UNCA CSCI 107 -- Unix File Permissions

VERY MUCH UNDER CONSTRUCTION
However, this command just lists the names of your files and directories. If you want a more information listing, try the ls command with the -l option.

The output of this command will be lines looking like the following:

In this particular case, information is being given about the directory public_html and the file ur-city.gif. The first letter of the line is (almost always) a d, for directory, or -, for file.

The next nine characters give the permissions associated with the file. The nine characters are three groups of three characters. Let's look at the public_html file as an example. The three groups are rwx, r-x, and r-x. The meaning of these letters are given in the following table:

r
Read permission
w
Write permission
x
eXecute permission

Execute permission is a little difficult to understand. For files, it really it associated with the capability to execute the file as a program. However, for directories, it is associated with the capabilities to access files and sub-directories of the directory.


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