3.1 File Concepts

The file is the basic unit in the SunOS operating system. Almost everything is treated as a file, including:

• Documents--These include text files, such as letters or reports, computer source code, or anything else that you write and want to save.

• Commands--Most commands are executable files; that is, they are files you can execute to run a particular program. For example, the date command that you saw in the previous chapter, which executes a program that provides the current date, is an executable file.

• Devices--Your terminal, printer, and disk drive(s) are all treated as files.

• Directories--A directory is simply a file that contains other files.

The following section explains the commands available for creating, listing, copying, moving, and deleting files. You'll also see how to list the contents of a file and how to determine the nature of a file.