What are permissions?

Every Unix file has a set of permissions associated with it that specify who is allowed to use that file and in what way.

There are three kinds of permissions:

1. A read permission means someone can see what is in the file.
2. A write permission means someone can change what is in the file, or even remove it.
3. An execute permission means someone can run (execute) a file, if that file contains a program.

• The owner permissions specify what the owner of the file can do.
• For a discussion of group permissions, see `Limiting file access to specific people'.
• The world permissions specify what anyone can do.

John Shipman, john@nmt.edu Last updated: 1995/12/04 19:39:34 UT URL: http://www.nmt.edu/tcc/help/unix/whatperm.html