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chicha

Member

From: France

Registered: 2007-04-20

Posts: 271

How to identify if I am using a login shell or not ?

Hello all,

I can identify if I am in an interactive shell by checking for an occurance of 'i' in the variable '$-'.
I already know how to invoke an interactive login shell (bash --login for instance).
Let's say that I use a shell and I do not know how it was invoked ...
The question is how can I identify if I am in a login shell ?

Thank you for your help
Cheers,
Chicha

.:B:.

Forum Fellow

Registered: 2006-11-26

Posts: 5,819

Website

Re: How to identify if I am using a login shell or not ?

Quite easy... Any login shell will ask you for a username and password. Otherwise, it wouldn't be a login shell...

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chicha

Member

From: France

Registered: 2007-04-20

Posts: 271

Re: How to identify if I am using a login shell or not ?

Thank you B for your help
But the exact question is :

Let's say that I use a shell and I do not know how it was invoked ...

Anyway I found a workaround :

echo $0

This will display 'bash' (or zsh, csh ...) in an interactive non-login shell and '-bash' (or -zsh ...) in an interactive login shell (notice the minus in front of the shell name).

I do not know if there is another way to find this information...
Cheers
Chicha

Borosai

Member

From: Sandy Appendix, U.S.A.

Registered: 2006-06-15

Posts: 227

Re: How to identify if I am using a login shell or not ?

This is taken from the zsh user guide. I guess it's not the most practical solution, but it works.

if [[ -o login ]]; then
    print yes
  else
    print no
  fi

chicha

Member

From: France

Registered: 2007-04-20

Posts: 271

Re: How to identify if I am using a login shell or not ?

Thank you Borosai
This work very well for zsh and is exactly what I am looking for.
Any idea about how to do this with bash (the login option does not exist) ?

Borosai

Member

From: Sandy Appendix, U.S.A.

Registered: 2006-06-15

Posts: 227

Re: How to identify if I am using a login shell or not ?

I have no idea about bash...sorry.

chicha

Member

From: France

Registered: 2007-04-20

Posts: 271

Re: How to identify if I am using a login shell or not ?

No problem
You gave me a good trick anyway !
Cheers,
Charles-Henri