Linux also has a tcsh shell (a C shell look-alike) and an ash shell
(another Bourne shell look-alike). Several different shells are introduced in
this chapter.
The odds are strong that the Linux distribution you are using has
more than one shell installed by default and available for your use.
Several major reasons for learning how to use the shell are:
You will know how to get around any Linux or other UNIX-like
system. For example, I can log in to my Red Hat Enterprise Linux
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IN THIS CHAPTER
Understanding the Linux shell
Using the Linux shell
Working with the Linux file
system
Using the vi text editor in Linux
Running Commands
from the Shell
MySQL server, my bootable floppy router/firewall, or my wife??™s iMac and explore and use
any of those computer systems from a shell.
Special shell features enable you to gather data input and direct data output between
commands and the Linux file system. To save on typing, you can find, edit, and repeat
commands from your shell history. Many power users hardly touch a graphical interface,
doing most of their work from a shell.
You can gather commands into a file using programming constructs such as conditional
checks, loops, and case statements to quickly do complex operations that would be
difficult to retype over and over.
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