Re: interactive shell detection in shrc

On Mon, Sep 30, 2024 at 12:14:44PM -0700, Greg A. Woods wrote:
> > SHELL is set by ksh and not by sh (sh handles NETBSD_SHELL), if I'm
> > not mistaken?
> 
> login(1) sets $SHELL, and in the BSD world it has done so since 4.2 or
> before.  In the AT&T Unix world it has done so since at least 
> System III, aka UNIX 3.0.
> 

What I mean is that if I'm under ksh, and then I switch to sh even
explicitely setting interactive :

$ printenv

_=/usr/bin/printenv
...
SHELL=/bin/ksh
...

$ sh -i
$ printenv

...
SHELL=/bin/ksh
...

and the same result with "sh -l" (supposed to be considered a login
shell).

So how can the test be reliable in all circumstances?

-- 
        Thierry Laronde <tlaronde +AT+ kergis +dot+ com>
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