What is the difference between Login and Non-Login Shell

If the output is the name of our shell, prepended by a dash, then it is a login shell. For example -bash, -su etc. A Non login shell is started by a program without a login. In this case, the program just passes the name of the shell executable.

1. What's a login shell?
2. How do you tell if a shell is a login shell?
3. How do I open a non login shell?
4. What is the difference between an interactive shell and a non-interactive shell?
5. Is Shell a login?
6. What is no login shell?
7. How do I know my login shell?
8. How do I know if I have zsh or bash?
9. Which command is used to identify files?
10. What is Run command as a login shell?
11. What is Shell bash login?
12. Should I use Bashrc or Bash_profile?

What's a login shell?

A login shell is a shell given to a user upon login into their user account. This is initiated by using the -l or --login option, or placing a dash as the initial character of the command name, for example invoking bash as -bash.

How do you tell if a shell is a login shell?

To check if you are in a login shell:

There's no portable and fully reliable way to test for a login shell. Ksh and zsh add l to $- . Bash sets the login_shell option, which you can query with shopt -q login_shell .

How do I open a non login shell?

Another way to get a non-interactive login shell is to log in remotely with a command passed through standard input which is not a terminal, e.g. ssh example.com <my-script-which-is-stored-locally (as opposed to ssh example.com my-script-which-is-on-the-remote-machine , which runs a non-interactive, non-login shell).

What is the difference between an interactive shell and a non-interactive shell?

Interactive: As the term implies: Interactive means that the commands are run with user-interaction from keyboard. E.g. the shell can prompt the user to enter input. Non-interactive: the shell is probably run from an automated process so it can't assume it can request input or that someone will see the output.

Is Shell a login?

Login shell is the first process that executes under our user ID when we log in to a session. The login process tells the shell to behave as a login shell with a convention: passing argument 0, which is normally the name of the shell executable, with a “ - ” character prepended.

What is no login shell?

nologin displays a message that an account is not available and exits non-zero. It is intended as a replacement shell field to deny login access to an account. If the file /etc/nologin. txtexists, nologin displays its contents to the user instead of the default message.

How do I know my login shell?

cat /etc/shells – List pathnames of valid login shells currently installed. grep "^$USER" /etc/passwd – Print the default shell name. The default shell runs when you open a terminal window. chsh -s /bin/ksh – Change the shell used from /bin/bash (default) to /bin/ksh for your account.

How do I know if I have zsh or bash?

Update your Terminal preferences to open the shell with the command /bin/bash , as shown in the screenshot above. Quit and restart Terminal. You should see "hello from bash", but if you run echo $SHELL , you will see /bin/zsh .

Which command is used to identify files?

The file command uses the /etc/magic file to identify files that have a magic number; that is, any file containing a numeric or string constant that indicates the type. This displays the file type of myfile (such as directory, data, ASCII text, C program source, or archive).

What is Run command as a login shell?

1 Answer

1. When running as a login shell, Bash will read ~/. bash_profile (or, if that doesn't exist, ~/. profile ) on startup. In some cases, this file reads ~/. bashrc as well.
2. When running as a non-login shell, Bash will read ~/. bashrc .

What is Shell bash login?

When bash is invoked as an interactive login shell, or as a non-interactive shell with the --login option, it first reads and executes commands from the file /etc/profile, if that file exists. After reading that file, it looks for ~/. bash_profile, ~/.

Should I use Bashrc or Bash_profile?

bashrc is sourced on every start in interactive mode when bash(1) does not act as a login shell. . bash_profile is only sourced when bash(1) is started as an interactive login shell, or as a non-interactive shell with the --login option. ... bash_profile is great for commands that should run only once and .