🚀 go-pugleaf

In <stephenkDp17xt.Boo@netcom.com> stephenk@netcom.com (Stephen Knilans) writes:

>In article <danpop.828050308@rscernix> danpop@mail.cern.ch (Dan Pop) writes:
>>In <stephenkDowqB9.F4E@netcom.com> stephenk@netcom.com (Stephen Knilans) writes:
>>
>>>In article <danpop.827809042@rscernix> danpop@mail.cern.ch (Dan Pop) writes:
>>>>In <4j6lv1$k3r@news.mpd.tandem.com> Joseph Crowe <jcrowe> writes:
>>>>
>>>>>danpop@mail.cern.ch (Dan Pop) wrote:
>>>>>>Can you use a Unix system without a shell?  Try to remove all the shells
>>>>>>from your Unix system and see what you get :-)
>>>>>
>>>>>   Absolutely.  You could have a user login on a *NIX system and in the
>>>>>/etc/passwd entry for that user, have whatever binary you wish to provide the
>>>>>user interface.  That could include a totally graphical interface if one so
>>>>>desired.
>>>>
>>>>Your Unix system won't even boot without a shell!  Just remove all the
>>>>shells, as I suggested and see if you can use that box, no matter what
>>>>you put in /etc/passwd as the user login shell.
>>>
>>>You have NO idea what you are talking about!
>>
>>If this is true, then remove /bin/sh and try to reboot your Unix system.
>>It's as simple as this.  You'll see who is the guy who has NO idea what
>>he is talking about.
>
>I DID!

And what happened?

>>>>The shells (or at least /bin/sh) are part of the design of a Unix system.
>>>>Library calls like system() and popen() or system components like cron
>>>>rely on the existence of /bin/sh and simply don't work without it.
>>>
>>>cron uses a shell to SIMPLIFY things!
>>
>>It uses a shell to execute the shell commands scheduled in the crontab
>>file. 
>>
>>>Don't you need to have lotus 1-2-3 to
>>>have full 1-2-3 functionality?  HUH??????
>
>If you delete lotus 1-2-3, you can't use that program!  ERGO, if you delete the
>shell, you can't use the shell.  SIMPLE!

If you delete /bin/sh you can't use the system at all, because this
program is a critical OS component.  SIMPLE, indeed.

>>I fail to see how your "point" relates to your claim than /bin/sh is not
>>part of Unix.
>
>I said it wasn't necessary!
>>
>>>system means "send command to SHELL"!!!!!!!
>>>popen means "open a SHELL and use a pipe for terminal I/O"!!!!!!!
>>>cron means "send a command to the SHELL at a particular time"
>>>
>>>NOW HOW do you send a command to a shell without having the shell, HUH?
>>
>>This was precisely my point, which shows that I knew perfectly well what
>>I was talking about.  system(), popen() and cron are parts of the Unix
>>operating system.  Remove them and you have something which isn't Unix
>>any longer.
>
>WRONG!  

Shouting is not a good substitute for a proof.
>>>
>>>>>>BTW, you found no contradiction:  Will Packard is perfectly right, Unix
>>>>>>is not one or more shells, for the simple reason that the shells are a
>>>>>>component of the Unix system.  The other components are the kernel and
>>>>>>the system utilities.  All these components define a Unix system.
>>>>>
>>>>>   Shells in *NIX are applications, pure and simple.  
>>>>
>>>>True, but irrelevant.  Everything in Unix is an application.  Some of them,
>>>>(e.g. /bin/sh, getty, login, init, ifconfig) are critical components of 
>>>>the operating system.
>>>
>>>I don't believe I have EVER used sh here!  
>>
>>You mean, not explicitly.  Enable accounting on your Unix system and 
>>have a look at how many sh processes are being run, behind your back.
>
>I HAVE looked!  Many programs *I* write DO run a SHELL, albeit NOT SH.  KERMIT,
>for example does NOT, even though it forks itself off.  OTHERs that execute
>programs don't.  WHY??????  Becuase they EXEC, and DON'T call system.

Completely irrelevant.  Another program, written by someone else, will
stop working, despite being a correct Unix application.  Hence, your
Unix system will be broken.  cron will also stop working, and it is
another standard Unix component.

>>>I am planning on getting rid of getty, and have in the past!  
>>
>>So what?  If you don't use it, does it mean that it isn't part of Unix?
>
>ACTUALLY, unix itself is a KERNEL.

By whose definition???

>It merely controls tasks.  It isn't 
>multiuser, can't take directories, etc....  Auxillary programs, that have
>been adopted as standards, and thus CONSIDERED, part of UNIX make it 
>multiuser, etc...

Plain bullshit.  Without multiuser support in the kernel, your "auxiliary
programs" would never make Unix a multiuser system.
>>
>>>Let me set you straight, ok???  UNIX is TRULY only a multitasking system which
>>>has all things running at a high level.  init manages tasks, or which one is
>>>getty.  getty simply waits for a signal to start login.  login starts the
>>>shell(which could be ANY program)!  
>>>
>>>ifconfig?  That is simply for NETWORKS!  Are you telling me the macintosh has
>>>NO ability to configure networks?
>>
>>I'm telling you that without these components, which are all "Unix 
>>applications, pure and simple" your Unix system won't work at all.  It's
>>as simple as this.  You can definitely design an OS which will work 
>>without them, but that system won't be Unix any longer.  Got it?
>
>MANY unix applications DON'T use these!  BBSs VCL, for example, can REPLACE the
>shell, and doesn't need any other!  cron is used only if you want.  Some NEVER
>use ifconfig(I didn't for over a year on this system, ,still haven't after 3
>years at work)!

So what?  There are plenty of Unix applications that rely on those
components to work as advertized and which would break themselves if 
those basic Unix components stop working.  What's so difficult to
understand?  Who cares that my "hello, world" program will continue to
work?
>>
>>>>Plain bullshit.  Remove all the system utilities from /bin /usr/bin /sbin
>>>>/usr/sbin, etc and see what you can do on that Unix system.  After all,
>>>>you still have the kernel and the libraries.
>>>
>>>Try removing all the system files on the MACINTOSH, and see how far you get!
>>
>>We were talking about "applications, pure and simple", not about system
>>files.  I didn't ask you to remove any of the Unix configuration files,
>>only "applications, pure and simple", like /bin/sh, right?
>
>It is those unix configuration files that dictate what applications it will 
>need,  and you KNOW it.  I HAVE had to run without nearly everything.  I
>made a minimal boot disk(which incidently had NO sh shell!), 

Sorry, the idea was to have "no shell", not "no sh shell".  Can you spot
the difference?

>and HAVE done
>what you requested.  It actually runs BETTER!  

You must be using a very personal definition of "BETTER" :-)

>Of course, I want to have more 
>flexibility generally.

And you want to have something that could be called Unix and used as such,
not something that after booting doesn't give you the full functionality
of the OS, because lots of standard components don't work any longer.

Dan
--
Dan Pop
CERN, CN Division
Email: danpop@mail.cern.ch 
Mail:  CERN - PPE, Bat. 31 R-004, CH-1211 Geneve 23, Switzerland