What's a shell?
Your shell is the program that gives you a command prompt, waits for
you to type commands and does what you type. By default, when you log
in to our unix systems, you are using a shell named ksh. Ksh is a
fine shell and you can learn more about it by reading its man page.
If you would like to try some other shell programs, you may find one
that is more to your liking than the default. Our systems support a
number of different shell programs. You can get a list of the
supported shells by typing:
cat /etc/shells
Different people like different kinds of shell programs. Depending on
the shell you choose, you can get it to do some nice things for you
like:
- Remember commands that you typed before
- Automatically complete filenames based on what you have already typed.
- Let you edit commands you type rather than type them over.
- Manage background and foreground tasks.
- Write big, fancy commands in a built-in scripting language.
You can try out these alternate shells by simply running them from
your regular shell program. For example, you can just run bash or
tcsh to see how they work. More information about these shells is
available from their man
pages.
Changing your default shell
When you want to change the shell that you get when you log in, there
is a program to do that for you. Just type:
chsh
This program will ask you for the shell that you want to use. You can
pick any shell that's listed in the /etc/shells file.