OS X File Sharing — The Basics - Enabling File Sharing

One of the great things about computers these days is that it's so easy to share things among them.  Text documents, music files, photos... anything that lives on your computer can be moved to another device.  Whereas this used to be a semi-complicated procedure for the novice, it's now as easy as finding a checkbox and clicking it.  Mostly.


The procedure goes like this:
•  Enable File Sharing
•  Tell OS X who can file share with your computer
•  Tell OS X what kind of permissions those people have


The important thing to remember when file sharing with OS X (or any computer really), is that there are two distinct devices: the server and the client.  If you are connecting to a computer to take files off of it, you are the client.  If someone else is connecting to your computer, your computer is acting as a server.  Makes sense.


However, if you connect to a computer through file sharing, you can not only take files from that computer, but you can also put files onto that computer.  As long as you have the proper credentials, you can move files, delete files and copy files from the computer you connect to.


So how do you do it?


Well, let's start by setting your computer up to share files, so that you can gain a better understanding of what's involved in the process.


First, head over to the System Preferences, and click the Sharing preference, as seen here:

Once opened, you will see the following screen:

On the left side of this screen, you will see different "sharing" services that you can turn on and off, simply by checking the box next to it.  In the above picture, File Sharing is highlighted and enabled.  


You will see that over to the right of the screen, there is a list of users.  This panel is where you select the people that are allowed to connect to your computer, and what they are allowed to do.


You can allow anyone to connect to your computer, a group of people or individual users, and assign each of them different permissions.  They will be able to either:


1)  Read Only - not only see things on your computer, but also copy things from it.  Others will not be able to modify files on your computer, however.  This is the safest option if you want to share files with others, but you want to make sure that they don't change things by mistake.  If you are at work, your administrator is probably giving you "read-only access" so that you can't mess anything up.
2)  Write Only - copy things to your computer, AND modify items/files/etc.  Other users can leave files for you, but they won't be able to see anything on your computer.  This is handy if you want to provide a simple folder for others to drop files into.  They won't be able to access any other parts of your system.  A write-only folder is often times called a dropbox.
3)  Read & Write - copy things to and from your computer, as well as see files and modify them.  This should be used only if you completely trust the person on the other end, as they will have full access to whatever it is you are giving them permission to (in this case, your whole computer).


So, as you can see, there are many different options to choose from.  For now, we are only going to concern ourselves with one user (you) and one kind of permission (Read & Write).  The beauty of doing things this way is that you are only trusting yourself with the files on your computer.  If you want to add more people in the future, you can just follow these instructions, substituting other accounts for yours.


Let's enable file sharing for your User Account.  To do so, make sure File Sharing is enabled, and then click the "+" sign underneath the list of users.  You will be presented with a new drop-down menu:

As you can see, my user is greyed-out because my user account is already setup for file sharing.

Click on your user account (probably your name), click the Select button, and your user account will be added to the list of accepted users on the right.


Next, it's time to set what permissions your account can have.  Next to your name (which has now been added to the right side pane), click the black arrows.  You will see the following:

Select "Read & Write", and you're done!


Once you've set this up once, you don't need to do it again.  You can enable and disable File Sharing by clicking the checkbox, and OS X will remember who has access to your system.  If you need to remove a user from File Sharing, simply highlight their name on the right, and click the "-" symbol below it.


You will now be able to see your computer on a network, and you can connect to this computer by using your User Account name and password.  Once connected, you will be able to see all of the files on your computer, as well as copy files to your computer and modify things.

The Heart of it All - System Preferences in OS X

Ok, you're running OS X Lion.  Awesome!  Let's hop over to the System Preferences and get acquainted with your computer.  There are a few different ways to get there, but let's start out with a way that might not be entirely obvious, but is completely ubiquitous - the Apple Menu!


Look up in the upper left-hand corner of your screen, and click on the Apple.  Your Apple might be blue, but we can change that through manipulating — you guessed it — your System Preferences.

When you click on System Preferences, you will be presented with the following screen:

This is the heart of your computer, more or less.  From here, you can do all sorts of things like turn on file sharing, add user accounts to your system and encrypt your hard drive.  Don't worry if your screen doesn't look exactly like this; I've added some things onto my computer to make it more useful, and there's plenty of time to cover that at a later date.  I've also changed the arrangement of the System Preferences to be in alphabetical order (preferences for your preferences... so meta!)  To do this, make sure you are in the System Preferences application (it should say "System Preferences" in the menu bar) and click on "View".  Now, select "Organize Alphabetically" like so:

I find this a much easier way to navigate through the preferences.  I don't have to guess what category someone at Apple saw fit to put Users & Groups in, I just need to remember that U is somewhere near the end of the alphabet.


 We'll cover all of the included Apple preferences in detail, but for now, take a look at General by clicking on the General icon:

You can always find what you are looking for by using the search box in the upper right-hand side of the System Preferences window.  OS X even helps you out by highlighting the icon(s) with a circle, and greying the rest.

The following window will open up:

Experiment with these settings to your heart's content; you're not going to mess anything up.  If you don't like something that you've changed, just go back into the General preference and change it back.  Also, please note that these are preferences.  You don't have to make them just like mine, but in case you're interested, this is how I set up all of my computers.


Two things of interest that you will only find in the General preferences: 


1.  Double-click a window's title bar to minimize

If checked, when you double-click on the title bar of a window, it will "minimize" to your dock.  This helps get windows out of the way temporarily, and they are then instantly recallable from your Dock.  I find this useful from time to time.


2.  Restore windows when quitting and re-opening apps


This is a new feature in Lion.  If enabled, any window that was open when you quit an application will automatically open again when you re-launch that application.  For example, if you are working on a text document in TextEdit and you quit the application while that document is still open (on your screen), the next time you launch TextEdit, that same document will pop up, just like you had never quit the application.  This can be useful, especially if you tend to work on the same documents.  However, if you are wondering why some documents are opening up automatically every time you open certain applications, it's because this option is checked.  If you want to turn this feature off temporarily, hold down the "Option" key on your keyboard, and select Quit from any application's File menu.  You'll notice that instead of "Quit", it now says "Quit and Discard Windows".  The only documents that will open the next time you launch the application are windows that have something savable in them (OS X doesn't want to throw out something that you might need later).


You could also just make sure to close any document you don't want to automatically re-open before you quit the application.  So, if you want three of your five currently open documents to automatically open the next time you use TextEdit (or whatever application), close two of the documents you don't want to open, leave the other three open and quit the program.  The next time you launch the application, you should see those three documents.

Not all applications have been updated to support the "restore windows" feature, so some third-party (read: non-Apple) software might not currently behave as expected.  


Feel free to play around with the General settings, and set up your computer the way you want it!