困惑。
Another goal is to acquaint you with the Unix way of thinking, which is different from the Windows way of thinking. Along the way, we’ll go on a few side trips to help you understand why certain things work the way they do and how they got that way. Linux is not just a piece of software, it’s also a small part of the larger Unix culture, which has its own language and history. I might throw in a rant or two, as well.
另一個目的，是想讓讀者熟悉 Unix 的思維方式，這種思維方式與 Windows 不同。在學習過程中， 我們會幫助你理解為什麼某些命令那樣工作，以及它們是如何工作的。 Linux 不僅是一款軟體，也是 Unix 文化的一小部分，它有自己的語言和歷史淵源。 同時，我也許會說些過激的話。
This book is divided into five parts, each covering some aspect of the command line experience. Besides the first part, which you are reading now, this book contains:
這本書共分為五部分，每一部分講述了不同方面的命令列知識。除了第一部分， 也就是你正在閱讀的這一部分，這本書還包括：
Part 2 – Learning The Shell starts our exploration of the basic language of the command line including such things as the structure of commands, file system navigation, command line editing, and finding help and documentation for commands.
Part 3 – Configuration And The Environment covers editing configuration files that control the computer’s operation from the command line.
Part 4 – Common Tasks And Essential Tools explores many of the ordinary tasks that are commonly performed from the command line. Unix-like operating systems, such as Linux, contain many “classic” command line programs that are used to perform powerful operations on data.
Part 5 – Writing Shell Scripts introduces shell programming, an admittedly rudimentary, but easy to learn, technique for automating many common computing tasks. By learning shell programming, you will become familiar with concepts that can be applied to many other programming languages.
第二部分 — 學習 shell 開始探究命令列基本語言，包括命令組成結構， 檔案系統瀏覽，編寫命令列，查詢命令幫助文件。
第三部分 — 配置檔案及環境 講述瞭如何編寫配置檔案，透過配置檔案，用命令列來 操控計算機。
第四部分 — 常見任務及主要工具 探究了許多命令列經常執行的普通任務。類似於 Unix 的作業系統，例如 Linux, 包括許多經典的命令列程式，這些程式可以用來對資料進行 強大的操作。
第五部分 — 編寫 Shell 指令碼 介紹了 shell 程式設計，一個無可否認的基本技能，能夠自動化許多 常見的計算任務，很容易學。透過學習 shell 程式設計，你會逐漸熟悉一些關於程式語言方面的概念， 這些概念也適用於其他的程式語言。
Start at the beginning of the book and follow it to the end. It isn’t written as a reference work, it’s really more like a story with a beginning, middle, and an end.
從頭到尾的閱讀。它並不是一本技術參考手冊，實際上它更像一本故事書，有開頭，過程，結尾。
To use this book, all you will need is a working Linux installation. You can get this in one of two ways:
為了使用這本書，你需要安裝 Linux 作業系統。你可以透過兩種方式，來完成安裝。
Install Linux on a (not so new) computer. It doesn’t matter which distribution you choose, though most people today start out with either Ubuntu, Fedora, or . If in doubt, try Ubuntu first. Installing a modern Linux distribution can be ridiculously easy or ridiculously difficult depending on your hardware. I suggest a desktop computer that is a couple of years old and has at least 256 megabytes of RAM and 6 gigabytes of free hard disk space. Avoid laptops and wireless networks if at all possible, as these are often more difficult to get working.
Use a “Live CD.” One of the cool things you can do with many Linux distributions is run them directly from a CDROM without installing them at all. Just go into your BIOS setup and set your computer to “Boot from CDROM,” insert the live CD, and reboot. Using a live CD is a great way to test a computer for Linux compatibility prior to installation. The disadvantage of using a live CD is that it may be very slow compared to having Linux installed on your hard drive. Both Ubuntu and Fedora (among others) have live CD versions.
在一臺（不用很新）的電腦上安裝 Linux。你選擇哪個 Linux 發行版安裝，是無關緊要的事。 雖然大多數人一開始選擇安裝 Ubuntu, Fedora, 或者 OpenSUSE。如果你拿不定主意，那就先試試 Ubuntu。 由於主機硬體配置不同，安裝 Linux 時，你可能不費吹灰之力就裝上了，也可能費了九牛二虎之力還裝不上。 所以我建議，一臺使用了幾年的桌上型電腦，至少要有256M 的記憶體，6G 的硬碟可用空間。儘可能避免使用 膝上型電腦和無線網路，在 Linux 環境下，它們經常不能工作。
使用“Live CD.” 許多 Linux 發行版都自帶一個比較酷的功能，你可以直接從系統安裝盤 CDROM 中執行 Linux， 而不必安裝 Linux。開機進入 BIOS 設定介面，更改引導項，設定為“從 CDROM 啟動”。
Regardless of how you install Linux, you will need to have occasional superuser (i.e., administrative) privileges to carry out the lessons in this book.
不管你怎樣安裝 Linux，為了練習書中介紹的知識，你需要有超級使用者（管理員）許可權。
After you have a working installation, start reading and follow along with your own computer. Most of the material in this book is “hands on,” so sit down and get typing!
當你在自己的電腦上安裝了 Linux 系統之後，就開始一邊閱讀本書，一邊練習吧。本書大部分內容 都可以自己動手練習，坐下來，敲入命令，體驗一下吧。
Why I Don’t Call It “GNU/Linux”
In some quarters, it’s politically correct to call the Linux operating system the “GNU/Linux operating system.” The problem with “Linux” is that there is no completely correct way to name it because it was written by many different people in a vast, distributed development effort. Technically speaking, Linux is the name of the operating system’s kernel, nothing more. The kernel is very important of course, since it makes the operating system go, but it’s not enough to form a complete operating system.
Enter Richard Stallman, the genius-philosopher who founded the Free Software movement, started the Free Software Foundation, formed the GNU Project, wrote the first version of the GNU C Compiler (gcc), created the GNU General Public License (the GPL), etc., etc., etc. He insists that you call it “GNU/Linux” to properly reflect the contributions of the GNU Project. While the GNU Project predates the Linux kernel, and the project’s contributions are extremely deserving of recognition, placing them in the name is unfair to everyone else who made significant contributions. Besides, I think “Linux/GNU” would be more technically accurate since the kernel boots first and everything else runs on top of it.
In popular usage, “Linux” refers to the kernel and all the other free and open source software found in the typical Linux distribution; that is, the entire Linux ecosystem, not just the GNU components. The operating system marketplace seems to prefer one-word names such as DOS, Windows, MacOS, Solaris, Irix, AIX. I have chosen to use the popular format. If, however, you prefer to use “GNU/Linux” instead, please perform a mental search and replace while reading this book. I won’t mind.
為什麼我不叫它“GNU/Linux”
在某些領域，把 Linux 作業系統稱為“GNU/Linux 作業系統”， 則政治立場正確。但“Linux”的問題是， 沒有一個完全正確的方式能命名它，因為它是由許許多多，分佈在世界各地的貢獻者們，合作開發而成的。 從技術層面講，Linux 只是作業系統的核心名字，沒別的含義。當然核心非常重要，因為有它， 作業系統才能執行起來，但它並不能構成一個完備的作業系統。
Richard Stallman 是一個天才的哲學家，自由軟體運動創始人，自由軟體基金會創辦者，他建立了 GNU 工程， 編寫了第一版 GNU C 編譯器（gcc），創立了 GNU 通用公共協議（the GPL)等等。 他堅持把 Linux 稱為“GNU/Linux”，為的是準確地反映 GNU 工程對 Linux 作業系統的貢獻。 然而，儘管 GNU 專案早於 Linux 核心，專案的貢獻應該得到極高的讚譽，但是把 GNU 用在 Linux 名字裡， 這對其他為 Linux 的發展做出重大貢獻的程式設計師來說，就不公平了。而且，我覺得要是叫也要叫 “Linux/GNU” 比較準確一些， 因為核心會先啟動，其他一切都執行在核心之上。
在目前流行的用法中，“Linux”指的是核心以及在一個典型的 Linux 發行版中所包含的所有免費及開源軟體； 也就是說，整個 Linux 生態系統，不只有 GNU 專案軟體。在作業系統商界，好像喜歡使用單個詞的名字， 比如說 DOS, Windows, MacOS, Solaris, Irix, AIX. 所以我選擇用流行的命名規則。然而， 如果你喜歡用“GNU/Linux”，當你讀這本書時，可以在腦子裡搜尋並替換“Linux”。我不介意。
Here are some Wikipedia articles on the famous people mentioned in this chapter:
Wikipedia 網站上有些介紹本章提到的名人的文章，以下是連結地址：
The Free Software Foundation and the GNU Project:
介紹自由軟體基金會及 GNU 專案的網站和文章：
Richard Stallman has written extensively on the “GNU/Linux” naming issue:
Richard Stallman 用了大量的文字來敘述“GNU/Linux”的命名問題，可以瀏覽以下網頁：