One important Unix command tells you everything you ever wanted to know about Unix commands and files: the man command. It displays information about commands and files documented in the on-line manual pages. These
man pages are included with every version of Unix.
The man pages present information about a command one page at a time. You can use keystrokes to advance to the next line or page of the man pages. You must quit the man pages feature to enter other Unix commands.
Like a book, man pages are broken into chapters called
sections (Table 1 ). Each section is designed for a specific type of user. For example, a programmer will be interested in different man pages than a user or a system administrator. There are some man pages that document identical sounding items yet are intended for different users.
Section | Type of Command or File |
|---|---|
1 | User commands |
2 | System calls |
3 | Library routines |
4 | I/O and special files |
5 | Administrative files |
6 | Games |
7 | Miscellaneous |
8 | Administrative and maintenanc commands |
The man pages for commands and files can be lengthy and complex. Don't worry if you don't understand everything on a man page. Just take what you need. As you understand more about Unix, more will make sense.
Type man followed by the name of the command (for example, man ls), and press
The first page of the reference manual for the command appears (Figure 8 ).
ls command.
Press
The manual advances one line.
Press
The manual advances one page (Figure 9 ).
ls command.
Press
Terminal returns you to the shell prompt.
Type man man and press
The first page of the reference manual for the online manual appears (Figure 10 ).
man .