Invisible files

Posted on December 1st, 2006 by richard



Files that begin with a dot . are invisible to Mac OS X. They’re also not typically shown in Unix, but it’s easy to change that. For example, if you open Terminal and type ls you’ll see Desktop, Documents, etc. But if you type ls -a you’ll also see additional hidden files that begin with a dot.

The dot is useful for hiding configuration files that might otherwise clutter your view. On a web server like Apache, files beginning with a dot can’t be accessed over the web. That’s why you can safely put configuration options for each directory in an .htaccess file. (If you have a web site, you’ve almost certainly seen .htaccess files.)

In addition to the Unix method of hiding files by beginning them with a dot, Mac OS X also includes its own unique way of hiding files and folders. If you install the Developer Tools CD that came with your Mac, you’ll have access to a SetFile command. You can type SetFile -aV and the name of a file to make the file invisible. You can use SetFile -av (lowercase “v”) to make the file visible again.

In addition, you can see ALL the files on a computer by using Applications like Smultron that have an “Open Hidden” option.

Posted in Lessons, Unix |

One Response to “Invisible files”

  1. Glenn Kerbein Says:
    December 1st, 2006 at 9:45 am

    You can also use the ls -A to list all files, including those with a “.” beginning. The -A flag does not list “.” or “..”, which are relative directories, the current directory and one directory up, respectively.
    Most httpds, including apache, do respect “dot files”, except .htaccess files, since they contain configuration directives that should not be seen by anyone/thing other than the web server.

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