logout from interactive subshell

logout from interactive subshell

[Com MN PG P E B Consultant 3]

Does someone know how to deal with the following situation?

Very often I do the following pattern:

   (1) rlogin to a foreign host
   (2) Invoke a subshell (for example because I'm setting a Clearcase
View)
   (3) Logout from the host

Step (3) needs two steps: First I have to type 'exit' to leave the
subshell,
and then either 'exit' or 'logout' to leave the login shell.

Is it possible to automate this in such a way that I have to type only
one
command, to leave all subshells (in this case, only 1, but in general, I
might be several subshells deep) AND then logout?

One idea would be to use ps, locate the process to the current subshell,
crawling upwards via the PPIDs to find the PID of the login shell, and
kill
it. But this seems to be such an awkward solution, that I thought maybe
there is an easier way to do it.

(Note: This posting goes to the bash and to the zsh mailing list,
because this problem
might be solved differently in both shells, and I'm interested in both
solutions - of
course a solution working in bash AND zsh would be preferable).

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

Re: logout from interactive subshell

[Mikael Magnusson]

On 10/12/06, Com MN PG P E B Consultant 3
<mn-pg-p-e-b-consultant-3.com@siemens.com> wrote:
> Does someone know how to deal with the following situation?
>
> Very often I do the following pattern:
>
>    (1) rlogin to a foreign host
>    (2) Invoke a subshell (for example because I'm setting a Clearcase
> View)
>    (3) Logout from the host
>
> Step (3) needs two steps: First I have to type 'exit' to leave the
> subshell,
> and then either 'exit' or 'logout' to leave the login shell.
>
> Is it possible to automate this in such a way that I have to type only
> one
> command, to leave all subshells (in this case, only 1, but in general, I
> might be several subshells deep) AND then logout?
>
> One idea would be to use ps, locate the process to the current subshell,
> crawling upwards via the PPIDs to find the PID of the login shell, and
> kill
> it. But this seems to be such an awkward solution, that I thought maybe
> there is an easier way to do it.

How about
function rlogin() {command rlogin "$@"; exit}
?

-- 
Mikael Magnusson

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> How about
> function rlogin() {command rlogin "$@"; exit}
> ?

Hmmmm.... I don't see how this could help me. Actually, your
solution would EXIT the shell I came from, after the login
has finished!! So I not only have to type all the "exit"s on
the remote host, I would even loose my current shell on the
local host.

Maybe to repeat what I would like to do:

A typical application would go like this:

   rlogin foobar
   DO SOME STUFF
   cleartool setview myview # this creates a subshell
   DO MORE STUFF
   cleartool setview yourview # now I'm two subshells deep
   DO STILL MORE STUFF
   # Now I want to exit
   exit
   exit
   logout

I would like to have a (interactive) command which does the final two
exits plus
a logout for me.

BTW, I could imagine a solution using 'expect', which does the login,
then hands
over the control to the user, and finally if the user is done, performs
the
exit and logout.

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

 

Re: logout from interactive subshell

[Peter Stephenson]

"Com MN PG P E B Consultant 3" wrote:
>    rlogin foobar
>    DO SOME STUFF
>    cleartool setview myview # this creates a subshell
>    DO MORE STUFF
>    cleartool setview yourview # now I'm two subshells deep
>    DO STILL MORE STUFF
>    # Now I want to exit
>    exit
>    exit
>    logout

You can turn cleartool into a function that exits the shell after
running the real cleartool.

cleartool() { command cleartool "$@"; exit; }

Works in both shells.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070


To access the latest news from CSR copy this link into a web browser:  http://www.csr.com/email_sig.php

Re: logout from interactive subshell

[Lloyd Zusman]

"Com MN PG P E B Consultant 3"
<mn-pg-p-e-b-consultant-3.com@siemens.com> writes:

>> How about
>> function rlogin() {command rlogin "$@"; exit}
>> ?
>
> Hmmmm.... I don't see how this could help me. Actually, your
> solution would EXIT the shell I came from, after the login
> has finished!! So I not only have to type all the "exit"s on
> the remote host, I would even loose my current shell on the
> local host.
>
> Maybe to repeat what I would like to do:
>
> A typical application would go like this:
>
>    rlogin foobar
>    DO SOME STUFF
>    cleartool setview myview # this creates a subshell
>    DO MORE STUFF
>    cleartool setview yourview # now I'm two subshells deep
>    DO STILL MORE STUFF
>    # Now I want to exit
>    exit
>    exit
>    logout
>
> I would like to have a (interactive) command which does the final two
> exits plus
> a logout for me.
>
> BTW, I could imagine a solution using 'expect', which does the login,
> then hands
> over the control to the user, and finally if the user is done, performs
> the
> exit and logout.

With clearcase in the picture, this becomes complicated, due to the fact
that cleartool automatically puts you into a subshell whether you like
it or not.  That's one of several reasons for why I don't like
clearcase.

But given that you're probably stuck having to use it, you might try
something like this (assuming that you're using zsh):

Put this into your ~/.zlogin:

  [[ ${SHLVL:-0} == 1 ]] && {
    export LOGINPID=$$
  }

Then, after your "# Now I want to exit" comment (above), do this:

  kill -9 $LOGINPID

You can make this into an alias, if you wish.

It's an ugly hack, but it may be the only thing that you can do, given
that you're using clearcase.

I think it will work, but I can't test it, because clearcase isn't
installed on any of my machines.

Good luck!


-- 
 Lloyd Zusman
 ljz@asfast.com
 God bless you.

Re: logout from interactive subshell

[Bart Schaefer]

On Oct 12,  6:07am, Lloyd Zusman wrote:
}
} "Com MN PG P E B Consultant 3"
} <mn-pg-p-e-b-consultant-3.com@siemens.com> writes:
} 
} >    # Now I want to exit
} >    exit
} >    exit
} >    logout
} 
} Put this into your ~/.zlogin:
} 
}   [[ ${SHLVL:-0} == 1 ]] && {
}     export LOGINPID=$$
}   }
} 
} Then, after your "# Now I want to exit" comment (above), do this:
} 
}   kill -9 $LOGINPID

Yowtch.  This is the right idea, but "kill -9" is way overboard; that
kills the process instantly without letting it do any cleanup (like
saving history), and effectively orphans the sub-shells, which you are
then counting on to exit on their own.

Much better would be to use "kill -HUP" which tells the shell process
its terminal connection has been closed (even though it hasn't, really).
Zsh will then send HUP signals to all its children [*] and exit mostly
in the same manner as if you'd typed "logout".

[*] Unless you have "setopt no_hup" in which case you'll need to do
this a slightly different way.

So here's a variation of Lloyd's suggestion:

----
# This goes in ~/.zprofile for login shells only:
export LOGINPID=$$

# This goes in ~/.zshrc for all interactive shells:
if [[ ${LOGINPID:-$$} != $$ ]]
then function logout { kill -HUP $LOGINPID; exit }
fi
----

Now if you want to stop all the shells, you type "logout", and otherwise
you type "exit".

If you have "setopt no_hup" and only want to kill shells, leaving other
processes running in the background, modify the ~/.zshrc part:

----
# This goes in ~/.zshrc for all interactive shells:
trap logout USR1

if [[ ${LOGINPID:-$$} != $$ ]]
then
  function logout { kill -USR1 $PPID; exit }
fi
----

That should cause a chain of USR1 signals to climb up to the ultimate
login shell, with each shell exiting after passing along the signal.
You can pick another trappable signal if USR1 is not appropriate.

Re: logout from interactive subshell

[Vincent Lefevre]

On 2006-10-12 07:58:50 -0700, Bart Schaefer wrote:
> ----
> # This goes in ~/.zshrc for all interactive shells:
> trap logout USR1
> 
> if [[ ${LOGINPID:-$$} != $$ ]]
> then
>   function logout { kill -USR1 $PPID; exit }
> fi
> ----

You need to check that the parent process is an interactive zsh shell
since one can run a zsh login shell and a command in it that would
run an interactive zsh. I can see at least two cases where this can
happen:

1. With a text-mode login, then startx, then terminals with a zsh in
them.

2. With screen.

So, I suggest the following:

trap logout USR1
[[ $MYPID == $PPID ]] && logout() { kill -USR1 $PPID; exit }
export MYPID=$$

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/>
Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

Re: logout from interactive subshell

[Christian Taylor]

> A typical application would go like this:
>
>    rlogin foobar
>    DO SOME STUFF
>    cleartool setview myview # this creates a subshell
>    DO MORE STUFF
>    cleartool setview yourview # now I'm two subshells deep
>    DO STILL MORE STUFF
>    # Now I want to exit
>    exit
>    exit
>    logout
>
> I would like to have a (interactive) command which does the final two
> exits plus
> a logout for me.

I don't know how to do exactly what you have in mind, but I can think of two 
methods that may be of use to you. Both should (usually) work independent of 
which shell you use. The second is close to what you asked for.

1. Shortcut
You can hit "^D" instead of typing exit (or logout) to terminate the current 
shell. If you are three subshells deep, holding Ctrl and hitting "d" three 
times is quite a lot faster, but you still have to keep track of how many 
subshells you want to exit.

2. Screen
After you log into the remote box, start a screen session (simply 
type "screen"). Proceed to do your stuff. After you're done, hit "^A" 
followed by "k". Screen will ask you to confirm and then terminates all your 
subshells, as well as itself.
To logout automatically as well, I suggest you create an alias for the 
command "screen; logout" and run that after login.

(Screen is capable of much more, have a look at the man page if you're 
interested.)

hope this helps,
Christian

Re: logout from interactive subshell

[Brian K. White]

----- Original Message ----- 
From: "Christian Taylor" <cht@chello.at>
To: <zsh-users@sunsite.dk>
Sent: Thursday, October 12, 2006 6:16 AM
Subject: Re: logout from interactive subshell


>> A typical application would go like this:
>>
>>    rlogin foobar
>>    DO SOME STUFF
>>    cleartool setview myview # this creates a subshell
>>    DO MORE STUFF
>>    cleartool setview yourview # now I'm two subshells deep
>>    DO STILL MORE STUFF
>>    # Now I want to exit
>>    exit
>>    exit
>>    logout
>>
>> I would like to have a (interactive) command which does the final two
>> exits plus
>> a logout for me.
>
> I don't know how to do exactly what you have in mind, but I can think of 
> two
> methods that may be of use to you. Both should (usually) work independent 
> of
> which shell you use. The second is close to what you asked for.
>
> 1. Shortcut
> You can hit "^D" instead of typing exit (or logout) to terminate the 
> current
> shell. If you are three subshells deep, holding Ctrl and hitting "d" three
> times is quite a lot faster, but you still have to keep track of how many
> subshells you want to exit.
>
> 2. Screen
> After you log into the remote box, start a screen session (simply
> type "screen"). Proceed to do your stuff. After you're done, hit "^A"
> followed by "k". Screen will ask you to confirm and then terminates all 
> your
> subshells, as well as itself.
> To logout automatically as well, I suggest you create an alias for the
> command "screen; logout" and run that after login.
>
> (Screen is capable of much more, have a look at the man page if you're
> interested.)
>
> hope this helps,
> Christian

These answers come the closest to sanity in my opinion.
They don't exactly do what he wants but the fault lies in the request not in 
the shell or anyones knowledge of how to use it.

I'd have said there is no answer. Ultimately there is no way for any given 
process to know how far you mean when you say you want to log "all the way 
out" except it would/should be possible to say "all the way off this host" 
by talking to the daemon you logged in via. In fact that is possible but 
it's not garunteed to always work completely and there is one desireable 
level of control missing. (or, if what I'm about to describe is possible I 
hope to hear about it :)

rlogin, ssh, & telnet all support an escape character similar to classic cu.
Sometimes it's optional and not used by default, and it takes different 
forms between say telnet & ssh, but in some form, if desired, it's always 
available as an option.

In the case of ssh, On a new line (or hit enter blindly if you're terminal 
is messed up) type ~.
and you are disconnected from the ssh session.
sshd on the remote host then sends a HUP to all child processes of that 
session and in a perfect world they all react to this in a sane manner by 
cleaning up shop and exiting.

The problems are:
1) this isn't a perfect world and lots of apps don't die. you'll have to 
just try and see if you are stuck with any like that.
2) if you are connected from host to host to host, this breaks your closest 
connection, not your furthest one.
In a perfect world again, this does end up cleanly breaking all the 
subsequent connections and killing all the child processes on the the whole 
train of hosts all in one easy shot. Maybe thats what you wanted, in which 
case, fine, problem solved.

But if you only want to back out of your lest leg of the chain of 
connections and not destroy the whole chain, I don't know how to do that 
except by manually specifying a different escape character or sequence for 
each new connection, so the the escape code for one connection gets ignored 
and passed along as ordinary data by all the rest.

The I think it's outside the shells area of responsibility to even attempt 
to keep track of such things.

Brian K. White  --  brian@aljex.com  --  http://www.aljex.com/bkw/
+++++[>+++[>+++++>+++++++<<-]<-]>>+.>.+++++.+++++++.-.[>+<---]>++.
filePro  BBx    Linux  SCO  FreeBSD    #callahans  Satriani  Filk!

Re: logout from interactive subshell

[Phil Pennock]

On 2006-10-13 at 08:17 -0400, Brian K. White wrote:
> rlogin, ssh, & telnet all support an escape character similar to classic cu.

I believe that Mike Stroyan already offered this one -- probably a mail
delay somewhere holding up parts of the thread though.

> 2) if you are connected from host to host to host, this breaks your closest 
> connection, not your furthest one.

> But if you only want to back out of your lest leg of the chain of 
> connections and not destroy the whole chain, I don't know how to do that 
> except by manually specifying a different escape character or sequence for 
> each new connection, so the the escape code for one connection gets ignored 
> and passed along as ordinary data by all the rest.

Repeat the escape.

If the second character is the escape character, then it's sent on as
one character, so the second ssh process sees it.  So assuming that it's
not been changed with EscapeChar/-e, ~. for the first, ~~. for the
second, ~~~. for the third, etc.  For each ssh, all that matters is that
the ~ be the first _seen_ character typed after a newline.

More safely, ~? to see which escape sequences are offered, so that you
can check it's working without logging out, or ~^Z to suspend the login.
Knowing that one, for chained sessions, is a major productivity boost.

Regards,
-Phil

Re: logout from interactive subshell

[Brian K. White]

----- Original Message ----- 
From: "Phil Pennock" <phil.pennock@globnix.org>
To: "Brian K. White" <brian@aljex.com>
Cc: <zsh-users@sunsite.dk>
Sent: Friday, October 13, 2006 9:44 PM
Subject: Re: logout from interactive subshell


> On 2006-10-13 at 08:17 -0400, Brian K. White wrote:
>> rlogin, ssh, & telnet all support an escape character similar to classic 
>> cu.
>
> I believe that Mike Stroyan already offered this one -- probably a mail
> delay somewhere holding up parts of the thread though.

The delay was just in my inbox. I read his message a few minutes after 
sending mine.

>> 2) if you are connected from host to host to host, this breaks your 
>> closest
>> connection, not your furthest one.
>
>> But if you only want to back out of your lest leg of the chain of
>> connections and not destroy the whole chain, I don't know how to do that
>> except by manually specifying a different escape character or sequence 
>> for
>> each new connection, so the the escape code for one connection gets 
>> ignored
>> and passed along as ordinary data by all the rest.
>
> Repeat the escape.
>
> If the second character is the escape character, then it's sent on as
> one character, so the second ssh process sees it.  So assuming that it's
> not been changed with EscapeChar/-e, ~. for the first, ~~. for the
> second, ~~~. for the third, etc.  For each ssh, all that matters is that
> the ~ be the first _seen_ character typed after a newline.
>
> More safely, ~? to see which escape sequences are offered, so that you
> can check it's working without logging out, or ~^Z to suspend the login.
> Knowing that one, for chained sessions, is a major productivity boost.
>
> Regards,
> -Phil

Very nice, thanks.
Should have known that. cu probably does the same.

Brian K. White  --  brian@aljex.com  --  http://www.aljex.com/bkw/
+++++[>+++[>+++++>+++++++<<-]<-]>>+.>.+++++.+++++++.-.[>+<---]>++.
filePro  BBx    Linux  SCO  FreeBSD    #callahans  Satriani  Filk!

Re: logout from interactive subshell

[Vincent Lefevre]

On 2006-10-12 10:47:38 +0200, Com MN PG P E B Consultant 3 wrote:
> Does someone know how to deal with the following situation?
> 
> Very often I do the following pattern:
> 
>    (1) rlogin to a foreign host
>    (2) Invoke a subshell (for example because I'm setting a Clearcase
> View)

Is it a subshell or a second-level shell? (In the first case, $$ and
$PPID remain the same.)

>    (3) Logout from the host
> 
> Step (3) needs two steps: First I have to type 'exit' to leave the
> subshell, and then either 'exit' or 'logout' to leave the login
> shell.
> 
> Is it possible to automate this in such a way that I have to type
> only one command, to leave all subshells (in this case, only 1, but
> in general, I might be several subshells deep) AND then logout?
> 
> One idea would be to use ps, locate the process to the current
> subshell, crawling upwards via the PPIDs to find the PID of the
> login shell, and kill it. But this seems to be such an awkward
> solution, that I thought maybe there is an easier way to do it.

You don't need ps. Just get the ppid with $PPID if possible (see
above) or by some other mean (see thread "Subshells and parameters"
in the zsh-users archives). Each subshell can use a trap to be able
to kill its parent. But bash and zsh behave differently concerning
traps.

Alternatively, the command that invokes the subshell could call
'exit' after it has finished (you can write a wrapper, e.g. as a
shell function).

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/>
Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> >    (1) rlogin to a foreign host
> >    (2) Invoke a subshell (for example because I'm setting a 
> Clearcase
> > View)
> 
> Is it a subshell or a second-level shell? (In the first case, $$ and
> $PPID remain the same.)

Could you kindly explain the difference? I thought it's always the
same - a process (being the current shell, or cleartool, or whatever)
is doing a fork, followed by an exec of the new shell.

In the particular case of "cleartool setview", I don't know how it is
done, but here is an example of the PIDs:

$ echo $$
25494
$ echo $PPID
25493
$ cleartool setview rofi_dft
$ echo $$
2965
$ echo $PPID
25494

So PPID changed (which I thought is very natural, since I have a new
parent process now).

The same effect appears if I invoke "zsh" instead of "cleartool....", so
we have what
you call a "second-level shell".

Now I wonder what exactly would be a "subshell" then....

> Each subshell can use a trap to be able
> to kill its parent. But bash and zsh behave differently concerning
> traps.

I can't use traps here, because I know only at "exit time", whether
I want to logout completely, or just go up one level.

> Alternatively, the command that invokes the subshell could call
> 'exit' after it has finished (you can write a wrapper, e.g. as a
> shell function).

Here again, I would need to decide at the time I'm calling the
subshell, what to do at the exit-time.... so not useful for me
either.

Regards,

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

Re: logout from interactive subshell

[Bart Schaefer]

(I'm not sure why you copied bug-bash, but I've dropped it.)

On Oct 12, 12:20pm, Com MN PG P E B Consultant 3 wrote:
}
} > Is it a subshell or a second-level shell? (In the first case, $$ and
} > $PPID remain the same.)
} 
} Could you kindly explain the difference?

A subshell is a shell started with the "( ... )" construct or by
backgrounding a complex command such as a shell function or loop.
It's a shell that has been fork'd, but not exec'd.

A second-level shell is:

} a process (being the current shell, or cleartool, or whatever)
} is doing a fork, followed by an exec of the new shell.

The term "subshell" is often colloquially used to refer to both, but
they really aren't the same thing.

Re: logout from interactive subshell

[Matthew Woehlke]

Com MN PG P E B Consultant 3 wrote:
> Does someone know how to deal with the following situation?
> 
> Very often I do the following pattern:
> 
>    (1) rlogin to a foreign host
>    (2) Invoke a subshell (for example because I'm setting a Clearcase
> View)
>    (3) Logout from the host
> 
> Step (3) needs two steps: First I have to type 'exit' to leave the
> subshell,
> and then either 'exit' or 'logout' to leave the login shell.
> 
> Is it possible to automate this in such a way that I have to type only
> one command, to leave all subshells (in this case, only 1, but in
> general, I might be several subshells deep) AND then logout?

What about in your login (.bash_profile, etc) exporting a variable, say 
ROOT_PID=$$ and having a command/function/alias 'kill -s SIGHUP 
$ROOT_PID'? This is equivalent to killing the rlogin connection, but 
should clean up nicely if all you have are shells.

-- 
Matthew
"I don't question your existence -- God" (seen on a church billboard)

Re: logout from interactive subshell

[Mike Stroyan]

> Very often I do the following pattern:
>
>    (1) rlogin to a foreign host
>    (2) Invoke a subshell (for example because I'm setting a Clearcase
> View)
>    (3) Logout from the host
>
> Step (3) needs two steps: First I have to type 'exit' to leave the
> subshell,
> and then either 'exit' or 'logout' to leave the login shell.
>
> Is it possible to automate this in such a way that I have to type only
> one command, to leave all subshells (in this case, only 1, but in
> general, I might be several subshells deep) AND then logout?

  This shouldn't be a shell question at all.  It is an rlogin question.
Type ~. to make rlogin to close the connection.  The shells will
all exit in response to that.  (And you can do the same with ssh,
which you should be using instead of rlogin.)

-- 
Mike Stroyan
stroyan@gmail.com

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> What about in your login (.bash_profile, etc) exporting a 
> variable, say 
> ROOT_PID=$$ and having a command/function/alias 'kill -s SIGHUP 
> $ROOT_PID'? This is equivalent to killing the rlogin connection, but 
> should clean up nicely if all you have are shells.

Excellent idea! Thank you for this suggestion.

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> >    rlogin foobar
> >    DO SOME STUFF
> >    cleartool setview myview # this creates a subshell
> >    DO MORE STUFF
> >    cleartool setview yourview # now I'm two subshells deep
> >    DO STILL MORE STUFF
> >    # Now I want to exit
> >    exit
> >    exit
> >    logout
> >
> > I would like to have a (interactive) command which does the 
> final two
> > exits plus
> > a logout for me.
> 
> exec cleartool ....

I gave "cleartool" just as an example. The point is not that I do not
want
the subshells to NOT be created. In contrary, I *want* to have the
subshells
(and they are not always created by setting a view, but sometimes simply
by invoking "bash" or "zsh" respectively), because I often want to make
changes in the environment, do something, and then undo the changes,
i.e.
go back to the previous state of the environment. But there *are* quite
often
cases that I am deep in a series of interactive subshells, and decide I
do not want to back up one or two levels, but leave all of them and
logout.

So your solution doesn't solve the original problem either....

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> > I can't use traps here, because I know only at "exit time", whether
> > I want to logout completely, or just go up one level.
> 
> $ call_and_exit() { "$@"; if test $? -eq 42; then exit; fi; }
> $ call_and_exit cleartool ...
> $ exit 42

This looks clever. Maybe one should use "exit 42" too in the definition
of call_and_exit
to propagate the exit up, but basically a nice idea. Maybe only
disadvantage that I have
to think before when calling the subshell (either by calling it via
call_and_exit, or
by setting up suitable aliases for cleartool, bash, zsh etc., to do this
automatically)
- I had hoped I cut do this with an intelligent alias which gets me out
of any deep
nesting of subshells without having done any preparation work before.
But your solution
is at least cleaner than the brute-force way of finding the login shell
via ps, and
then killing it.

Will give your idea a thought. Thanks a lot.

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com

RE: logout from interactive subshell

[Com MN PG P E B Consultant 3]

> >    (1) rlogin to a foreign host
> >    (2) Invoke a subshell (for example because I'm setting a 
> Clearcase
> > View)
> >    (3) Logout from the host
> > 
> > Step (3) needs two steps: First I have to type 'exit' to leave the
> > subshell, and then either 'exit' or 'logout' to leave the 
> login shell.
> 
> On step (2) you use 
> 
> exec bash
> 
> instead of just bash.

This does not work in the general case since I don't know at the time of
invoking
bash, whether I will eventually just go back one level or logout
completely. 
Imagine the following situation:

  rlogin foo
  VAR=val1
  exec bash
  VAR=val2

Now if at this point I would decide to not logout, but just go up one
level (in order
to have the old value of VAR restored), there is no way to do it -
typing exit would
log me out *unconditionally*.

Ronald
-- 
Ronald Fischer (phone +49-89-63676431)
mailto:mn-pg-p-e-b-consultant-3.com@siemens.com