LogIn shells
From Linuxintro
(Redirected from Login shells)
A login shell is a shell to which you log in via console or ssh. This is also true if you have not given your username and password due to passwordless login. If you change your user with the su or sux command, this is no login shell. If you log in using the display manager and start a shell, this is no log in shell. If you call bash -login, you are in a login shell (bash), although you did not login at all.
When you start a login shell, login-scripts will be started, and if you start a shell that is not a login shell, other scripts will be started.
What is a login shell
| action | log-in-shell |
|---|---|
| you enter a computer with ssh, typing username and password | yes |
| you enter a computer with ssh using passwordless login | yes |
| you enter a computer by logging in to the Window Manager, using username and password. Then you open konsole by clicking on it. | no |
| you open a console and type su -, then password | yes |
| you open a console and type bash - | yes |
Example
Here is an example showing which login process calls what scripts:
tweedleburg:~ # su - tstaerk This is /etc/profile.d/run-on-login-for-all-sh-users.sh This is /etc/bash.bashrc This is .bashrc this is .bash_profile tstaerk@tweedleburg:~> exit logout tweedleburg:~ # su tstaerk This is /etc/bash.bashrc This is .bashrc tstaerk@tweedleburg:/mnt/barracuda/root> exit exit tweedleburg:~ # ssh tstaerk@localhost Warning: untrusted X11 forwarding setup failed: xauth key data not generated Warning: No xauth data; using fake authentication data for X11 forwarding. Last login: Sun Jan 12 09:42:47 2014 from localhost Have a lot of fun... This is /etc/profile.d/run-on-login-for-all-sh-users.sh This is /etc/bash.bashrc This is .bashrc this is .bash_profile tstaerk@tweedleburg:~> cat /etc/motd Have a lot of fun... tstaerk@tweedleburg:~> exit
Files
The scripts that you can change to control the behavior when logging in are as follows:
- /etc/profile.d/*.sh
- These scripts will be executed on login to sh shell for all users
- /etc/profile.d/*.bash
- These scripts will be executed on login to bash shell for all users
- /etc/profile.d/*.tcsh
- These scripts will be executed on login to tcsh shell for all users
- /etc/profile.d/*.csh
- These scripts will be executed on login to csh shell for all users
- /etc/bash.bashrc
- This script will be executed for all users that start bash shell
- ~/.bash_profile
- This script is specific for the user. It is situated in their home directory. The script is executed on login to bash.
- ~/.bashrc
- This script is specific for the user. It is situated in their home directory. The script is executed on start of bash.
- ~/.alias
- sourced by .bashrc if it exists
- /etc/motd
- displayed for login shells by the login process as a greeting
