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1. Get a Linux account

All registered students and U of M staff should already have a working U of M userid and password. This is all you need to use the CCL Linux system.

2. Setting up a default shell

Since you'll be typing several commands, you need a terminal window. From the Applications menu, choose Applications --> System tools --> Terminal.
A terminal window should pop up:

The shell is a program that executes commands. Every time you type a command, or every time a program is run from your account, the shell runs that command. There is a choice of shells on most Unix systems, including the Bourne shell (sh), the Bourne-Again shell (bash), the C-shell (csh) the K-shell (ksh) and the T-shell(tcsh).  BIRCH can run using  any shell as the default shell. Unless you have a favorite shell, we recommend bash for most users. In particular, avoid the Bourne shell (/bin/sh) because it can't display the current working directory in the command prompt. To  find out your default shell, type

echo $SHELL

If the command returns


then you are using bash and don't need to change it.

UPDATE September 9, 2017: All new Linux accounts should now default to the bash shell. If you have an older account, your default shell might be something other than bash, such as /bin/ksh. In that case, you need to get your default shell changed to bash by IST. Either send an email request to, or go to one of the IST offices listed on the Central Computing Unix System page.

3. Set permissions to ensure security
For better security, the following steps are recommended to set permissions, which govern who may or may not have access to files in hour $HOME directory. In general, all of your files and directories should be accessible only to you, unless there is a specific reason for making them available to others. At the command prompt, type each command in the left column below, in the order shown.


chmod go-rw $HOME

chmod go-rwx *

go to your $HOME directory

turn off (-) permissions for others (go) to read or write (rw) your $HOME directory

turn off permissions for others to read, write or search files or directories within your $HOME directory

4. newuser - set the path and environment variables

Now you're ready to run the newuser script.

Two things need to be setup in order to use the programs. First, your $PATH must include the directories in which BIRCH executable files are found. Secondly, many of the programs need to know where to find data or configuration files. The locations of these files are specified by environment variables that are automatically set when you login.

All of these processes can be made transparent to the user by running the 'newuser' command. At the command prompt, type


This will add some lines to your .login and .cshrc  and .profile files, which contain commands that execute each time you login. (Comparable to AUTOEXEC.BAT in DOS). These commands 1) set your path 2) set your environment variables, 3) set your prompt to display the current working directory and hostname.

Now, open a new terminal window. It should now look something like this.

The login host name and the path to your home directory will appear inside curly brackets {}.

5. The GNOME window manager

A window manager is a program that executes when you login from a terminal or workstation. It controls how windows are displayed, what windows can do, and the types of programs that can be launched by pointing and clicking. Most desktop programs can be run regardless of the window manager in use.

The default window manager on this platform is the GNOME Desktop.

Next: Customizing your desktop

What if I want to remove BIRCH access from my user account?

To remove BIRCH access for your account, type


This deletes the lines that were added by the 'newuser' script to your .login, .cshrc, .profile, .bash_profile, and .bash_login  files. (All of these lines contain the string '#_BIRCH'). You can always restore BIRCH access by running 'newuser' as described above.