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Invisible Files: Working with Invisible Files

Here are three examples of situations in which the ability to work with invisible files was required for solving a problem.

Saving movie trailers that have the Save option disabled

When you're viewing QuickTime movies on the Web, such as movie trailers, you usually can choose to save the movie to your hard drive (although you need to have upgraded to QuickTime Pro). Still, the Web site can choose to have this option disabled, even for QuickTime Pro users. Nonetheless, you usually can save the file. Assuming that you are using Internet Explorer, follow these steps:

  1. Enable the Save Movies in Disk Cache option in the Plug-In tab of the QuickTime System Preferences window.

  2. Immediately after viewing the movie, go to

    <~/Library/Preferences/Explorer/Temporary Items/>.

    The QuickTime movie file may be stored there (although it will likely have a different name than the name of the movie itself).

  3. If you find the file, drag it out of that folder. You are done.

If the preceding method does not work, access to invisible files comes into play. Follow these steps:

  1. Enable TinkerTool's Show Hidden and System Files option.

  2. Choose Go to Folder from the Finder's Go menu, and enter /tmp/ in the text box of the window that appears.

    The tmp folder window should now open in the Finder. You should find a folder in the window with a number as its name (probably, 501). This number is the same as the User ID number for the logged-in user.


    In case you were curious, you can identify your user ID number by launching NetInfo Manager, choosing Users, and then selecting your user name. At the bottom of the window, search for the property that says <uid>. The number in the adjacent Value column is your user ID. Alternatively, when you're in Terminal, type <id>.

  3. Open the 501 (or whatever number it is) folder.

    Inside, there should be a file with a name that starts with QuickTimePlugIn.

  4. Drag the file to the Desktop.

  5. Turn off TinkerTool's Show Hidden and System Files option.

  6. Use a utility such as FileXaminer or XRay to change the type and creator of the file from whatever they are to MooV and TVOD, respectively.

  7. Open the Show Info window for the file, and make QuickTime Player the Open with Application selection.

    This change should also change the file's icon.

  8. Rename the file however you want.

  9. Double-click the file, and enjoy.

Saving package files downloaded from Software Update. I use essentially the same method to save files downloaded from Software Update.


"Use a stand-alone installer/updater," in Chapter 2.

Saving the Stickies database file

The Stickies application included with Mac OS X allows you to save notes in colored windows that resemble Post-it notes. Unfortunately, due to an apparent bug in Mac OS X, the data file that contains all your saved notes may get deleted after certain actions. I have seen this situation happen after some users installed the Mac OS X 10.1.2 upgrade . The result is that Stickies reverts to the default notes that appear the first time you launch it; your saved notes are lost.

Although you may not be able to prevent this file from being deleted, you can protect yourself against the loss of the data by maintaining a backup of the Stickies data file. Doing so, however, is complicated because the data file is invisible. The following paragraphs explain how to solve this problem.

Use TinkerTool. Follow these steps:

  1. Enable TinkerTool's Show Hidden and System Files option.

  2. Go to ~/Library (such as the Library folder in your Home directory).

  3. Locate a file called .StickiesDatabase, make a copy of this file, and drag the copy to another location.

  4. Eliminate the period at the start of the file name.

    This step allows the file to remain visible even after you reverse the TinkerTool option.

  5. Turn off the TinkerTool option so that invisible files are invisible again. Now you have a backup of your Stickies database file. Back up the file again as often as needed, especially before performing an action (such as an OS upgrade) that is known to be a potential cause of the file deletion.

If your Stickies file gets deleted, reverse the preceding procedure and follow these steps:

  1. Use TinkerTool to make invisible files visible.

  2. Make a copy of your backup database, and give it the same name as the original except for the dot added as the first character.

  3. Drag the file to the ~Library folder (replacing the file that is already there, if necessary).

  4. Undo the TinkerTool change so that invisible files are invisible again.

    Your Stickies notes should be restored.

Use Terminal. You can also use Terminal to back up and restore the Stickies database.

To back up the database file, launch Terminal, and type <cp Library/ .StickiesDatabase Documents/StickiesDatabase>.

To restore the database file, launch Terminal, and type <cp Documents/ StickiesDatabase Library/.StickiesDatabase>.

To facilitate using these commands, save a copy of each command line as a text clipping. Then simply drag the text clipping to the Terminal window to paste it in. Press Return, if necessary, and the command will execute. (Note: In Chapter 10, I describe an alternative to text clippings for commands such as these: shell scripts.)

These commands create a file called StickiesDatabase in your Documents folder. You can select a different destination, if you want.

Modifying Unix files

Mac OS X keeps its essential Unix directories invisible in the Finder. These directories include bin, etc, sbin, tmp, var, usr, and Volumes. In both Chapter 4 ("Take Note: What and Where are the Unix Files") and Chapter 10, I provide more detail about what is in these directories and how to use Terminal to access their contents. For now, I want to focus on how and why to edit some of these Unix files from the Finder.


In Unix (as accessed from Terminal), only files that begin with a dot are considered to be invisible. Other files are listed as visible, even if they are invisible in the Finder.

Unix uses several configuration files to determine the settings and preferences of a variety of features (such as network settings). Actually, in some cases, when you change a System Preferences setting in the Finder, you are modifying the contents of one of these Unix files. These files are mostly stored as text files in Unix's etc directory. Occasionally, you may want to change a setting in one of these files that cannot be changed via System Preferences or any other Mac OS X feature. The solution is to edit the configuration file directly.

Assuming you are familiar with Unix, you can always use Terminal to access and edit these files, such as by typing <sudo pico {path of file}> to open a file in Unix's pico text editor via root access. I prefer to work in Aqua whenever possible, however. Fortunately, BBEdit Lite makes this especially easy to do. You do not even have to make the invisible folders or files visible in the Finder. Follow these steps:

  1. Launch the shareware utility Pseudo (needed to open BBEdit with root access).

  2. Drag the BBEdit Lite icon to the Pseudo window, and enter your password when you are requested to do so.

  3. Now BBEdit Lite is open with root access.

  4. Choose Open Hidden from BBEdit's File menu.

  5. Navigate to the desired folder, and open the desired file.

  6. Edit and save the file.

BBEdit includes a feature that allows owners of a read-only file to change the file's permissions so that it is writable. You cannot use this feature to modify a file owned by root, however. That is why you need to follow the above steps instead.


You used to be able to type <sudo open {path of application}> in Terminal to mimic the effect of the Pseudo utility. But starting with an update to Mac OS X 10.1, Apple disabled this feature.


See "Take Note: Opening .app Files from Within Terminal," earlier in this chapter, for an exception to this exception.

Unix files that may need editing. Following are three examples of Unix files you might need to modify at some point.

Inetd.conf. Mac OS X uses TelnetSSH for making Telnet connections over a network. The SSH protocol provides greater security than the older plain Telnet. If you want or need to use the older, less secure Telnet, you will need to change the /etc/inetd.conf file. To do so, open the file in BBEdit and then follow these steps:

  1. Locate the lines that read #telnet; #shell; and #login.

  2. Remove the # character from the start of each line.

  3. Save the file.

  4. Restart the Mac.


"Technically Speaking: Secure Connections," in Chapter 8, for more on SSH.

Hostconfig. If, when you're trying to mount a removable medium (such as a CD), you get an error message that states, "You have inserted a disk containing volumes that Mac OS X can't read," you may need to modify the /etc/hostconfig file. See Apple Knowledge Base article #106345 <> for complete details.

Httpd.conf. If Web Sharing refuses to start up, you may need to modify the /etc/httpd/httpd.conf file. See Apple Knowledge Base article #106505 <> for complete details.


Note: Updates to Mac OS X eventually fix identified problems, such as the latter two described in this section, so that these file changes are no longer needed. Still, new reasons to edit these files keep cropping up.


"Technically Speaking: The Root User Desktop," in Chapter 9.

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