Chapter 6
In This Chapter
Taking advantage of multiuser sharing
Setting and changing permissions
Sharing documents in Microsoft Office 2011 for the Mac
Now here’s a topic that any OS X power user can sink his teeth into — the idea that a document on a multiuser system can be everyone’s property, allowing anyone in your family, workgroup, or highly competitive mob to make whatever changes are necessary, whenever they like.
Of course, potential pitfalls lurk — even in the Apple world, there’s no such thing as an operating system that’s both powerful and perfectly simple. However, I think you’ll find that our dear friends from Cupertino have done just about as well as can be expected and that the settings that you use to share documents are fairly easy to understand.
Prepare to share!
First, allow me to clear up what I’ve found to be a common misconception by using another of Mark’s Maxims.
True, multiple users can share a document over a network, which is a topic that I cover in Book VI. But although the results are the same, the way you share that same document on a single machine betwixt multiple users is a completely different turn of the screw. In this section, I discuss the factoids behind the matter.
Although reiterating that no network is required is seemingly the most obvious of statements, many otherwise knowledgeable OS X power users seem to forget that sharing a document over a network requires an active network connection. (Note the word active there.) Unless you physically copy the document to your hard drive — which defeats the purpose of document sharing — any loss of network connectivity or any problem with your network account results in a brick wall and a brightly painted (or flashing neon) sign reading, “No luck, Jack.”
On the other hand, a document shared on a multiuser Mac in the home or classroom is available whenever you need it. As long as the file is located in the Shared folder, the file privileges are set correctly, and you know the password (if one is required by the application, such as a password-protected Word document), you’re set to go, regardless of whether your network connection is active.
Sharing documents over a network can get a tad hairy when multiple users open and edit a document simultaneously. Applications, such as Office 2011 for the Mac, have methods of locking a document (giving one person exclusive access) when someone opens it or saves it. However, you always face the possibility that what you’re seeing in a shared network document isn’t exactly what’s in the document at that moment.
A multiuser system doesn’t need such exquisite complexity. You’re the one sitting at the keyboard, and you have control: This is what network administrators call a guaranteed lock on that document file. Refreshing, isn’t it?
But wait! OS X Yosemite includes a feature called Fast User Switching — I discuss it in Book I, Chapter 2 — that allows other users to remain logged in behind the scenes while another user is at the keyboard. Therefore, if you enable Fast User Switching, two users could have the same document open at the same time on a single Mac. To prevent this, you can simply turn off Fast User Switching from the Users & Groups pane in System Preferences. (Click Users & Groups, click Login Options, and clear the Enable Fast User Switching check box.)
Network users are often confident that they can blithely copy and move a document from one place to another with the greatest of ease, and that’s true. Most shared network documents created by an application — such as a project outline created in Word, for example — carry their own sharing information and document settings internally. Thus, you can move that same file to another folder on your hard drive, and the rest of the network team can still open it — if they have the network rights to access the new folder, of course.
This isn’t the case when it comes to multiuser documents. As you can read in Chapters 4 and 5 of this minibook, OS X places a tight fence around a standard-level user, allowing that person to access only the contents of certain folders. In this case, your document must be placed in the Shared folder for every standard-level user to be able to open it. If everyone using the document has administrator access, you can store the file in other spots on your system; as long as the permissions are set, you’re set. And speaking of permissions … .
Files are shared in OS X according to a set of rules called permissions, the ownership of a file (typically the person who saved the document the first time), and an access level shared by multiple users who are specified as a group. The combination of privileges, ownership, and group determines who can do what with a file.
When you (or the person with the administrator account on your Mac) created your user account, you were automatically granted ownership of your Home folder (which appears in the Sidebar of every Finder window) and everything that it contains, as well as any files or folders that you store in the Shared folder or another user’s Public folder.
Four possible actions are allowed through permissions:
These permissions are set in the Info dialog or Inspector window for a file or folder (always accessible by pressing +I). If you’re setting the permissions for a folder, you can also elect to apply those same settings to all the enclosed items in the folder.
To set permissions, follow these steps:
You can right-click the item and choose Get Info instead. Either way, OS X displays the Info dialog.
This is likely set to Read & Write, and it’s a good idea to leave it alone. If you’re the file’s owner, you’re likely not a security risk.
Perhaps I should be a little less tactful here: Never choose an access level for yourself other than Read & Write without being absolutely sure of what you’re doing because you could prevent yourself from accessing or deleting the file in the future! For example, if you simply want to lock an item to prevent changes being made, don’t set your Ownership permission to Read Only. Instead, select the Locked check box in the General section of the Info dialog instead. You can easily clear the Locked check box later to make changes to the item.
If the Permissions fields in your Info dialog are disabled (they’re dimmed and can’t be clicked), the dialog is locked to prevent accidental changes. To unlock the dialog and make changes, click the tiny padlock icon at the lower-right corner of the Info dialog, type your user password, and then click OK. You can lock an Info dialog also by clicking the padlock icon again.
Assigning permissions for an entire group is a good idea for limiting specific files and folders to only administrator access. (Note, however, that Yosemite reserves the group name wheel — a term from the Unix world that encompasses all administrator accounts — for internal tasks, so never alter any permissions for a group originally created by OS X.)
If a user isn’t the owner of an item and doesn’t fit into any group that you selected, this access permission setting for this file applies to that user.
Need to apply the same permissions to all the contents of a folder — including subfolders within it? Select a folder, click the Action button at the bottom of the Info dialog (which carries a gear icon), and choose Apply to Enclosed Items from the pop-up menu that appears. After you confirm the action, Yosemite automatically changes the permissions for all the items in the folder to the same settings.
Generally, do not override the permissions for all the items in a folder, so use the Apply to Enclosed Items action only when necessary.
If a specific user or group doesn’t appear already in the Privilege list, click the Add button (bearing the plus sign), and you can add a specific privilege level for that user or group. You can also delete a privilege level: Click the desired entry to select it and click the Delete button (which bears a minus sign).
After you get the basics of sharing files and assigning permissions under your belt, you need to master when to change permissions and why you should (and shouldn’t) modify them. Follow these commonsense guidelines when saving documents, assigning permissions, and choosing access levels:
This last one is quite striking for a reason, so heed the warning.
Many OS X applications offer their own built-in document-sharing features. For example, Microsoft Office 2011 for the Mac includes both file-level and document-sharing features. Because Office 2011 is the most popular productivity suite available for OS X, I discuss these commands in this final section.
You’ll find a number of commands that help multiple users keep track of changes that have been made in a shared Office document. Probably the most familiar is the Word revision-tracking feature (heavily used during the development of this book), but there are others as well:
Along with the document-level sharing commands, you’ll find that Office 2011 applications also offer sharing features that control access to the document file itself.
You can add password protection to any Office 2011 document. Follow these steps with a document created in Word, Excel, or PowerPoint:
This password must be provided when opening the document.
If you like, you can enter another password in the Password to Modify field. This second password would then also be required to modify the document.
Both passwords are case-sensitive.
Think of the Protect Document dialog in Word, from which you can effectively write-protect certain elements, as an extra level of security in a multiuser environment. In this Office application, you can protect revision marks, comments, and sections of a document containing forms. A password can be added if desired. To display the Protect Document dialog, click Tools in any of the Office 2011 applications and choose Protect Document from the menu.