home unix

Add a menu for a user's login

http://www.kingcomputerservices.com/unix_101/shell_programming_and_simple_menus_part_1.htm

create the menu

add a menu to the login shell:

http://forums11.itrc.hp.com/service/forums/questionanswer.do?admit=109447626+1272916334344+28353475&threadId=1265970

/etc/shell entry >> Only if you want FTP to work.

user1:*:1000:200::/home/user1:/usr/local/bin/menu.ksh

 

One very important feature that your menu script (as well as every* shell script) must have is line #1 with the interpreter listed. If you write the script in ksh, then line 1 must be:

#!/usr/bin/ksh

Or if you use the POSIX shell: #!/usr/bin/sh

And of course the script must be executable by all the users, typically 755 (never 777) permissions.

What will happen at login is that the menu script will be run and any attempt to exit the script returns to another login request. Make sure your script does not provide a menu item for vi or other program that allows the user to call a shell (using the ! character). Just to be sure, you can set the SHELL variable in your script:

export SHELL=/usr/bin/false

Change shell using chsh

http://www.debian-administration.org/articles/231

chsh stands for change shell, and does exactly what the name suggests.

Invoke it with no arguments and you will be prompted for your password, then you will be prompted for your shell.

The file /etc/shells is consulted, and your chosen shell must be included in there for your change to be accepted. If you enter the name of a binary which is not contained in /etc/shells you'll receive and error similar to this:

skx@mystery:~$ chsh Password: Changing the login shell for skx Enter the new value, or press return for the default Login Shell [/bin/sh]: /bin/fff /bin/fff is an invalid shell.

 

If you're root you can change the shell for a user by adding the username to the command line:
root@mystery:~# chsh skx

 

You can also supply the shell name without being prompted for it interactively with the -s argument:
root@mystery:~# chsh skx

 

You can also supply the shell name without being prompted for it interactively with the -s argument: 
root@mystery:~# chsh -s /bin/zsh skx

Or:

skx@mystery:~$ chsh  -s /bin/bash   
Password:

[root@earth etc]# chsh -s /usr/local/bin/lmumenu.ksh lmu
Changing shell for lmu.
Warning: "/usr/local/bin/lmumenu.ksh" is not listed in /etc/shells
Shell changed.

Captive Logins with ssh

http://ubuntuforums.org/archive/index.php/t-385239.html