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translating
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The Linux Filesystem Explained
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======
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Back in 1996 I learned how to install software on my spanking new Linux before really understanding the topography of the filesystem. This turned out to be a problem, not so much for programs, because they would just magically work even though I hadn't a clue of where the actual executable files landed. The problem was the documentation.
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You see, back then, Linux was not the intuitive, user-friendly system it is today. You had to read a lot. You had to know things about the frequency rate of your CRT monitor and the ins and outs of your noisy dial-up modem, among hundreds of other things. I soon realized I would need to spend some time getting a handle on how the directories were organized and what all their exotic names like /etc (not for miscellaneous files), /usr (not for user files), and /*bin *(not a trash can) meant.
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This tutorial will help you get up to speed faster than I did.
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### Structure
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It makes sense to explore the Linux filesystem from a terminal window, not because the author is a grumpy old man and resents new kids and their pretty graphical tools -- although there is some truth to that -- but because a terminal, despite being text-only, has better tools to show the map of Linux's directory tree.
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In fact, that is the name of the first tool you'll install to help you on the way: _tree_. If you are using Ubuntu or Debian, you can do:
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```
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sudo apt install tree
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```
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On Red Hat or Fedora, do:
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```
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sudo dnf install tree
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```
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For SUSE/openSUSE use `zypper`:
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```
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sudo zypper install tree
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```
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For Arch-like distros (Manjaro, Antergos, etc.) use:
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```
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sudo pacman -S tree
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```
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... and so on.
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Once installed, stay in your terminal window and run _tree_ like this:
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```
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tree /
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```
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`The /` in the instruction above refers to the _root_ directory. The root directory is the one from which all other directories branch off from. When you run `tree` and tell it to start with _/_ , you will see the whole directory tree, all directories and all the subdirectories in the whole system, with all their files, fly by.
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If you have been using your system for some time, this may take a while, because, even if you haven't generated many files yourself, a Linux system and its apps are always logging, cacheing, and storing temporal files. The number of entries in the file system can grow quite quickly.
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Don't feel overwhelmed, though. Instead, try this:
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```
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tree -L 1 /
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```
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And you should see what is shown in Figure 1.
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The instruction above can be translated as " _show me only the 1st Level of the directory tree starting at / (root)_ ". The `-L` option tells `tree` how many levels down you want to see.
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Most Linux distributions will show you the same or a very similar layout to what you can see in the image above. This means that even if you feel confused now, master this, and you will have a handle on most, if not all, Linux installations in the whole wide world.
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To get you started on the road to mastery, let's look at what each directory is used for. While we go through each, you can peek at their contents using ls.
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### Directories
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From top to bottom, the directories you are seeing are as follows.
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#### _/bin_
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_/bin_ is the directory that contains _bin_ aries, that is, some of the applications and programs you can run. You will find the _ls_ program mentioned above in this directory, as well as other basic tools for making and removing files and directories, moving them around, and so on. There are more _bin_ directories in other parts of the file system tree, but we'll be talking about those in a minute.
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#### _/boot_
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The _/boot_ directory contains files required for starting your system. Do I have to say this? Okay, I'll say it: **DO NOT TOUCH!**. If you mess up one of the files in here, you may not be able to run your Linux and it is a pain to repair. On the other hand, don't worry too much about destroying your system by accident: you have to have superuser privileges to do that.
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#### _/dev_
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_/dev_ contains _dev_ ice files. Many of these are generated at boot time or even on the fly. For example, if you plug in a new webcam or a USB pendrive into your machine, a new device entry will automagically pop up here.
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#### _/etc_
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_/etc_ is the directory where names start to get confusing. _/etc_ gets its name from the earliest Unixes and it was literally "et cetera" because it was the dumping ground for system files administrators were not sure where else to put.
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Nowadays, it would be more appropriate to say that _etc_ stands for "Everything to configure," as it contains most, if not all system-wide configuration files. For example, the files that contain the name of your system, the users and their passwords, the names of machines on your network and when and where the partitions on your hard disks should be mounted are all in here. Again, if you are new to Linux, it may be best if you don't touch too much in here until you have a better understanding of how things work.
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#### _/home_
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_/home_ is where you will find your users' personal directories. In my case, under _/home_ there are two directories: _/home/paul_ , which contains all my stuff; and _/home/guest_ , in case anybody needs to borrow my computer.
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#### _/lib_
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_/lib_ is where _lib_ raries live. Libraries are files containing code that your applications can use. They contain snippets of code that applications use to draw windows on your desktop, control peripherals, or send files to your hard disk.
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There are more _lib_ directories scattered around the file system, but this one, the one hanging directly off of _/_ is special in that, among other things, it contains the all-important kernel modules. The kernel modules are drivers that make things like your video card, sound card, WiFi, printer, and so on, work.
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#### _/media_
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The _/media_ directory is where external storage will be automatically mounted when you plug it in and try to access it. As opposed to most of the other items on this list, _/media_ does not hail back to 1970s, mainly because inserting and detecting storage (pendrives, USB hard disks, SD cards, external SSDs, etc) on the fly, while a computer is running, is a relatively new thing.
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#### _/mnt_
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The _/mnt_ directory, however, is a bit of remnant from days gone by. This is where you would manually mount storage devices or partitions. It is not used very often nowadays.
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#### _/opt_
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The _/opt_ directory is often where software you compile (that is, you build yourself from source code and do not install from your distribution repositories) sometimes lands. Applications will end up in the _/opt/bin_ directory and libraries in the _/opt/lib_ directory.
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A slight digression: another place where applications and libraries end up in is _/usr/local_ , When software gets installed here, there will also be _/usr/local/bin_ and _/usr/local/lib_ directories. What determines which software goes where is how the developers have configured the files that control the compilation and installation process.
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#### _/proc_
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_/proc_ , like _/dev_ is a virtual directory. It contains information about your computer, such as information about your CPU and the kernel your Linux system is running. As with _/dev_ , the files and directories are generated when your computer starts, or on the fly, as your system is running and things change.
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#### _/root_
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_/root_ is the home directory of the superuser (also known as the "Administrator") of the system. It is separate from the rest of the users' home directories BECAUSE YOU ARE NOT MEANT TO TOUCH IT. Keep your own stuff in you own directories, people.
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#### _/run_
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_/run_ is another new directory. System processes use it to store temporary data for their own nefarious reasons. This is another one of those DO NOT TOUCH folders.
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#### _/sbin_
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_/sbin_ is similar to _/bin_ , but it contains applications that only the superuser (hence the initial _s_ ) will need. You can use these applications with the `sudo` command that temporarily concedes you superuser powers on many distributions. _/sbin_ typically contains tools that can install stuff, delete stuff and format stuff. As you can imagine, some of these instructions are lethal if you use them improperly, so handle with care.
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#### _/usr_
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The _/usr_ directory was where users' home directories were originally kept back in the early days of UNIX. However, now _/home_ is where users kept their stuff as we saw above. These days, _/usr_ contains a mish-mash of directories which in turn contain applications, libraries, documentation, wallpapers, icons and a long list of other stuff that need to be shared by applications and services.
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You will also find _bin_ , _sbin_ and _lib_ directories in _/usr_. What is the difference with their root-hanging cousins? Not much nowadays. Originally, the _/bin_ directory (hanging off of root) would contain very basic commands, like `ls`, `mv` and `rm`; the kind of commands that would come pre-installed in all UNIX/Linux installations, the bare minimum to run and maintain a system. _/usr/bin_ on the other hand would contain stuff the users would install and run to use the system as a work station, things like word processors, web browsers, and other apps.
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But many modern Linux distributions just put everything into _/usr/bin_ and have _/bin_ point to _/usr/bin_ just in case erasing it completely would break something. So, while Debian, Ubuntu and Mint still keep _/bin_ and _/usr/bin_ (and _/sbin_ and _/usr/sbin_ ) separate; others, like Arch and its derivatives just have one "real" directory for binaries, _/usr/bin_ , and the rest or _*bin_ s are "fake" directories that point to _/usr/bin_.
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#### _/srv_
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The _/srv_ directory contains data for servers. If you are running a web server from your Linux box, your HTML files for your sites would go into _/srv/http_ (or _/srv/www_ ). If you were running an FTP server, your files would go into _/srv/ftp_.
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#### _/sys_
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_/sys_ is another virtual directory like _/proc_ and _/dev_ and also contains information from devices connected to your computer.
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In some cases you can also manipulate those devices. I can, for example, change the brightness of the screen of my laptop by modifying the value stored in the _/sys/devices/pci0000:00/0000:00:02.0/drm/card1/card1-eDP-1/intel_backlight/brightness_ file (on your machine you will probably have a different file). But to do that you have to become superuser. The reason for that is, as with so many other virtual directories, messing with the contents and files in _/sys_ can be dangerous and you can trash your system. DO NOT TOUCH until you are sure you know what you are doing.
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#### _/tmp_
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_/tmp_ contains temporary files, usually placed there by applications that you are running. The files and directories often (not always) contain data that an application doesn't need right now, but may need later on. So, to free up RAM, it gets stored here.
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You can also use _/tmp_ to store your own temporary files -- _/tmp_ is one of the few directories hanging of _/_ which you can actually interact with without becoming superuser. The problem is that applications sometimes don't come back to retrieve and delete files and directories and _/tmp_ can often end up eating up space on your hard disk, filling it up with junk. Later on in this series we'll see how to clean it up.
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#### _/var_
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_/var_ was originally given its name because its contents was deemed _variable_ , in that it changed frequently. Today it is a bit of a misnomer because there are many other directories that also contain data that changes frequently, especially the virtual directories we saw above.
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Be that as it may, _/var_ contains things like logs in the _/var/log_ subdirectories. Logs are files that register events that happen on the system. If something fails in the kernel, it will be logged in a file in _/var/log_ ; if someone tries to break into your computer from outside, your firewall will also log the attempt here. It also contains _spools_ for tasks. These "tasks" can be the jobs you send to a shared printer when you have to wait because another user is printing a long document, or mail that is waiting to be delivered to users on the system.
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Your system may have some more directories we haven't mentioned above. In the screenshot, for example, there is a _/snap_ directory. That's because the shot was captured on an Ubuntu system. Ubuntu has recently incorporated [snap][1] packages as a way of distributing software. The _/snap_ directory contains all the files and the software installed from snaps.
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### Digging Deeper
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That is the root directory covered, but many of the subdirectories lead to their own set of files and subdirectories. Figure 2 gives you an overall idea of what the basic file system tree looks like (the image is kindly supplied under a CC By-SA license by Paul Gardner) and [Wikipedia has a break down with a summary of what each directory is used for][2].
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![filesystem][4]
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Figure 2: Standard Unix filesystem hierarchy.
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[Used with permission][5]
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Paul Gardner
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To explore the filesystem yourself, use the `cd` command:
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```
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cd
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```
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will take you to the directory of your choice ( _cd_ stands for _change directory_.
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If you get confused,
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```
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pwd
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```
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will always tell you where you ( _pwd_ stands for _print working directory_ ). Also,
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```
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cd
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```
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with no options or parameters, will take you back to your own home directory, where things are safe and cosy.
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Finally,
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```
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cd ..
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```
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will take you up one level, getting you one level closer to the _/_ root directory. If you are in _/usr/share/wallpapers_ and run `cd ..`, you will move up to _/usr/share_.
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To see what a directory contains, use
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```
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ls
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```
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or simply
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```
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ls
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```
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to list the contents of the directory you are in right now.
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And, of course, you always have `tree` to get an overview of what lays within a directory. Try it on _/usr/share_ \-- there is a lot of interesting stuff in there.
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### Conclusion
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Although there are minor differences between Linux distributions, the layout for their filesystems are mercifully similar. So much so that you could say: once you know one, you know them all. And the best way to know the filesystem is to explore it. So go forth with `tree`, `ls`, and `cd` into uncharted territory.
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You cannot damage your filesystem just by looking at it, so move from one directory to another and take a look around. Soon you'll discover that the Linux filesystem and how it is laid out really makes a lot of sense, and you will intuitively know where to find apps, documentation, and other resources.
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Learn more about Linux through the free ["Introduction to Linux" ][6]course from The Linux Foundation and edX.
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--------------------------------------------------------------------------------
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via: https://www.linux.com/blog/learn/intro-to-linux/2018/4/linux-filesystem-explained
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作者：[PAUL BROWN][a]
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选题：[lujun9972](https://github.com/lujun9972)
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译者：[译者ID](https://github.com/译者ID)
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||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
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本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
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[a]:https://www.linux.com/users/bro66
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[1]:https://www.ubuntu.com/desktop/snappy
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[2]:https://en.wikipedia.org/wiki/Unix_filesystem#Conventional_directory_layout
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[3]:https://www.linux.com/files/images/standard-unix-filesystem-hierarchypng
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[4]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/standard-unix-filesystem-hierarchy.png?itok=CVqmyk6P (filesystem)
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[5]:https://www.linux.com/licenses/category/used-permission
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[6]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
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# Linux文件系统详解
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早在1996年，在真正理解文件系统的结构之前，我就学会了如何在我崭新的 Linux 上安装软件。这是一个问题，但不是程序的问题，因为即使我不知道实际的可执行文件在哪里，它们也会神奇地工作。问题在于文档。
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你看，那时候，Linux 不是像今天这样直观，用户友好的系统。 你必须读很多东西。 你必须知道你的 CRT 显示器的频率以及拨号调制解调器的噪音来龙去脉，以及其他数以百计的事情。 我很快就意识到我需要花一些时间来掌握目录的组织方式以及 /etc（不用于其他文件），/usr（不是用于用户文件）和 /*bin *（ 不是垃圾桶）的意思。
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本教程将帮助您加快速度，比我做得更快。
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### 结构
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从终端窗口探索 Linux 文件系统是有道理的，这并不是因为作者是一个脾气暴躁的老人，并且对新孩子和他们漂亮的图形工具不以为然——尽管有一些事实——但是因为终端，尽管是文本——只有更好的工具才能显示 Linux 目录树的结构。
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事实上，这是您将安装的第一个工具的名称：*tree*。如果你正在使用 Ubuntu 或 Debian ，你可以：
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```
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sudo apt install tree
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```
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在 Red Hat 或 Fedora :
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```
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sudo dnf install tree
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```
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对于 SUSE/openSUSE 可以使用 `zypper`：
|
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|
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```
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sudo zypper install tree
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```
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对于使用 Arch （Manjaro，Antergos，等等）使用：
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```
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sudo pacman -S tree
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|
||||
```
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||||
...等等。
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||||
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||||
一旦安装好，在终端窗口运行 *tree* 命令：
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```
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tree /
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||||
```
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||||
上述指令中的 `/` 指的是根目录。系统中的其他目录都是从根目录分支而出，当你运行 `tree` 命令，并且告诉它从根目录开始，那么你就可以看到整个目录树，系统中的所有目录及其子目录，还有他们的文件。
|
||||
|
||||
如果您已经使用您的系统有一段时间了，这可能需要一段时间，因为即使您自己还没有生成很多文件，Linux系统及其应用程序总是记录、缓存和存储临时文件。文件系统中的条目数量可以快速增长。
|
||||
|
||||
不过，不要感到不知所措。 相反，试试这个：
|
||||
|
||||
```
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||||
tree -L 1 /
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||||
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||||
```
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||||
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||||
您应该看到如图 1 所示。
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||||
|
||||
|
||||
|
||||
上面的指令可以翻译为“只显示以 /（根目录） 开头的目录树的第一级”。 `-L` 选项告诉树你想看到多少层目录。
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||||
|
||||
大多数 Linux 发行版都会向您显示与您在上图中看到的相同或非常类似的结构。 这意味着，即使你现在感到困惑，掌握这一点，你将掌握大部分（如果不是全部的话）整个世界的 Linux 文件系统。
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|
||||
为了让您开始走上掌握之路，让我们看看每个目录的用途。 当我们查看每一个目录的时候，你可以使用 *ls* 来查看他们的内容。
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||||
### 目录
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||||
从上到下，你所看到的目录如下
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||||
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||||
#### _/bin_
|
||||
|
||||
*/bin* 目录是包含一些二进制文件的目录，即可以运行的一些应用程序。 你会在这个目录中找到上面提到的 *ls* 程序，以及用于新建和删除文件和目录，移动它们基本工具。还有其他一些程序，等等， 文件系统树的其他部分有更多的 *bin* 目录，但我们将在一分钟内讨论这些目录。
|
||||
|
||||
#### _/boot_
|
||||
|
||||
*/boot* 目录包含启动系统所需的文件。 我必须要说吗？ 好吧，我会说：**不要动它**！ 如果你在这里弄乱了其中一个文件，你可能无法运行你的 Linux，修复破坏的系统是非常痛苦的一件事。 另一方面，不要太担心无意中破坏系统：您必须拥有超级用户权限才能执行此操作。
|
||||
|
||||
#### _/dev_
|
||||
|
||||
*/dev* 目录包含设备文件。 其中许多是在启动时或甚至在运行时生成的。 例如，如果您将新的网络摄像头或 USB 随身碟连接到您的机器中，则会自动弹出一个新的设备条目。
|
||||
|
||||
#### _/etc_
|
||||
|
||||
*/etc* 的目录名称会让人变得非常的困惑。*/etc* 从最早的 Unixes 系统中得到它的名称，它的字面意思是 “et cetera” ，因为它是系统文件管理员不确定在哪里放置文件的垃圾场。
|
||||
|
||||
现在，说 */etc* 是“要配置的所有内容”更为恰当，因为它包含大部分（如果不是全部的话）系统配置文件。 例如，包含系统名称，用户及其密码，网络上计算机名称以及硬盘上分区的安装位置和时间的文件都在这里。 再说一遍，如果你是 Linux 的新手，最好是不要在这里接触太多，直到你对系统的工作有更好的理解。
|
||||
|
||||
#### _/home_
|
||||
|
||||
*/home* 是您可以找到用户个人目录的地方。 在我的情况下，*/home* 下有两个目录：*/home/paul*，其中包含我所有的东西；另外一个目录是 */home/guest* 目录，以防有人需要使用我的电脑。
|
||||
|
||||
#### _/lib_
|
||||
|
||||
*/lib* 是库文件所在的地方。 库是包含应用程序可以使用的代码文件。 它们包含应用程序用于在桌面上绘制窗口，控制外围设备或将文件发送到硬盘的代码片段。
|
||||
|
||||
在文件系统周围散布着更多的 *lib* 目录，但是这个直接挂载在 / 的 */lib* 目录是特殊的，除此之外，它包含了所有重要的内核模块。 内核模块是使您的视频卡，声卡，WiFi，打印机等工作的驱动程序。
|
||||
|
||||
#### _/media_
|
||||
|
||||
在 */media* 目录中，当您插入外部存储并试图访问它时，将自动挂载它。与此列表中的大多数其他项目不同，*/media* 并不追溯到 1970 年代，主要是因为当计算机正在运行而动态地插入和检测存储（ U 盘, USB 硬盘，SD卡，外部 SSD 等)，这是最近才发生的事。
|
||||
|
||||
#### _/mnt_
|
||||
|
||||
然而，*/mnt* 目录是一些过去的残余。这是您手动挂载存储设备或分区的地方。现在不常用了。
|
||||
|
||||
#### _/opt_
|
||||
|
||||
*/opt* 目录通常是您编译软件（即，您从源代码构建，并不是从您的系统的软件库中安装软件）的地方。应用程序最终会出现在 */opt/bin* 目录，库会在 */opt/lib* 目录中出现。
|
||||
|
||||
稍微的题外话：应用程序和库的另一个地方是 */usr/local*，在这里安装软件时，也会有 */usr/local/bin* 和 */usr/local/lib* 目录。开发人员如何配置文件来控制编译和安装过程，这就决定了软件安装到哪个地方。
|
||||
|
||||
#### _/proc_
|
||||
|
||||
*/proc*，就像 */dev* 是一个虚拟目录。它包含有关您的计算机的信息，例如关于您的 CPU 和您的 Linux 系统正在运行的内核的信息。与 */dev* 一样，文件和目录是在计算机启动或运行时生成的，因为您的系统正在运行且会发生变化。
|
||||
|
||||
#### _/root_
|
||||
|
||||
*/root* 是系统的超级用户（也称为“管理员”）的主目录。 它与其他用户的主目录是分开的，因为您打算去动它。 所以把自己的东西放在你自己的目录中，伙计们。
|
||||
|
||||
#### _/run_
|
||||
|
||||
*/run* 是另一个新目录。系统进程出于自己的邪恶原因使用它来存储临时数据。这是另一个不要动它的文件夹例子。
|
||||
|
||||
#### _/sbin_
|
||||
|
||||
*/sbin* 与 */bin* 类似，但它包含的应用程序只有超级用户（即首字母的 s ）才需要。您可以使用 `sudo` 命令使用这些应用程序，该命令暂时允许您在许多发行版上拥有超级用户权限。*/sbin* 目录通常包含可以安装、删除和格式化内容的工具。你可以想象，如果你使用不当，这些指令中有一些是致命的，所以要小心处理。
|
||||
|
||||
#### _/usr_
|
||||
|
||||
*/usr* 目录是在 UNIX 早期用户的主目录被保留的地方。然而，正如我们上面看到的，现在 */home* 是用户保存他们的东西的地方。如今，*/usr* 包含了大量目录，而这些目录又包含了应用程序、库、文档、壁纸、图标和许多其他需要应用程序和服务共享的内容。
|
||||
|
||||
您还可以在 */usr* 目录下找到 */bin*，*/sbin*，*/lib* 目录，他们与挂载到根目录下的那些有什么区别呢？现在的区别不是很大。在早期，/bin 目录（挂载在根目录下的）只会包含一些基本的命令，例如 *ls*，*mv* 和 *rm* ；这是一些在安装系统的时候就会预装的一些命令，用于维护系统的一个基本的命令。 而 */usr/bin* 目录则包含了用户自己安装和用于工作的软件，例如文字处理器，浏览器和一些其他的软件。
|
||||
|
||||
但是许多现代的 Linux 发行版只是把所有的东西都放到 */usr/bin* 中，并让 */bin* 指向 */usr/bin*，以防彻底删除它会破坏某些东西。因此，Debian、Ubuntu 和 Mint 仍然保持 */bin* 和 */usr/bin* （和 */sbin* 和 */usr/sbin* ）分离；其他的，比如 Arch 和它衍生版，只是有一个二进制的“真实”目录，*/usr/bin*，其余的或 *bin 是指向 */usr/ bin* 的“假”目录。
|
||||
|
||||
#### _/srv_
|
||||
|
||||
*/srv* 目录包含服务器的数据。 如果您正在 Linux 机器上运行 Web 服务器，您网站的 HTML文件将放到 */srv/http*（或 */srv/www*）。 如果您正在运行 FTP 服务器，则您的文件将放到 */srv/ftp*。
|
||||
|
||||
#### _/sys_
|
||||
|
||||
*/sys* 是另一个类似 */proc* 和 */dev* 的虚拟目录，它还包含连接到计算机的设备的信息。
|
||||
|
||||
在某些情况下，您还可以操纵这些设备。 例如，我可以通过修改存储在 /sys/devices/pci0000:00/0000:00:02.0/drm/card1/card1-eDP-1/intel_backlight/brightness 中的值来更改笔记本电脑屏幕的亮度（在你的机器上你可能会有不同的文件）。但要做到这一点，你必须成为超级用户。原因是，与许多其他虚拟目录一样，在 */sys* 中打乱内容和文件可能是危险的，您可能会破坏系统。直到你确信你知道你在做什么。否则不要动它。
|
||||
|
||||
#### _/tmp_
|
||||
|
||||
*/tmp* 包含临时文件，通常由正在运行的应用程序放置。文件和目录通常（并非总是）包含应用程序现在不需要但以后可能需要的数据。为了释放内存，它被存储在这里。
|
||||
|
||||
您还可以使用 */tmp* 来存储您自己的临时文件—— /tmp 是挂载到根目录下您可以在不成为超级用户的情况下与它进行实际交互少数目录之一。问题是，应用程序有时不会回来检索和删除文件和目录，而且 */tmp* 常常会耗尽硬盘上的空间，使其塞满垃圾。在本系列的后面，我们将看到如何清理它。
|
||||
|
||||
#### _/var_
|
||||
|
||||
*/var* 最初被命名是因为它的内容被认为是可变的，因为它经常变化。今天，它有点用词不当，因为还有许多其他目录也包含频繁更改的数据，特别是我们上面看到的虚拟目录。
|
||||
|
||||
不管怎样，*/var* 目录包含了类似 */var/log* 子目录的日志文件。日志是记录系统中发生的事件的文件。如果内核中出现了什么问题，它将被记录到 */var/log* 文件中；如果有人试图从外部侵入您的计算机，您的防火墙也将记录尝试。它还包含用于任务的假脱机程序。这些“任务”可以是您在不得不等待时发送给共享打印机的任务，因为另一个用户正在打印一个长文档，或者是等待发送给系统上的用户的邮件。
|
||||
|
||||
您的系统可能还有一些我们上面没有提到的目录。例如，在屏幕截图中，有一个 */snap* 目录。这是因为这张截图是在Ubuntu系统上截取的。Ubuntu 最近将 [snap][1] 包作为一种分发软件的方式。*/snap* 目录包含所有文件和从 snaps 安装的软件。
|
||||
|
||||
### 更深入的研究
|
||||
|
||||
这里仅仅谈了根目录，但是许多子目录都指向它们自己的一组文件和子目录。图 2 给出了基本文件系统的总体概念（图片是在 Paul Gardner 的 CC BY-SA 许可下提供的），[Wikipedia 对每个目录的用途进行了总结][2]。
|
||||
|
||||
|
||||
![filesystem][4]
|
||||
|
||||
图 2：标准 Unix 文件系统
|
||||
|
||||
[许可][5]
|
||||
|
||||
Paul Gardner
|
||||
|
||||
要自行探索文件系统，请使用 `cd` 命令:
|
||||
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
将带您到您所选择的目录（ *cd* 代表更改目录）。
|
||||
|
||||
如果你不知道你在哪儿，
|
||||
|
||||
```
|
||||
pwd
|
||||
|
||||
```
|
||||
|
||||
*pwd* 会告诉你，你到底在哪里，（ *pwd* 代表打印工作目录 ），同时
|
||||
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
*cd* 命令在没有任何选项或者参数的时候，将会直接带你到你自己的主目录，这是一个安全舒适的地方。
|
||||
|
||||
最后，
|
||||
|
||||
```
|
||||
cd ..
|
||||
|
||||
```
|
||||
|
||||
*cd ..* 将会带你到上一层目录，会使你更加接近根目录，如果你在 */usr/share/wallpapers* 目录，然后你执行 `cd ..` 命令，你将会跳转到 `/usr/share` 目录
|
||||
|
||||
要查看目录里有什么内容，使用
|
||||
|
||||
```
|
||||
ls
|
||||
|
||||
```
|
||||
|
||||
或这简单的使用
|
||||
|
||||
```
|
||||
l
|
||||
|
||||
```
|
||||
|
||||
列出你所在目录的内容。
|
||||
|
||||
当然，您总是可以使用 `tree` 来获得目录中内容的概述。在 */usr/share* 上试试——里面有很多有趣的东西。
|
||||
|
||||
### 总结
|
||||
|
||||
尽管 Linux 发行版之间存在细微差别，但它们的文件系统的布局非常相似。 你可以这么说：一旦你认识一个，你就会知道他们。 知道文件系统的最好方法就是探索它。 因此，伴随 `tree` ，`ls` 和 `cd` 进入未知的领域吧。
|
||||
|
||||
您不能仅仅通过查看文件系统就破坏文件系统，因此请从一个目录移动到另一个目录并进行浏览。 很快你就会发现 Linux 文件系统及其布局的确很有意义，并且你会直观地知道在哪里可以找到应用程序，文档和其他资源。
|
||||
|
||||
通过 Linux 基金会和 edX 免费的 “[Linux入门][6]” 课程了解更多有关 Linux 的信息。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/learn/intro-to-linux/2018/4/linux-filesystem-explained
|
||||
|
||||
作者：[PAUL BROWN][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[amwps290](https://github.com/amwps290)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/bro66
|
||||
[1]:https://www.ubuntu.com/desktop/snappy
|
||||
[2]:https://en.wikipedia.org/wiki/Unix_filesystem#Conventional_directory_layout
|
||||
[3]:https://www.linux.com/files/images/standard-unix-filesystem-hierarchypng
|
||||
[4]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/standard-unix-filesystem-hierarchy.png?itok=CVqmyk6P "filesystem"
|
||||
[5]:https://www.linux.com/licenses/category/used-permission
|
||||
[6]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
|
||||
Loading…
Reference in New Issue
Block a user