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The key to Terminal wisdom is the man command. It summons manual (or man) pages for almost any command; they’re the equivalent of a help system for the command line. In fact, man itself is a. An A-Z Index of the Apple macOS command line. Chroot Run a command with a different root directory cksum Print CRC checksum and byte counts clear Clear terminal screen cmp Compare two files comm Compare two sorted files line by line command Run a command. “Mac OS X is a rock-solid system that's beautifully designed.
OS X's command line and I have never been what I'd call 'friendly'; rather, we have a mutual respect and understanding about not messing with each other. (Well, as much of a mutual respect as one can have between a human being and a code window.)
While the average person should never have any reason to visit Terminal, Apple's command line interface app actually does give you access to quite a few neat tricks and shortcuts.. if you're willing to take a peek.
What is Terminal?
Apple's Terminal app is a direct interface to OS X's bash shell — part of its UNIX underpinnings. When you open it, Terminal presents you with a white text screen, logged in with your OS X user account by default.
Here's the important part: With a system administrator account and password, you have direct access to tweaking almost everything about your computer's software code; that means that while this little window provides great power, it comes with great responsibility. In short, be careful before using Terminal to execute commands, and make sure you understand what you're typing.
You can also use Terminal to securely connect to other machines, web servers, and even create your own scripts, but those are how-tos for another day. For now, we're going to focus on using Terminal to explore your own computer.
Basic Terminal commands you should know
Before we get started with the fun stuff, let's learn some basic Terminal terminology and commands. These form the framework for more complex interactions (aka, the fun stuff).
How to execute a Terminal command
You can type something in the Terminal window until you're blue in the face, but it won't execute until you press the Return key on your keyboard. At that point, it will either return an error if you've typed something incorrectly, or the command will execute.
Unless you're executing a command that requires the display of text in Terminal, you won't have any indicator that what you've done has been successful; you'll just get a new line with your user name on it once the command is finished processing.
When writing commands and paths in Terminal, almost everything is case sensitive: This means that you need to remember to properly capitalize 'Dock' when referring to the Dock, or OS X won't understand your command.
What's a path?
You can use Terminal to get direct access to your files without using the Finder. To do so, you build something called a path. Paths look similar in some ways to website sub-directories, and follow the structure of your folders.
Paths take two forms: absolute paths and relative paths. An absolute path starts at the root level of your hard drive, and is displayed as '/'. So if you wanted to make a path to your Applications folder, you would write '/Applications/'.
Relative paths are defined based on where you've already navigated to, and represented by './'. For instance, if you go to the '/Applications/' folder in Terminal, that's your current working directory (cwd). You can then get to your Utilities folder by typing './Utilities/' rather than '/Applications/Utilities'.
When you first launch Terminal, you're starting in the current working directory of /Users/myusername/ (also known as your User folder).
How to display and move between files in Terminal
To actually put all this path knowledge to use, you'll need the Terminal commands for displaying and changing files.
ls: The 'ls' command, by itself, displays the contents of the cwd. So if I were just to type 'ls' in Terminal, it would display the contents of my user directory:
You can optionally add an absolute or relative or path if you want to view a different directories. So, for example, if I wanted to view the Utilities folder inside Applications, I could type 'ls /Applications/Utilities/'. This won't change your current working directory, but it'll let you view other directories on your hard drive.
You can add options to view more information about that directory. The options for 'ls' include:
cd: Where the 'ls' command lets you view a directory, the 'cd' command will actually move to that directory (change your cwd). For instance, if after viewing the Utilities folder, you want to move to it, you'd type 'cd /Applications/Utilities/'.
pwd: Write this command by itself to help you remember the path of your current directory. When typed into terminal, it will print the full path of your cwd.
man: This command, followed by another Unix command, lets you read the Unix manual about the second command. This is super useful if you want to try a cool Terminal trick you found online, but aren't sure what those commands actually do.
For instance, typing 'man ls' will get you information on the 'ls' command, which lists directory contents. Dashlane manual sync on mac download.
How to modify files, folders, and preferences in Terminal
defaults: This command is often used in Terminal tips and tricks to tweak applications and system settings via their preference files. You can use it to do things like disable transparency in the menu bar, always show your scroll bars, change trackpad behavior, and much much more. You'll usually see this paired with either 'write' and a string, as with this:
The code above lets you save all your screenshots as JPGs instead of the system default PNG.
killall: If you execute a Terminal command that affects any system process or app, you're going to need to reboot the process to make it take effect. 'killall' followed by the process will do so. (This is also another way to force quit misbehaving apps or processes if your Force Quit menu isn't behaving.) Remember, this command and its target are case sensitive.
ln: OS X has long offered aliases, which let you create links to files, folders, and applications elsewhere in the system without having to duplicate them. Unfortunately, certain apps don't play well with aliases. With the link command 'ln -s', you can create a low-level, UNIX-based symbolic link which most system processes will recognize. Likely, you'll never have to make a symbolic link, but on the off-chance you want to perform a Terminal trick that requires them, this is how you do it.
The first path listed is your original file's path; the second path is where you'd like your symbolic link.
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chflags: This commands lets you view and change the flags on a file or folder. For most people, the only flags you're going to care about are 'hidden' and 'nohidden', which hide and unhide documents, respectively.
sudo: If you spend any time online, you've probably heard of 'sudo' before. This is Unix's override command, and lets you execute any command as an administrator — provided, of course, that you have the requisite password and permissions. It probably goes without saying, but as a Terminal beginner, it's generally a good idea not to mess with commands like 'sudo' unless you are 100 percent sure what you're doing.
How to use Terminal for fun and whimsy
say: Feeling lonely? You can make your computer say anything you like with the 'say' command, and you can even record it in audio format to your desktop, if you so choose.
telnet towel.blinkenlights.nl: This isn't technically something local to your Mac, but it's my all-time favorite Terminal trick. Some kind soul on the internet made an all-ASCII version of Star Wars: A New Hope; run the following code, and you'll be treated to a full showing. If it doesn't make you smile just a little bit, you might be dead inside.
macOSMainMac Terminal For Command Manual Free
If you’ve read Macworld for any length of time—particularly our OS X Hints blog or any other story that asks you to use Terminal—you may have wondered to yourself: How do you learn about all those mysterious commands, such as
ls or cd ? Is it some kind of arcane knowledge, handed down only to initiates after grueling initiations? Well, no. Actually, anyone can learn about Terminal commands, if they know where to look. Today, I’ll tell you where.
Man up
The key to Terminal wisdom is the
man command. It summons manual (or man) pages for almost any command; they’re the equivalent of a help system for the command line. In fact, man itself is a command, whose role is to format and display this documentation.
First, launch Terminal (in your /Applications/Utilities folder). Then, if you type
man pwd , for example, Terminal will display the man page for the pwd command.
All
man pages have a common format. They begin with name (the name of the command) and a brief description of what it does. The pwd command I looked at above shows the following:
pwd—return working directory name
Next comes synopsis, which shows the command any any options, or flags, that you can use with it. For
pwd , there are two options: -L and -P . These options are explained in the description section:
As you can see here, each of the two options is explained, and a final sentence tells you that the command assumes that the
-L option is desired if no other option (and there’s only one) is specified.
As you work from the command line, you’ll find that reading up on the options available for different commands is really important. You’ll learn the myriad ways you can use these tools, and some
man pages also contain examples to help you understand them.
Mac Terminal For Command Manual 1Paging man pages
When you look at a
man page, you do so in Terminal through another command, called a pager; by default, this is the less command. What a pager does is allow you to view content in Terminal page by page, or line by line. When you’re viewing a man page, you will most often not see the entire page at once. You’ll need to page down to see more.
There are two ways to do this with
less . If you press Return, the page will move down one line. And if you press the spacebar, the page will scroll one page (the number of lines visible in your Terminal window). You can tell that there’s more to come by the : (colon) visible at the bottom of the window.
Try it on your Mac: Open Terminal, type
man ls , then press Return. The ls command’s man page is quite long, and you’ll need to press the spacebar several times to get to the bottom.
Sometimes, when you’re viewing a
man page, you need to go back up and look at something that’s no longer visible. Depending on your Terminal settings, you may be able to scroll the Terminal window. If not, press Control-B to go back a page, and the spacebar, or Control-F, to go forward a page.
When you get to the end of a
man page, you’ll see this: (END) . You’ll notice that you can’t do anything at that point; you need to quit the less command; do this by pressing the q key.
Other ways to read man pages
If you don’t want to read
man pages in Terminal, there are other ways to view this content. Carl Lindberg’s free ManOpen is a simple app that lets you view man pages in a more attractive way than in Terminal. Press Command-O, enter the name of a command, and click Open. ManOpen is especially useful because you can choose specific sections to view from a popup menu, and you can navigate more easily than in Terminal with the less command.
But you can also find
man pages on the Web. Just type man and the name of a command into your favorite search engine, and you’ll get plenty of hits. Apple has a documentation repository with man pages here. You can click Alphabetic Index to get a list of all commands, then search for the one you want. Apple’s man pages are useful because a popup menu near the top of the page lets you choose an OS X version, so if you need to see the man page for an older version of OS X, you can do so.
No matter which route you choose,
man pages open the door to a goldmine of information about the command line. Use them and you’ll learn all the ins and outs of the commands you use.
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